2013-14 VEX Toss Up Engineering Notebook

Engineering Notebook VEX Team 8756 McCallum High School 2013‐14

Date: 09‐05‐2013 Start Time: 4:15 End Time: 5:30

Recorded By: Dexter Snacks: Chips/Fruit Leather Page:

TASKS REFLECTIONS

Figure out which tournaments we will be participating in this season. Since there are quite a lot this year that are happening in Texas, we have a lot of options and will probably be attending a decent amount.

We have decided on specific competitions to attend in the Austin area, and one in Houston, there are some other possibilities in the Houston, Dallas, and Austin areas. There is a larger competition that is qualify‐only later in February, so if we qualify, we will attend. The overall goal of course is getting to worlds.

Consider ideas for recruiting new team members, both upper and lower classmen. Lower classmen are preferred since all of the current members are seniors.

So far Dexter has gotten one possible new member who can attend some of the meetings. In the long run, we want new members who are in lower grade levels so that there is still a team next year when the current seniors leave.

Tournament Possibilities:

Scrimmages before any official competition

Houston Regional Competition

Austin VEX Competition

Killeen Regional Competition

Possible: South Texas Regional Competition Recruiting Ideas:

Sponsor will talk to underclassmen in her various CAD and engineering classes

Convince friends to create a B‐Team

Signage in the halls

Morning announcements


Date: 9/10/2013 Start Time: 4:15 End Time: 5:30

Recorded By: Dexter Snacks: Chips Page:

TASKS REFLECTIONS

Brief the new recruits for the B‐team on the goings‐on and rules of Vex in general and the new competition in specific

The new team has begun assembling the VEX proto‐bot to teach them the ways of robot building. So far they seem pretty interested in the prospect of making the robot and competing in the regional Austin tournament.

Remove the linear multistage slide lift (1103‐style) since it was too big for the robot and not very convenient for our purposes

Now we need to come up with an idea for the intake and a method for hanging the robot, hopefully high hanging. We’ll be making plans for the intake between this and the next meeting.

Oversee the new team, make sure they are going strong, and working diligently, meanwhile discussing intake ideas for our robot.

They are working fine, and our discussions.. well they devolved a bit into discussing school, and other non‐VEXian topics.

Remove the plate that the brain sits on so we can replace the metal with aluminum and move the brain to a different location

The new location for the brain will help save space for things such as the intake and hanging mechanism.



Recorded By: Dexter Snacks: Girl Scout Cookies Page:

TASKS REFLECTIONS

Discuss intake/linkage designs for the robot We have decided to have an “NZ” style intake, with horizontal rollers on the sides of the intake. We had an idea to move the basket separately, but we will make the rollers go along with the robot.

Discuss food We need food for every robotics meeting, hungry kids=no progress

Remount the brain towards the back of the robot, for looks and ease of access.

This will be helpful for making the brain easy to access, and also make more room for linkage/intake/and more.



Recorded By: Dexter Snacks: none Page:

TASKS REFLECTIONS

Brief a new senior member of the robotics team on the goings‐on of our robot and the contest. He’ll be on our team since he is a senior, and wouldn’t be much use on the freshman team.

Dexter and Jake will begin working on an intake soon, and JT and Aidan will work on a lift method.

Remount the brain It works now, and we can put batteries in the slot we made, which is useful.

Discuss intake/lift methods Basically our best idea is to create a horizontal roller mechanism, but we’re still not sure about the basket part. The lift is going to have to reach about 40 inches, in order to hang.



Recorded By: Dexter Snacks: Pirate’s Booty Page:

TASKS REFLECTIONS

Work on the intake, strengthening it in order to attach the motors and the roller that will actually intake the buckyballs

Since the intake basket was initially made out of 1x25’s, it’s very difficult to strengthen it, since we basically have to take it apart and rethink it completely.

Work on a linkage design that will go in between the treads of our robot and also stay under the 12” height limit we have set for ourselves. We will not be using any sort of reverse linkage and currently are leaning on the idea of a 6‐bar.

After Aidan stared at metal long enough, he came up with a standard 6‐bar linkage design we can use that stays under the 12” height limitation if we cut the extra ends off some of the pieces, and also reaches over 40” into the air, perfect for high hanging.

Sort screws, metal, and all of the loose junk on our worktable.

This is just an ongoing process that will probably never end until we spend multiple hours just organizing, sorting, and finally everything will be clean.



Recorded By: Dexter Snacks: Fruit snacks‐Chips Page:

TASKS REFLECTIONS

Work on an intake that focuses simply on collecting the bucky‐balls.

This has gone smoothly, we have decided, finally, to use a horizontal roller with a chain attached to a powered gear in the center of the roller.

Create an 8‐bar linkage that stays under the 12” barrier we have set for ourselves when fully retracted and then extends at least 35”‐38” in height to reach the hanging bar.

It looks good; there currently aren’t any visible issues with it. But the one thing we don’t know for sure is how stable it will be.

Cut aluminum c‐channels on the linkage to fit under the height limit, as the pieces that need to be cut are excess.

This worked, we needed a jigsaw, but Aidan’s dad has one, so we were able to easily cut through the aluminum like butter.

Replace some steel parts on the drive base with pieces of aluminum to lighten the load on the back of the robot.

The aluminum has helped make the robot lighter overall, and has also improved the center of gravity extremely, now there isn’t as much of a back tipping issue.

Build a gearbox for the linkage. Gearbox looks solid, it was built so there are no axles with unsupported areas, so there won’t be an axle twisting issue. But stripping might turn out to be a problem.

Build a motor mount and mount the motors for the intake mechanism.

The motors don’t seem super stabilized, but since all they are doing is powering the rotating ball intake, it shouldn’t be that big of an issue.

The roller is on a swinging arm that is stopped so it’s high enough at the end to fit a ball




Retracted (12 inches tall)

Extended (41 inches tall)




Gearbox (top); All of the –current‐ disassembled parts (bottom)



Recorded By: Dexter Snacks: Cheese squared Page:

TASKS REFLECTIONS

Attach the intake to the arm This went well, we don’t have the intake at the highest point on the arm since it’s not necessary, so there is a little horn‐looking peak on our arm.

Wire up the motors on the robot Went slow at first since some of the motor controllers were hidden behind motors which had to be unscrewed to get plugged in, but in the end we got everything plugged in very easily.

Begin programming the robot Very easy since in a programming sense, our robot is the same as our Sack Attack Robot, so the only things that need to change are the motor numbers.

Figure out where we need to put a hook on the top of our arm for robot high hanging purposes.

Using some trigonometry we were able to easily figure out how our robot fits in the corner of the field and decide on a position for our hook.



Recorded By: Dexter Snacks: Pretzels Page:

TASKS REFLECTIONS

Add a program to the tank tread robot and test the results.

After extensive testing we realized several problems: 1. Couldn’t get over bump 2. Massive friction 3. Because of the friction, our motors

experienced massive resistance making them overheat immediately.

4. Really bad derailing on the bottom 5. Tread slips off (clicks) over the

powered sprocket

Completely remove all of the tank tread mechanisms, except for the motors themselves as they are in a good, solid spot.

This involved, first and foremost, unscrewing and removing all of the rubber band tensioned tread suspension. Then, removing all of the miscellaneous odds and ends that were involved with attaching the tread to the robot.

Come up with a new idea for our drive train. We have decided to go for a localized motor design, using the top wide c‐channel as the supports for each motor. There will be a total of 6 wheels, each with one motor to prevent friction, and to get our robot over the bump.

Begin the assembly of the new drive train. So far, no progress has been made on the drive, but we should have it done by Thursday of next week, the day when we begin packing for Houston.

Critical Deadline: October 24, 2013 – Need to have robot finished




Completely disassembled robot


Date: 10/19/2013 Start Time: 9:00 a.m End Time: 4:15 p.m

Recorded By: Dexter Snacks: Whataburger Lunch Page:

TASKS REFLECTIONS

Create a wheeled drive train for our robot.

Six wheels powered by six motors (1 motor per wheel)

Decide on a method for mounting the motors (direct drive vs. a motor block at the back end of the robot)

Figure out how to attach each wheel to the motors

We decided to use the largest wheels provided by VEX, they are just standard wheels, not omni or mecanum. We decided to go for a motor mounting solution with 2 groups of 3 motors on the back right and left sides of the robot. We attached the motors like so:

1 small sprocket chained to another on the inner‐outside edge of the wheel base.

The axle attached to the chained sprocket powers a long length of high strength chain that winds around the wheel base, powering each wheel.

The drawback to having all of the motors positioned at the back of the robot is that it could create a backwards tipping problem like we had before, but so far it seems like our robot has a sensible center of gravity.

Prevent the high strength chain from slipping off of the sprockets by using a tensioner.

This was most important for the chain connecting the motor block to the powered sprocket, and all we really had to do was slide in another small sprocket so it spreads out the chain very slightly, no rubber band tensioning mechanisms necessary.

Build the framework for the “tower” of our robot, as well as a mounting solution for the brain, power expander, and wires. For the brain and power expander, we are just hanging it off the back plate of the robot with 1x25’s. For the rest of the wiring (motor controllers, sensors, etc..) we are tucking all of the wiring in the space between the two 5x25 c‐channels.

Our tower is not even a normal “tower”, there are really only two 5x10 c‐channels that make up the entirety of the tower, this is where our arm’s gearbox will be exclusively, making it quite difficult to compact it enough. The wiring will be pretty straightforward and tidy, but possibly difficult to access.

Gearing




One side of the wheel base

The wheel base motor block/gearbox




The completed (and new) wheel base

The new wheel base and “tower” with the arm in place (not attached)




TASKS REFLECTIONS

Design and build a gearbox for the arm. Our gearbox is very condensed, using high strength gears, no chain, and one motor per arm.

This gearbox looks like it will work very well, there are not that many gears, and the lack of chain makes it very rigid. On the other hand, there are a couple very small spaces between some of the gears, so there’s the possibility for the gears to touch during a heated match in competition.

Wire the robot – hook up all of the drive motors and arm motors to motor controllers and plug 2 drive motors from each side of the robot into the power expander.

This took a lot of 5 cent zip ties to complete, which is unfortunate both financially and in terms of usability, because a lot of the wires are completely wrenched down on the back 5x25’s, making them both hard to reach and hard to work with.

Begin thinking about adding the hook This didn’t go very far…

Organize a box of parts that can be taken to a competition and has only the necessary parts for a competition, that way we don’t need to bring as much, and only have the absolutely necessary parts for our robot.

Aidan seemed to be doing well with this task, and found a lot of low‐strength gears which were consequently unsorted into a plastic bag.

New Gearbox – 15:1 ratio Robot Wiring



Recorded By: Dexter Snacks: Cookies Page:

TASKS REFLECTIONS

Finalize the wiring on the robot; basically all that needs to be done today is connect the rest of the wires to the cortex.

This went really fast, there wasn’t much that needed to be completed for the wiring. Then Dexter made a diagram for Aidan depicting all of the motor numbers and the ports where they are plugged into on the cortex.

Remove the middle wheel on each side of the robot and reconfigure the chain a little bit so there was no stopping between the front and back wheels.

This will actually help us go over the bump much easier, because the 5x35 c‐channel is actually about 2.5 inches above the ground, so after the leading wheel clears the bump, our robot can straddle the bump. One issue that might come up is that we have a long stretch of completely exposed high strength chain which may get caught up in another robot’s arm or other mechanism which would be very bad.

Begin programming the robot. Going slowly, Dexter’s diagram for the motors and ports seems to be mildly useful, but the way he wired the robot is pretty confusing since the ports and motor numbers don’t line up.

Now there is simply a chain running from the powered wheel to the front



Recorded By: Dexter Snacks: Fruit leather Page:

TASKS REFLECTIONS

Replace the two arm motors and one of the driver motors, its internal gears were completely stripped out, then rewire those three motors.

This wasn’t too hard of a task even though all of the wires are zip tied down to the robot, and it is very helpful since working motors that aren’t stripped help things.

Attach potentiometers to the arm axles and possibly optical shaft encoders to the drive, but we aren’t sure about those.

This will help us install the arm‐stabilization program to the robot so our arm won’t go below the wheel base (making it pop up) and keep it from dropping on its own.

Add the basic drive and lift program to our robot and test for any possibly friction points.

So far it seems like this new drive will serve us very well, there isn’t much friction in the sprockets and the wheels can very easily go over the bump. The arm motors, unfortunately, are not strong enough to lift our robot and hang.

Dexter will work on finalizing the engineering notebook, polishing past pages he’s done.

This went well; the only thing that really needed changing was the times on each page, and adding in some photos for the more recent pages.


Date:10/26/2013 Start Time: 7:30a.m End Time: 5:00p.m

Recorded By: Dexter Snacks: BBQ Sandwich Page:

TASKS REFLECTIONS

Compete in the Houston Regional robotics competition – we had 5 matches in total, we won the first 2 matches and lost the last 2, we had no ally in our last match so it was a pretty easy win for the other alliance.

Our robot was semi‐decent overall, pretty much all of the elements of our robot will be changed – wheel base, motor mounting, wheel type, intake type, and more, we will be keeping Aidan’s linkage since it is probably the most unique and strong linkage we’ve built in a long time.

Fix ongoing problems that occurred during matches and during practice. One of the major problems that kept popping up was that the chain connecting the 3 motors to the wheel chain would break over and over again. Another issue that came up was that our intake mechanism would drag along the ground, so we added a simple float mechanism (standoff) to get it off the ground a little. The last major problem, which ultimately led to the demise of our robot, was that our wheels were incredibly grippy making it nearly impossible for our robot to turn in place. During one of our driver skills challenges our robot actually sheared off screws on the tower due to the immense torque being applied to the robot because of the wheel grip.

On our next robot we will resolve any chain problems by using gears wherever possible and likely by using direct drive on our wheel base – motors on the inside of the chassis, and wheels on the inside. We have decided that we will probably be using omni wheels for our drive base because they allow our robot to turn in place very easily. We will stick with a 4‐wheel drive since 6 wheels aren’t really necessary and would require extra power that we have decided to devote to the lift (4 motor lift geared down at 15:1). Our robot’s construction was also not particularly splendid; we used way too many standoffs in very important places on our robot which we will be changing on future robots of ours.

We weren’t picked for finals, but we still watched all of the finals matches for fun and to see if won the Excellence award, which we didn’t.

We were actually happy we didn’t get picked for finals, because our robot would not make our alliance member very happy, finals requires a robot with longevity, something our robot clearly, and unfortunately lacked.


Date:10/26/2013 Start Time: 7:30a.m End Time: 5:00p.m

Recorded By: Dexter Snacks: BBQ Sandwich Page:



Recorded By: Dexter Snacks: Cheese Squared Page:

TASKS REFLECTIONS

Discuss new possible robot designs and solutions to problems that arose during the Houston regional competition.

Problems with the old robot:

Wheels are too grippy for turning and maneuverability.

Chain connecting the drive motors to the wheels keeps breaking.

The 6‐motor drive isn’t really necessary when it could be dedicated to the lift.

Our drive base is much longer than other robot’s, so in order to fit in with the crowd and in order to get over the bump easier we’ll use a shorter base.

Our top‐roller intake design proved to be quite ineffective compared to the side rollers used by other teams.

We have decided to fix the problems that have arisen by using a short (20‐25 long) drive base using only 4 wheels and powered directly (one motor per wheel) so we have 2 extras for the lift. 4 motors on the drive is plenty for 1:1 and 4 motors on the lift using the same gear ratio (15:1) will enable us to lift and score extra points. In addition we will reduce chain usage and standoff usage to strengthen the robot and prevent breakage.

Doug will begin disassembling our robot to give us maximum time before the Austin Regional Competition to design and build the robot.

Doug’s disassembly proved to be immensely useful, because we were able to finalize our ideas and divide up labor for the next iteration of our robot. Plus, as a bonus, Doug organized all of the parts as he disassembled something none of us would have done.

MECANUM DRIVE We will be using a mecanum drive in all of its strafing glory, because while an omni drive would allow us to turn easily, we could very easily be pushed sideways across the field which would be very bad for us. Strafing will also allow us to accomplish some desired tasks.



Recorded By: Dexter Snacks: Cheese Squared Page:



Recorded By: Dexter Snacks: cookies Page:

TASKS REFLECTIONS

Aidan made the decision to use direct motor‐> axle‐>wheel with the mecanums being flanked by aluminum c‐channel that are both 25‐long, so our wheel base has changed in three ways – new wheels, new size, new motor mounting, and this time with 100% less chain!!!

The shorter wheel base means the wheels have to stick out a little past the edges of the c‐channel which means they will undoubtedly hit the bump first, therefore less momentum will be lost, second the smaller drive means the wheels are closer together, meaning it’s harder for our robot to get caught on the bump. Lastly, and most obvious, is that the mecanum drive will prove to be quite useful, or at least more so than sack attack, because there is a lot more maneuvering that can be done when avoiding or picking up balls.

J.T began working on an intake design, but didn’t get very far since intakes are one of the weirder, more obscure things to design.

J.T has some interesting ideas for the intake that may or may not prove to be useful, or even buildable, it’s difficult for him because we have a very tight, but vague size restraint – it must fit between the lift arms, but we’re currently not even sure how wide that is.

Misc tasks: Dexter cut 3 full length aluminum c‐channels down to 25 units long, Aidan helped Doug teach the M‐team some basic programming to get their robot up and running, and Dexter copied what Aidan had done for one side of the drive.

Cutting the aluminum with a jigsaw is easy, M‐team seems to be doing good work, they already have their own tank drive nearly finished and programmed, now they will have to begin thinking about lifts, and by the sounds of them talking about linkage concepts, they are well on their way.




TASKS REFLECTIONS

JT worked on the intake some more, deciding it would be the best idea to use the largest sprocket for the intaking part and attaching the motor to the same side of the c‐channel that the roller is on, just spacing them enough so none of the flaps get caught on the powered chain or the motor.

This intake design should work very well, or at least from what we’ve seen at competition it will work very well, we will have chain with flaps attached for intaking the bucky balls and on the top of the axle, a smaller intake mechanism for the big balls.

Aidan had to rethink the wheel mounting solution we were using, because the old one was scaring us with its insecurity and plastic qualities. The new one utilizes cut 1x25 pieces, bearing blocks, and standoffs and seems pretty secure for being relatively dumb.

The new mounting solution is more effective than the plastic pieces we were using before, and although its construction is dubious, it is surprisingly sturdy. Unfortunately, we don’t have a good place for the front motors currently which presents a problem for the arm and intake.

Other tasks: the tower was slightly modified in order to get it more secure and more efficient, Aidan and Dexter spent a good deal of the time thinking about a new method for mounting the front motors so it’s out of the way of the intake mechanism.

The motor mounting problem is going to be the biggest issue when moving forward with our robot, so before we attach the tower we are going to have to slowly move through the process of making a new mounting system for the front, most likely attaching the motor to the inside of the drive base and then connecting that to the wheel via chain that runs along the outer‐inner edge of the wheel base.

The current selection of mechanisms of our robot




A close‐up of the current wheel mounting mechanism


Date: 11/1 – 11/3 Start Time: 12:00 End Time: 5:30

Recorded By: Dexter Snacks: CHZ2 Page:

TASKS REFLECTIONS

Rethink the drive base power system – this involved moving the motors inwards, so they are both right next to each other and connected via chain to the mecanum wheels. The motors are also now located above the c‐channel that attaches the wheels.

This is much better solution to what we had, because now the front motor is out of the way and still just as easy to remove as it was when we had direct motor to wheel power with no chain involved. We tested the drive and it seems to be working fairly flawlessly, if we had the robot fully assembled and the weight properly balanced, we think it will work perfectly fine.

`Think up a solution for the arm, since the wheels require a wider drive base, there is less room between the two sides of the drive base to have an intake, but since we want to intake large balls, we have to have a wide enough intake for them, so in the end our arm has to clear the wheels but also start at a lower height.

The lowered starting height and need to clear our drive base has driven us to make a 10‐bar linkage, which we have officially dubbed ham‐bone. Aidan will begin working on the linkage as soon as we have the 15‐long c‐channel pieces required for it.

Create the gearbox for the arm and attach two motors per side to provide sufficient power for lifting.

This required a little bit of interesting gear‐work, but not too much, it was basically getting a 15:1 gear ratio and have two motors powering each arm.

Make minor modifications to the intake mechanism including perfecting some of the attachment methods, tightening screws, and compressing the whole thing into a 10 unit long mechanism that is attached onto a 15‐long c‐channel.

Having the mechanism about 5 units shorter than the c‐channel it is attached to allows us some free space for creating a mechanism that allows the rollers to either fold upwards or inwards, something required for our robot to be in dimension.

Make the whole chassis of the robot sturdier – adding cross braces and eliminating standoffs wherever possible.

This helps our robot during competition because the screws won’t loosen as much, and none of the mechanisms we have built have a chance of becoming detached, something that happened at Houston. By having a more rigid robot we ensure that if our robot makes it to finals, we will be able to endure the stress that finals puts on robots.




Front of the robot with new drive motor mounts and arms motors attached

Close up of the drive motor mechanism (motor to sprocket to chain to sprocket to wheel)




Close up of the arm gearbox with the two motors visible to the left

Intake mechanism – bucky roller underneath, large ball roller above (not attached currently)



Recorded By: Dexter Snacks: CHZ2 and Candy Corn Page:

TASKS REFLECTIONS

Now that we got a shipment of 35‐long aluminum c‐channel we can begin constructing our linkage arm. Aidan began assembling it without any prior planning and got a pretty efficient 8‐bar linkage that reaches over the wheels and hits the ground at the end.

We are all very glad that the linkage didn’t turn out to be very bad, an 8‐bar is completely tolerable, although there is an issue of it not reaching 40 inches, currently it only reaches 32 inches high so hanging might be an issue if we don’t figure something out before the competition this Saturday.

We tested the gearbox for the arm, currently a 15:1 powered by two motors on each arm, and we were able to begin warping the aluminum chassis before the arm would budge when we held it down – this was only with a stubby little arm section that would start the linkage, so it’ll become more difficult for the robot once we have the full arm on.

The gearing and motor system we have working currently will be extremely effective for lifting, plus we have taken steps to get our robot as light as possible – almost no 5 wide c‐channel, and a very small number of large pieces, and no steel parts, all of this makes for a much lighter robot which will help for speed and ease of lifting.

Configure the motors for a fully functioning mecanum drive – involved Aidan writing a simple mecanum program then flipping a couple motors to perfect the system.

The mecanum drive, after testing it, seems a little slow, for sure slower than the 5.5” wheel base we had, but that just comes with the smaller wheel size, but seeing the robot strafe for the first time made us all realize that a mecanum drive is a very good idea.

Linkage in progress – only one more bar to go until it hits the ground!



Recorded By: Dexter Snacks: 1 Butterfinger/person Page:

TASKS REFLECTIONS

Quickly alter the linkage a little bit to ensure that it reaches the ground to an ample degree as well as clears the drive base easily. Aidan took a little longer than expected on this, so it slowed down progress on the intake mechanism a little.

The final linkage will reach about 35 inches, so we need the hook to reach a little higher than the top of the arm – we will be lifting with the end of the arm, not the top of the intake mechanism like we saw some teams doing. Plus the linkage looks a little crazy – a lot of bars in a small amount of space.

Begin thinking about an idea for mounting the intake rollers onto a basket sort of thing to hold up to 3 bucky balls.

The intake rollers will flip down at the beginning of the match, so there has to be enough room for them to do this (no obstructions for the flaps) and they have to connect to the actual mechanism we will use to contain the bucky balls.

Mount the brain and power expander Our brain will be mounted sideways towards the back of our robot, a suggestion from Anderson High School’s robotics team (2158m). We also got a new power expander since our old one had a faulty battery wire and would get unpowered during matches and while driving.

Mount the batteries The batteries are in the middle of the robot, to balance it out – the batteries are primarily what we will use to balance the robot for our mecanum drive, but currently they are just secured on small plates and strapped in with the battery zip‐ties.

Competition is this Saturday, so we have very little time for finishing our robot and finally

testing it on a field – which we have acquired. This Saturday’s competition is at Anderson High School, very near to McCallum which is fortunate because we won’t have to drive far to get there, and no hotels necessary. Luckily all we have to do in order to finish is build the intake

basket which will probably happen tomorrow and testing on Friday.



Recorded By: Dexter Snacks: 1 Butterfinger/person Page:

Battery, cortex, and power expander mounting Display of the up/down linkage positions


Date: 11/9/13 Start Time: 2:45pm(Fri) End Time: 12:00am(Sat)

Recorded By: Dexter Snacks: Pizza, Torchy’s Tacos Page:

TASKS REFLECTIONS

Friday – work on the robot, adding finishing touches to the drive base, linkage, and any other various mechanisms that need tweaking.

Most of the work that wasn’t related to the intake was tightening screws or adding little pieces of metal to certain parts to strengthen the robot or make it more usable.

Friday – Change the intake mechanism so it flips down after starting within the 18” length requirement and hinges outwards so it envelopes the bucky balls. This took an incredibly long time to assemble due to its increased complexity and strange attachment location on the robot’s linkage and intake trough.

The ability for our intake to hinge in and out will be very useful because it both helps keep the bucky balls in the basket we made, and also seems to work better than a normal intake mechanism because of its dual intaking action – the rollers and the pulling in of the entire rotating mechanism itself. Unfortunately we didn’t really design our arm and intake with this plan in mind so it was mounted completely too insecurely and needs to be thought about more for our next robot redesign.

Friday – we had worked late into the night at Aidan’s house where a field was setup and we worked on finishing the actual physical robot, Aidan put a program on the robot to test the mecanum drive, the arm, and the two intake mechanisms. Something happened with the intake mechanisms that made it so they spun weird, and Aidan was able to pinpoint the area in the code that made that happen. He also made a very slight outline for an autonomous we could use to knock the two big balls on the 12” barrier over.

The outline for the autonomous helped enormously for getting a finalized intake working for the competition, an autonomous that would inevitably score a total of 10 points for our alliance and generally help us win the autonomous bonus on multiple different occasions. In addition, the general programming of our robot’s driver control mode went smoothly, Aidan is very used to programming now, so he’s able to whip up something like a mecanum code very easily, plus the motors were logically laid out this time making programming a whole lot easier.

Saturday – compete in qualifications for the Austin VEX Competition, we had a total of 5 matches with alliance members varying from a couple push‐bots to an ally like the world‐renowned Discobots, in fact we were able to make a little friendship with Discobots that would help us greatly in finals, because during alliance selection we were in 15th place and when they got picked by 1366, they suggested our team as

Overall, one of the biggest things we’ve taken away from this competition is our team’s friendship with the Discobots which will help us greatly in future competitions such as San Antonio and the South Texas Regional which we have now qualified for. We played good matches with Disco, them being the scoring team and us being great defenders, helping fend off teams like 4252a and 2158m, both teams that


Date: 11/9/13 Start Time: 2:45pm(Fri) End Time: 12:00am(Sat)

Recorded By: Dexter Snacks: Pizza, Torchy’s Tacos Page:

a second pick and we did, in fact, get picked by 1366 to be allied with Discobots in the finals. We advanced through the quarterfinals and semifinals pretty easily and once we reached the finals we found ourselves against 9090a, 9090c, and another team, but 9090 or T.Vex was the real competition on their alliance. The first match our robot’s arm got caught on the arm float we had constructed that day upsetting us greatly, then the next two matches which our alliance won was played by 1366 and 2587z. They were both very close and T.Vex put up a huge competition to us, leaving us with a 1‐point advantage in the final match. In the end we won the competition on the backs of the far superior team: 2587z.

performed incredibly well at the World competition last year during Sack Attack. Another very positive benefit of this competition is the improvement of Dexter’s driving, he went from barely being able to navigate the field at Conroe to being able to score the maximum number of bucky balls in one swift go, something not many other robots and drivers can do so soon. We have also walked away with some plans for our next robot and nearly a month to perfect it which will be very good since then we’ll have time to build, test, and refine, something we have only been able to do on a very small scale at competition.

We also had the pleasure of receiving the Design award at the Austin VEX Competition, another South Texas Regional qualifying award.

Dexter was extremely pleased that the team received this award, because he has been working extremely hard on the engineering notebook, reflecting on nearly anything he can, and putting in pictures wherever possible, except this page, funny enough since it’s about the competition where we won the award for our notebook.




Robot pieces

TASKS REFLECTIONS

Disassemble our old, award winning robot from the Austin competition. This didn’t involve much time or effort, because there really wasn’t much to disassemble, so we mostly conversed at Aidan’s house while disassembling the robot.

When we finished disassembling the robot we realized just how many bearing blocks and half‐inch screws we ended up using on the robot, quite amazing really, but weirdly we had an incredibly small amount of metal that we actually used on the robot. By disassembling the robot early, we were able to begin working on the robot itself sooner.

Discuss ideas for the robot; 1. Omni‐wheel, 6 motor drive to help

with the robot’s speed, since we could possibly gear the robot up.

2. 7:1 gear ratio on the arm for faster lifting, unfortunately this makes it harder for us to hang, even when we couldn’t before making this change.

3. Possible piston‐assisted lift, but we just saw Pastoral Invasion using a 7:1 gear ratio and 4 motors on the arm lifting their robot, so we might transition to something like that since it would be much simpler.

Omni wheels will allow us to use tank drive for more precise movement of the robot, especially when scoring and maneuvering around obstacles like other robots and big balls. In addition, the omni‐wheels will help our robot go a little bit faster which is something we seemed to be lacking in our previous robot. On the note of faster movement, a 7:1 lift is very necessary for lifting, because it will allow our robot to score quickly and not make us wait for the arm to fully lift before we can do anything, something that Dexter noticed at Austin as something holding us back a little.

Dexter began working on the drive base a little bit. The goal is making the drive base about 5 units wide so we would fit an entire large ball in between the wheel base.

The 5 unit width is a challenge, because there has to be a one inch wheel, a sprocket, and no interference with chain or metal touching the wheel, so it may not be possible to get it under the 5 unit goal.



Recorded By: Dexter Snacks: Chz Squared Page:

TASKS REFLECTIONS

Work on building the drive base, the 5 unit goal is becoming quite an issue, and Dexter has gotten it as narrow as possible using a variety of spacers and axle locks to get the spacing just right for the sprocket and wheel, but nothing seems to work.

We are starting to rethink the 6 motor drive idea, because Aidan built a mock‐up arm using one motor on a 7:1 gear ratio and it seems incredibly weak for our purposes, so we will inevitably need a second pair of motors on the arm. Not only that, but the width requirement of the drive base is making it difficult to include a sprocket in the “equation.”

Revert our drive base from the sprocket method to direct drive – one motor to one wheel, using only 4 motors and adding the other 2 leftover motors back to the arm. This incredibly simple design will hopefully help our robot hang easier since there won’t be very many metal parts and connections being made.

This will make each side of the drive base incredibly narrow, and will help us fit the arm between each side, giving us a lot more freedom with the arm. In addition, not having a motor block on the robot means a simpler mechanism for powering the wheels, and thus, less weight, something that is becoming increasingly crucial to our robot.

Aidan mocked up an arm using one motor for power and a 7:1 gear ratio like we want, he also mounted it on a 5‐wide c‐channel to simulate the drive base we’ll be building.

The 7:1 gear ratio means the arm is much weaker than on our previous two robots, with an increase in speed as the benefit to this speed increase. But as we’ve seen in competition, Toss‐Up seems to be a game of speed and efficiency rather than blocking and defense – whoever scores the most, the quickest, and the soonest will often win. Unfortunately the gear ratio means we will have to strengthen the arm somehow and make our robot super lightweight in order to hang.




Early build of the Omni‐Drive

Aidan’s simple mock‐up of an arm with a 7:1 ratio




TASKS REFLECTIONS

Dexter worked on the drive base some more, making it so that the entire base uses no chain or sprockets in its construction, and the motors attach directly to the omni wheels. The new design is 2.5 inches wide, not including the motor which is attached right on the outside of the 2.5 inch wide base. The new design grants us a lot of freedom with our arm and intake which will fit inside the drive base. J.T also helped Dexter by replicating the other side of the drive base, ultimately finishing it during this meeting.

The motor mounting system we are using isn’t easily removable like we’ve done in the past – using standoffs to mount a small 5‐long 1x25 pieces that are attached to the motor, we have used this sort of method a lot in the past, but since we only have one motor per wheel with no chain and complicated mechanisms, detaching the motors if any problems arise won’t be an issue. Additionally the increased freedom with our arm will help us focus on creating an arm that isn’t super complicated and an intake that can manipulate the large balls.

Aidan worked on a pneumatic mechanism that would assist our arm with hanging since we’re really unsure about our robot’s ability to hang even with 4 motors since it’s on a 7:1 gear ratio. The hang assist would shut off the pistons from the air tank so they could move freely until activated, and then contracted and expanded via the controller once activated.

Aidan is very unsure about the hang assist since it would be very strange to attach the one directional piston to the rotating linkage arm and also be able to utilize the piston’s power to actually translate to lifting the robot. We’re hoping that we won’t have to use the piston assist and only motors, but we’ll have to build a really simple robot that doesn’t weigh very much at all.

The Drive base in its current configuration


Date: 11/22 and 11/25 Start Time: 3:30 End Time: 5:30


TASKS REFLECTIONS

Create and attach a very light weight but mildly rigid tower to the base of the robot. We ended up using 2, 2‐wide c‐channel for each side of the tower and we have two connected, large, low strength gears to act like a high strength for our 7:1 gear ratio. We reinforced the tower from the front and the back with aluminum L‐channel that is also connecting the two sides of the drive base.

Our design for the tower is sufficient for the gearbox we are creating and since it uses such a small amount of metal, it furthers our goal of making the robot incredibly lightweight. In addition, using the L‐channel in front of and behind the tower provides support in both directions, something we usually don’t have, or we have it but it’s not a very good system. This one is screwed in on 3 planes, adding a greater level of rigidity to the tower and thus, the arm.

Design a linkage arm for the robot that lowers in between the two sides of the drive base, this gives us a lot of flexibility for the actual linkage design.

Our linkage will most likely stay with the usual 8‐bar design, or even be reduced to a 6‐bar linkage. The only clearance requirement we have is a motor at the front of the robot which should be really easy to overcome since our drive base is only a measly 13” long, so there is even room in front of the motor for our arm to drop down to the ground. We may still create the piston assisted lift, because we have the drive base area to mount the mechanism and it would almost certainly guarantee hanging.

Aidan prototyped the arm early in the meeting, creating a linkage that only makes our robot 15” long and the design we used was an 8‐bar. Hopefully, we will be attaching the hanging mechanism on the back of our intake instead of the arm, because then we would need to have the hook extend above the intake area of the arm and could impede large ball intaking like our last robot.

Our linkage design will allow our robot to have a roller mechanism that can outstretch 3 inches in front of the robot, but since the space in between each arm is so small, it might be challenging to create a mechanism that can manipulate the large balls and one that flips up and down before the match, because we can’t create the whole mechanism in this small 3” space we have allotted ourselves, what it does is make the whole design process a bit easier since we now have space to work.

Attach the brain, power expander, and the two batteries to the robot.

We tried attaching the batteries in a way that wouldn’t affect its center of gravity.




C‐Channel tower with the gearbox installed The arm, fully contracted

Brain and power

expander mounting




The arm, fully extended Closeup of our arm float – a simple 1

inch screw, spacers, and a nylock.


Date: 11/30 – 12/4 Start Time: n/a End Time: n/a


Linkage Arm

TASKS REFLECTIONS

Work on tightening the 2” axles that are connecting all of the linkage pieces.

This will help our linkage be more stable and not wobble during operation. One of the big benefits for this is just general structural endurance of the robot during operation.

Add an arm stop that is directly attached to certain pieces of the linkage. One piece stood off on small (1/2”) standoffs at the end of the linkage and one closer to the point of rotation that is stood off a little more (1”plus a little).

This type of system will help our linkage keep its shape when the arm is fully extended – during tests the arm would collapse in on itself when fully extended which made the lifting very inconsistent and we couldn’t predict where the arm would rest at its max position, it also just looked bad. This new system is very simple and works very well.

Test our arm’s and our robot’s ability to lift itself on the hang bar. We had to re‐program the robot a little, doubling the motor code lines because we think the robot wasn’t utilizing all of the motors, this was confirmed when we saw that only two of the wheels were actually spinning.

With the motor code doubled, our arm was able to lift our robot, but not fully and of course it won’t stick in the up position. The lift is a little weird; the robot’s arm doesn’t fully contract so building some variety of stop mechanism won’t be easy.

Build an arm stop/catch that will keep the robot suspended on the bar – it can be passive or active, using pneumatic pistons.

The piston method we initially tried is directly attaching the pistons on the arm like a sort of lift assist we were thinking of using before testing the current robot build, but there doesn’t seem to be any good place to put the pistons, unfortunately. The passive method seems like it would be simple and easy to do (hooking the arm to the drive base when the arm lowers as it hangs).




Arm fully extended, with arm stops installed

Arm fully contracted, ready for intaking




Intake (“NZ‐style)

TASKS REFLECTIONS

Build an intake using the very common “NZ‐design” and add the extra, smaller wheel at the top of the axle that connects the motor to the main intake spinner.

This design is really effective for picking up the bucky balls, but not necessarily best for the big balls, but currently it’s the easiest, lightest, and most effective method we have tested and come up with. The unfortunate thing about this competition is that basically every team has the exact same intake design and robot design.

Test different orientations for the motor that does two different things:

1. Keep any non‐moving parts out of the way of the big ball from being took in (our last robot had that big time, there was a large metal piece obstructing the big ball and the motor was mounted on top of the intake mechanism which also obstructed the big ball)

2. Have enough clearance off of the ground so that none of the intake pieces drag against the ground.

In addition to those things we need to have the intake tensioned inwards using a hinge as the rotational joint, and tensioned down so the intake flips down at the beginning of the match.

The biggest problem with our last robot when it came to the intake was not being able to manipulate the large balls, this new one does very well, we used a rubber band covered roller for the large ball mechanism and once we “capture” the big ball, all we have to do is spin the intake and the big ball gets sucked in. As for the small balls, this mechanism works as well as the last robot: very well. This intake mechanism used a lot of bearing blocks and an extra little mount for a chain and two sprockets since we have the motor at the base of the intake and the roller at the other end. As a result of all the bearing blocks (and ½” screws and nuts) the robot has become incredibly unbalanced, proving a huge challenge for us just before the competition.

Lighten the intake by simplifying it a lot – we basically took a 10‐long aluminum c‐channel, attached the motor at the bottom of the c‐channel (closer to the ground, so there is very little clearance) and have the intake rollers extend up on the other side of the c‐channel.

By doing this and moving the batteries to the back of the robot as opposed to the middle where we had them, we minimized the weight imbalance we had, but it still is a slight problem since our drive base is so short and easily tipped over.




Here the entire intake mechanism can be seen, with the large ball and bucky ball rollers

installed – the large ball rollers may change to use VEX mesh in the future

In this picture, the intake’s hinge, shaft (for vertical rotation), and inward tension rubber bands




Other Changes from Thanksgiving

TASKS REFLECTIONS

Wire the robot in order to test all of components we’ve added, like the arm, intake, and to see if the robot hangs‐ which it did.

The wiring went well, there was a little issue with the arm wiring since Dexter wired the arm, and since it moves so much and has so many different areas for wires to get damaged, and he ended up not doing a very good job, ending with a broken motor controller.

Add a hang lock mechanism using pistons to latch a small 5‐long aluminum c‐channel onto one of the vertical members of the arm, it will be extended upwards at the end of the match so the 5‐long flips up (it will be up‐tensioned) and then the piston will be retracted and lock the arm in place.

This mechanism is relatively simple, and as long as the arm works how we think it will, it will work. The only problem is that if we extend the arm and the lock flips up, we have to hope the arm will push it back down again and not get stuck or impeded by the mechanism.

We moved the batteries to the back of the robot and only had them attached via the battery zip‐ties, and they snapped during operation. So we devised a new method of securing them using 1x25 pieces as a sort of holster for them.

The method we devised is much more effective at holding them, and it is still very easy to put them in place. Unfortunately, this just adds more weight to the base of the robot which is something we don’t necessarily want at this point.

Here the battery mount can be seen using 1x25 steel


Date: 12/7/13 Start Time: 6:30 am End Time: 9:00 pm

Recorded By: Dexter Snacks: Pluckers and Concessions

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Killeen Toss Up Competition

TASKS REFLECTIONS

The night prior to the competition, JT and Dexter worked on a hang lock mechanism for roughly nine hours, modifying the mechanism over and over again. In the end the mechanism would have worked, but it made the robot too heavy and, when attached, the robot could not lift itself up anymore, so we decided to take it off and not utilize the hang during competition.

It was really unfortunate to find out that the one mechanism that would allow our robot to hang made it impossible to hang in its current build state, the gear ratio we are using (7:1) doesn’t supply enough torque to lift up the robot. After looking at Anderson High School’s (2158M) robot, we have begun to think that just attaching the piston to the arm and base will be enough to assist and lock the robot in place. We tried this method before, but decided not to use the idea since the range of motion of the piston might not be enough for the arm to lift the intake the full 24 inches to stash bucky balls.

Compete in the Killeen Toss Up Competition Reflection on the competition will be below/on the next page.

We were the runners‐up in the finals of the competition with Pastoral Invasion (4252A) and the AustinCans (2158M). The alliance we lost to was led by Team Floyd 2 (400x).

Pastoral Invasion competed the entire time during finals and we switched out with the AustinCans. It seemed like our major downfall was our robot’s inability to hang as well as our lack of a good autonomous for this competition. We did, impressively, win the autonomous section for almost every match, except for a couple against the Floyd alliance. But we won’t be completely rebuilding our robot before the San Antonio Competition so there will be more time to practice and program an autonomous for our robot, this will help level the playing field at a competition that will be as fierce as San Antonio is shaping up to be.

Planned Changes: located underneath the competition reflection.

We saw a couple of ideas we would like to work off of and some changes we already knew we would make, even without going to the competition.




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Killeen Toss Up Competition Reflection We went into this competition knowing our robot was inferior to some of the robots that would be there such as the AustinCans senior team and Pastoral Invasion. But we also knew the competition was pretty low level and that it wouldn’t be super competitive so we were pretty sure there was a good chance of getting to finals. Our original strategy was to be fairly competitive, but try to stay out of the top 8 because the AustinCans, Pastoral Invasion, and our team have forged an out of competition alliance via online social networking and friendships formed at previous competitions. Our actual performance went something like this: at first we did well, there was little to no competition because most of the competition was push bots. Then we began making small changes to the robot like upward tension on the arm since we didn’t have to hang, but magically this made our robot tip forward really easily so after tripping through a match we scrapped the idea. During another match, against our B‐team, one of the gears powering our arm slipped out of place, this disabled our arm for the entire match, meaning we were a glorified push bot against our own school’s team. Then towards the end of the competition we picked it back up, reverting any changes we made so our robot simply picked up and stashed bucky balls and large balls. In addition, Dexter, the robot’s driver, relaxed a bit and was able to easily score balls and defend against opponents. In another match we were up against both the AustinCans and Pastoral Invasion and our robot was partially non‐functional due to the upward tension we added to arm prior to the match, so we didn’t do well at all during that match. In the end we placed 12th with a record of 3 wins, 2 losses. The finals were just a simple 4‐alliance semi‐finals then finals, so a total of 12 teams. We were approached by 400x twice with them asking us how well we competed and what our robot could do. But in the end our team got picked by Pastoral Invasion in addition to the AustinCans. We advanced quickly through the semi‐finals, easily beating our opponents during driver control and autonomous. In the finals, 400x and their alliance proved to be a very good opponent, 400x has come leaps and bounds since last year, especially in their driving abilities. We lost the first match between Pastoral and AustinCans vs. Floyd and 2880A. Then when we were up, we flattened Floyd and their alliance partner. In the third match, a repeat of the first one, we lost mainly due to some rough play from 400x, in other words, they were pinning Pastoral’s robot against a large ball for over 10 seconds and never backed up more than 3 inches when called on it. This leads me to my next point about the competition, the organization, judging, and reffing of it. The downside about this competition was the competition itself. Starting with the organization of it, due to ice that never formed, it was delayed 1 hour, then the competition itself didn’t start until 2 hours after the planned start time. Between the first few matches there was about a 20‐30 minute delay due to technical troubles and slow counting by the referees. In addition, the referees didn’t seem well trained and didn’t know the rules of the competition, even something as simple as putting a bucky ball back into the field if it went over the barrier slipped the ref’s mind. The finals match I described above was another great example of the referee’s inability to recognize simple rules that were being broken really badly. Early in the




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competition the AustinCans went up against our M‐team (8756M) and M‐team got called for pinning and instead of just deactivating their robot for the match, the match official disabled every robot on the field. Besides the poor officiating and refereeing, the judging and award giving was done relatively poorly, at every competition we’ve been at the wealth of awards is evenly distributed amongst teams, so Excellence goes to one team and Design to another. However this competition was different, Pastoral Invasion (4252A) was awarded the Excellence and Design award. Overall this competition was relatively inadequate on the scale of normal, good competitions we’ve been to, overall the lack of good competition and the bad refereeing and organization made this competition less than satisfactory. Planned Robot Changes:

1. More stable drive base a. Possibly lengthen the base or add a anti‐tipping mechanism on the front

2. Redesign the intake mechanism a little so the big ball intake and the bucky balls a. Offset intake rollers so the big ball roller is in front of and wider out than the

bucky ball roller (see attached illustrations). 3. Paint the robot black 4. Make sure the robot hangs by adding pneumatic lift assist.

a. Lift and lock – may require a linkage redesign 5. Multiple autonomous programs for both sides of the bump 6. Possibly meth motor the intake 7. More nylocks, fix and tighten certain elements of the robot, and improve other areas 8. Help the other 2 teams complete their robots before the San Antonio Competition. 9. Practice and test the robot thoroughly.



Recorded By: Dexter Snacks: Provided lunch Page:

TASKS REFLECTIONS

Compete in the San Antonio VEX competition sponsored by the U.S army. During the competition Dexter took decent amount of pictures of robots at the competition, but none of the competitions that our team competed in, since he drives the robot.

This competition was one of the better ones we attended, the competition was good, meaning the other teams that were in attendance were either really skilled or had some interesting robots. Teams that were there included 9090 (T‐Vex), 2587 (DiscoBots), 4252 (Pastoral Invasion), 2158 (AustinCans), 400X (Team Xtreme), and two really high achieving driver skills scores from 6966 (GonBotz).

The competition was arranged into two separate divisions, the RECF Division and the US army division, we were placed in the US Army division which we quickly realized was the far more inferior division. US army, besides us had 400X whereas the RECF division had 2587, some 2158’s, 4252, 9090, and more teams. We knew that in the finals, the winner of the RECF division (which happened to be 2587Z and 9090C) would win the competition. As far as our team went, we got first pick by the 8th seed alliance, but were about to be the 1st seed’s second pick, in other words we would have ended up being finalists.

We were slightly bummed about our performance in this competition, because we went into it thinking we had a good chance of doing well. Based on our friendship with the DiscoBots, it was entirely possible to be their second pick had there been no division play, we also have built up a strong friendship with Pastoral Invasion. The main reason we were hoping to do as well as we could at this competition was because it was a really good way of judging our level of competitiveness in a competition similar to what the South Texas Regional will be like. Of course 9090C won’t be there, so DiscoBots will have to choose someone else for their alliance.

We figured out several problems with our robot ranging from communications issues like we’ve had at every past competition (the controller and cortex disconnect for a second then have to reconnect fully before continuing the match). Aside from that, we had the same front tipping issues we had at Killeen since the drive base wasn’t changed at all, we also had problems that we noticed while scrimmaging with 2158M the night before, with our intake: it seems to fling the bucky balls out in a rather irregular

We really have no way to fix the communications issues that have been plaguing our team the entire season, aside from getting new VEX keys (which are expensive and touch‐and‐go on whether or not they work out of the box) we don’t know any way to fix the problem. Solving the tipping problem will be as simple as making the drive out of a full length 35‐long c‐channel, and so far the best intake idea is the one we were using at the beginning of the year, but just modified a little bit for




pattern which means our scoring ability is hindered. Dexter also noticed that the robot was much slower than all of the other robots on the field, which put our team at a bit of a disadvantage.

optimal bucky ball picking up. The big ball intaking was also a little rough, but that’s just because of obstructions on the intake structure itself, so rebuilding it will help a fair amount.

Pre‐match preparation

Army Division Fields ready for play!




Our finals alliance captain 400X high hanging with large ball

US Army Division Finals


Date: 1/7q/2014 Start Time: 2:40 End Time: 5:30


TASKS REFLECTIONS

Dexter started building the new drive base for the robot using pieces of 35‐long aluminum C‐channel instead of the old configuration we used that had 25‐long C‐channels.

This new design that obviously isn’t the most revolutionary, will help drastically reduce the tipping problem our robot has been having in competition. The problem that tipping has presented for the team, and especially Dexter, the driver, is that he has to focus more on not tipping the robot than actually driving and picking up bucky balls. Hopefully the new design will help him drive better than he has been.

Aidan worked on reinforcing the tower of the robot with nylocks, by doing this we can ensure less work on the robot – tightening loose screws – and more time practicing and focusing on competition‐oriented tasks.

Using nylocks more often will help improve the robot’s endurance in a competition setting where the robot is constantly being driven and carried around, in addition, help make connections more rigid.

The idea of gearing the drive motors on our robot for speed rather than torque was discussed because we’ve realized that there aren’t many pushing matches going on, rather there is an emphasis on getting to the tube quickly and efficiently to score bucky balls. We agreed that a 4 motor speed drive would be feasible and we would do this once the drive base is finished.

Having a speedy robot can help us be more defensive and offensive at the same time, offensive because we can quickly transport buckys across the field and defensively because we can get to the tube and block it from the opposing robot faster. Overall, speed has become the apparent deciding factor in a good robot, with 400X being the glaring exception because it is only heavy, strong and slow.

Dexter has been discussing and formulating tactics for the South Texas Regional that is coming up at the end of February by compiling a list of teams going to the south and north texas regional, currently only 5 teams have qualified for the north competition, and 22 for the south competition. We are unsure whether we can go to the north or the south since our team is located in central Texas. Dexter also talked to 4252A, Pastoral Invasion who was crossed by DiscoBots at the San Antonio competition and now wants revenge.

Our team has been establishing a close friendship with 4252A, Pastoral Invasion, so there is a great possibility of being with their team at the South Texas Regional, the problem is that, combined, we may not be good enough to beat out alliances with teams like 400X or 2587Z (Disco). If we had the opportunity to go to the North Texas Regional, Pastoral has a really good connection to 9090C (T‐vex) so they could be together with our team as a second pick, but that’s only if we can go there. Overall qualifications are really confusing.


Date: 1/7q/2014 Start Time: 2:40 End Time: 5:30


The tower and arm without a drive base

The tower and arm with the new 35‐long drive base




TASKS REFLECTIONS

Continue working on the drive base design, today Dexter finished the other side of the drive base he started during the last meeting, this meant screwing both sides together with standoffs then attaching the base assembly to the tower. No motor mount solution has been discuss

Our new design for the drive base will help significantly lower the problem we have had with tipping at past competitions. The unfortunate part about this design is that we have to adjust the motor mount for the front wheels, because having a direct drive isn’t possible due to the linkage terminating right where the motor would be, previously we designed the linkage to float over the motors. We think internal chain will be necessary to power the front wheels, so the two drive base sides will need to be widened to accommodate the sprockets and chain.

Dexter thought about how to improve the tower design of the robot. More specifically, how to mount the motors on the outside of the tower frame. It will be difficult because our motor mount method uses standoffs and a 1x25 to attach the motor, that way it is much more modular than straight attaching the motor to the tower. But unfortunately the spacing of the screws for the motor mount combined with the spacing for the gearbox axles makes the bearing blocks very difficult to place and choosing where to attach them and what to attach them with will be difficult.

The method of attaching the motors on the outside of the tower frame will make it easier for us to maintain the structural integrity of the gearbox. In addition, the way we previously attached the motors meant that two motors were facing back to back (literally touching each other) which meant they were possibly overheating, or could have overheated faster. But mostly, the previous mounting method was easy, but was not efficient for performing normal maintenance on the gearbox motors, mostly tightening them (and the ones on the inside of the gearbox loosened incredibly quickly).

Dexter took the linkage off of the robot to make working on the gearbox and drive base much easier, this was also inevitable since we would have to redo the linkage anyways. Aidan started taking apart the entire linkage and intake (which will also be changed quite significantly).

The linkage will hopefully not be too difficult to redesign, and if we get everything done quickly (the drive base and gearbox) Aidan can focus on making a really good linkage, which again will probably be an 8‐bar like we’ve had on every robot so far.




Bare Bones Robot Empty Gearbox

Intake being taken apart




TASKS REFLECTIONS

Dexter removed much of the pieces involved in the gearbox, including the motor mounts, some of the bearing blocks and the potentiometer on each side. This provided a good space to work on redesigning the gearbox. Then the spacing for each axle was figured out, 3” between the two powered axles that are connected to metal pinions (12‐tooth) and an axle right between those two pinions (1.5” away) for the 84‐tooth gear. This creates the 7:1 gear ratio we’ve had on many iterations of the robot.

The new gearbox is required because of having the two motors attached on the outside of the tower frame, because they are separate from each other, requiring two 12 tooth pinion gears, one for each motor, to power the 84 tooth gear. This will also help us troubleshoot any issues we have with the lift, seeing if one of the motors isn’t working or is spinning the wrong direction, our last design relied on one axle going through both motors.

Once Dexter finished the new gearbox, Aidan copied it on the other side of the robot.

Two people working on the robot seems ideal, because one person can copy what the other did, often times having three people working leaves the third doing nothing the whole time.

Aidan began designing a way to power the drive base, especially the front wheels since the rear wheels will likely be direct drive with no chain. What he found after minimal investigation about our current design is that the drive base needs to be widened slightly in order to accommodate a chain and sprocket powering method for the front wheels.

We ended on this note, so during the next meeting we will have to make some modifications to the drive base, widening the frame that supports the motors and wheels. Unfortunately this is relatively difficult at this point because most of the attachments we have to change use nylocks, so it’ll be a huge pain to change anything.




Right hand perspective of the left gearbox Left hand view of the left gearbox




TASKS REFLECTIONS

Before school ended Dexter finished widening the base of the robot which included changing out the standoffs on the unfinished side of the drive base to 3 inch standoffs and then moving the 1 inch standoffs on the rear cross beam inwards by a unit to account for the widened base.

Doing anything related to the drive base is painful because most of the connections we are using are either extremely tight or we used a nylock, so this widening process took a while. But fortunately the wider base will allow us to add a sprocket‐chain system to power the front wheels.

Dexter also figured out a method for mounting the motor and connecting the front wheel to the motor via a sprocket and chain. This involved, for one thing, taking out the front set of standoffs that hold the drive base together, so once the whole robot has been completed, including the arm and intake, we’ll figure out a method for connecting the two sides again, preferably with a 35‐long cross beam that spans both sides of the drive base to not only hold the two sides together, but to make the entire drive base more rigid.

Once Dexter figured out how to mount the motors for the front drive, he attached the motor, then let Aidan finish working with the chain system, spacing for the wheel, and general attachment of all the related parts. Dexter will finish attaching all of the motor and wheel related parts tomorrow, since it’s a very simple process, but we ran out of time and weren’t able to finish everything for the drive base.

The idea of starting the linkage designing process was brought up by Dexter, but nothing really got going since we need to have the drive base complete and wheels attached.

Aidan is the linkage designing champ on our team, so he really does have the sole responsibility for designing and building at least one side of the linkage, the other side can be easily replicated by someone else on our team.

Sprocket and Chain Mechanism for the front wheels


Date: 1/15/14 Start Time: 2:45 p.m End Time: 5:30 p.m

Recorded By: Dexter Snacks: Page:

TASKS REFLECTIONS

Finally finish building the drive base by re‐gearing all of the motors in exchange for speed rather than torque. Then test the speed of the robot once all of re‐gearing is finished, but with our newly decided wiring configuration.

Aidan re‐geared the motors since he is really the only person on the team that knows how to do this, it went pretty fast, and all of the motors got reattached to the robot for testing later on during the meeting.

Undo most of the wires on the robot, including sensors, motor controllers, and motors that were directly connected to the cortex (through ports 1 and 10). Then remove the power expander in favor of less weight and lower battery power. Dexter did this then wired up the drive base to test it.

Removing the power expander was the main goal of rewiring the robot, without a power expander the robot won’t be able to draw as much power as it did before, but since this competition seems like a relatively low stress one for the batteries, we decided to opt for a low‐weight solution using only one battery connected to the cortex.

Once Dexter got all the wires plugged into the cortex, he tested it out with the leftover program from the San Antonio Competition. It seemed to be a bit faster, but its drive‐path was slightly curved and we found out that once of the motors hadn’t been switched out for a speed motor, in addition we found that some sort of ghost value was left on the motors after driving in a direction, making them more difficult to hand spin (when the robot was on) in only one direction. To change this, Aidan began to figure out a programming fix to this problem, but didn’t want to start during this meeting due to time constraints as well as weird RobotC errors that started occurring.

After changing out the motor, we didn’t get to retest the robot’s drive, because we wanted to get right to work on fixing the programming issue that cropped up. But it does seem like the motor we used for the “slow” wheel that was geared for torque is a rebuilt one (we have rebuilt many of our motors due to various damages, sound issues, and circuitry issues, but this motor in particular seems to have a large amount of friction internally, which could be a contributing factor to the lowered speed on that side of the drive. The programming on the other hand probably won’t have too much effect on how the robot drives, except possibly making it a little more responsive since it won’t be saving ghost values like it was.




Back of the robot with the new wiring configuration (no power expander)

Finished drive base, with speed geared motors




TASKS REFLECTIONS

JT replaced the weirdly functioning motor on the back of the robot. Hopefully with some testing, the new motor will prove to be much better in terms of actually having increased speed.

After spending a very long amount of time replacing the motor, since it’s in a rather precarious spot for using screws, we realized that we hadn’t actually geared the motor for speed, meaning we have to take off, re‐gear, and re‐attach the motor.

Aidan began working on the linkage arm, first he tested the feasibility of a 6‐bar linkage, but the height advantage isn’t enough to rationalize changing the already functioning 8‐bar design we’ve been using this entire season. So currently Aidan is mocking up a new 8‐bar linkage that will take advantage of all the extra space we gained by having a sprocket‐chain drive for the front wheels, a design that places our front drive motor nearly in line with the tower of the robot.

Hopefully the increased room we have for the linkage will allow Aidan more freedom with the linkage, being able to stretch it all the way down to the ground on the first link and not having to span anything (like a motor) on the way to the end of the linkage should also help Aidan make the linkage with more ease than on previous builds of the robot. The only current problem that is foreseeable with the present iteration of the robot is that the intake will have to be rather narrow to fit within the linkage arms of the robot.


Date: 1/31/14 Start Time: 4:30 pm End Time: 10:00 pm

Recorded By: Dexter Snacks: Cheez‐Its Page:

TASKS REFLECTIONS

Aidan began designing the linkage with parts we had on hand, including steel since one of our other teams has begun using exclusively aluminum for their robot as well. This meant that the designed linkage was quite crude and to be completed later.

With the full length (35‐long) drive base we have, in addition to the widened base (since we’re using chain to power the front wheels) the arm has to go between the two sides of the drive base and thus is narrower than before, which also means a narrower intake, which shouldn’t be too much of a problem since our intake had to be narrower anyways.

Dexter began assembling one side of the linkage once a new shipment of parts came in, then when JT came in, both of them assembled the rest of the linkage.

This linkage is really difficult to assemble, because we are using 1.5” screws for all of the rotation points and nylocks to keep them in place, which means screwing about 0.5” through a nylock. Unfortunately as well, after attaching the linkage to the robot, Dexter realized the linkage, reaching to the end of the drive base and the edge of the size constraint, was too long for us to even attach an intake to the end since there was so little space allotted.

The day after finishing the original linkage, Dexter quickly designed a new one that was 5 units shorter on the first two bars, shortening the overall linkage 7 units in horizontal length, providing ample room for an intake and roller.

“What bothered me more than assembling two linkages was assembling the second linkage immediately after finishing the first one.” In conclusion, nylocks are very difficult to screw in and out of. But the linkage is promising now, which is what matters.

Aidan designed a new intake solution we haven’t used before which is made of a downward facing motor attached to a c‐channel powering gears that are underneath the c‐channel, the gears then power an axle with our big ball roller over the c channel and the bucky ball roller underneath the c channel. But the biggest change is a 45 degree angle gusset connecting two c‐channels (one that is 7‐long, one that is 5‐long), so the motor is rotated 45 degrees inwards, meaning it

The new intake mechanism will be good, because it seems to be the perfect combination of non‐interference with the ground (no more upward facing motor dragging along the ground) but also non‐interference when intaking a large ball, it has been a running problem with our robot since the beginning, that a downward facing motor always gets in the way of the big ball when being taken in. Hopefully, since this is the day before the Austin Toss Up Competition, we will be able to finish the




won’t interfere with the big ball when intaking. As of 5:45 p.m, the day before the competition, as there are still 4 hours left in the work day, the intake could radically change at least 3 times.

robot with relative success in the intake department. But, as we have found in the past, the intake can change a lot, so whatever is currently planned can change a lot by the end of the day.

We finally fixed the drive issue that we were having (one motor turning slower than the rest and causing the robot to arc drastically to one side) at first we thought it was a programming issue, but upon replacing the motor with a brand‐new, out of the box motor, it was just a faulty motor causing the problem.

After replacing the motor, we tested the robot with a questionably charged battery and it was super speedy, a really good thing to have, we’ve realized, after participating in several competitions.

Aidan worked on programming for a bit, mostly wrestling with RobotC, getting it to work with the USB ports on the computer as well as get the wireless connection with the computer to work properly in order to download the program on the robot.

As Aidan has said before, RobotC isn’t the best programming language because most of the time spent “programming” is just wrestling with the program itself and getting firmware downloaded and getting the computer to recognize the cortex as new hardware.

Linkage in the down position




Linkage about halfway up Gear box close up

Intake Design


Date: 2‐1‐2014 Start Time: 4:30p.m (Friday) End Time: 7:00p.m (Saturday)

Recorded By: Dexter Snacks: Pizza Page:

Austin Toss Up Competition (2‐1‐2014) TASKS REFLECTIONS

On Friday the team made a concerted effort to finish the robot before competition, by having everything finished except the intake, we worked on the intake for the entire day. Starting at about 4:30 at school and ending at Aidan’s garage around 10:15. By the end of the night, we had successfully created a feasibly working intake using 45 degree angle gussets to accommodate a large ball better than our previous intake designs had. Due to the reduction in length of the arm, the intake was also easily able to fit within the size restraint of 18 inches.

It was very good that we were able to get everything finished on the robot, but unfortunately we weren’t able to test any of the new mechanisms that we had installed, especially the intake which was completely different than any intake we’ve made before. In addition to working on the intake, Aidan was able to quickly program and install potentiometers on the arm again so we still have our tried and tested arm stabilization program on the robot (see the cheez‐it box pages for some stabilization math). After finishing the intake, Aidan was able to test and make sure the arm stabilization and the drive worked properly.

After checking in at the competition Saturday morning, we made some minor modifications to the intake to make sure it didn’t expand outwards and rub against the front wheels of the robot. After the first match we also realized that the change Dexter made to the linkage made it just barely tall enough to reach the tube, the big problem was linkage slop and a droopy intake that couldn’t even get over the tube. Throughout the day we made many minor modifications to the intake in order to get it working as good as possible for the current design. Otherwise, the current iteration of the robot is very good, nothing mechanically wrong happened to the gearbox, lift (aside from the inadequate height), or drive. After realizing our Autonomous didn’t perform well and flipped our robot over backwards once, Dexter and JT decided to use a closed skills field to program a fully automatic (and legal) autonomous that knocked over both large balls into the high zone.

We realized a few things at the competition, the biggest was that the speed increase we got from the re‐geared motors gave us a nice edge in competition as well as a more responsive robot overall. The gearbox also performed really well when we did a pretend hang by holding the robot with our hands, as the robot lifted itself up on a full battery, the gears didn’t click once and was able to lift itself completely. The real problems with our robot came in with the intake, as stated, the intake’s concept is good, the 45 degree gussets are a nice addition and help accommodate a large ball, but our less than 12‐hour execution was quite lacking. Besides the robot itself, JT’s ability to very quickly program a new autonomous that was completely automatic was very impressive, and came in very handy during finals.




The competition was so small that finals only consisted of 4 alliances, we ended up getting picked 2nd by the first seed alliance, captained by 4252A: Pastoral Invasion. In the first match 2158M and 4252A won 92‐7 and when we switched out with 2158M for the second match, we won 72‐4. In finals, 2158M broke down halfway through but our alliance still won, and in the second match of finals, we de‐scored a large ball in the middle zone in the last second and won the match 46‐45, meaning we de‐scored the tying point. See images below to see the current intake design.

Finals went very well for us, and once again displayed the importance of intra‐team socialization, by forming a friendship with Pastoral Invasion and the AustinCans, we were able to be in an alliance with them and ultimately win the competition.

One of the other teams at our school, 8756B, amazingly got the programming skills champion trophy for their 12 point autonomous they use during normal match play. Unfortunately, though, this will be their last competition of the year as they did not qualify for the South Texas Regional. But one of our beginner teams, 8756M did qualify for South Texas, so he’ll be accompanying us to the competition with his robot.

This year has been quite a new experience, with two extra teams; 8756B and 8756M, we have had to balance the distribution of parts, especially with 8756M, who decided to make his robot out of aluminum, a very valuable part for us. So overall, it has been very interesting both in terms of the balance of parts we’ve had to strike, as well as slowly mentoring both of these teams to the level they are at now. Hopefully 8756B will stick around and continue the robotics program at our school, because all of the members on our team and our M‐team (Cesar Reyes) are seniors, whereas the B‐team has 2 freshmen.




Closeup of Intake Spacing

General View of the Intake on the Robot

Top view of Intake (you can see the gussets, roller config, and intake basket)




Team Reflections Dexter “The competition was really fun, almost any competition with Pastoral and Anderson turns out being pretty enjoyable. The downside to this competition, however, was the crazy amounts of beginning Anderson high school teams that weren’t very good at all, lots of push bots and no shows. This also means that we really didn’t get a good chance to test the mechanisms in a truly competitive environment. But, at least we know how to move forward with the robot, what do with the intake, the drive base, and a really solid idea for hanging!” Aidan “I think the intake works surprisingly well, for being built so quickly, but comparable to other robots its ability to pick up large balls was quite similar to other robots, and its ability to pick up bucky balls could have been done better. In terms of success at the competition, I was surprised about how well we did, but as far as actual robot performance, it performed as well as I would have expected, and it definitely needs improvement.” JT “I don’t feel like we performed that well, but I’m glad we had an autonomous by the end of the competition that was legal and didn’t get us tipped over. Dexter seemed to be having some issues with the intake and his driving, also.”



Recorded By: Dexter Snacks: Thin Mints Page:

Meeting (1‐3‐2014)

TASKS REFLECTIONS

Before the meeting really began, Dexter drove the robot around a little, slaloming around table and chairs mainly, in order to get even more accustomed with driving the robot.

One thing Dexter noticed about the intake while driving around and picking up bucky balls was how bad it was. The 45 degree gussets move the intake rollers so close together that they act more like a wall than an intake, so the rollers really need to be more spaced out. Otherwise, the robot is great.

At the official beginning of the meeting, our sponsor talked about all the possible awards for the South Texas Regional, mostly going over the design and excellence award, two things we could possibly have a shot at with our notebook and a focus on competing well, actually successfully doing the skills challenge, and keeping up with this notebook.

Based on some of the things we read on the design notebook requirements, Dexter decided to include a separate team reflections section to get each individual team member’s thoughts on the meeting or competition that happened on a certain day. Another plan we have for going forward is to get some CAD drawings in the notebook and a lot more sketching done a regular basis.

During our team meeting we also came up with a gameplan for the next couple weeks: 1. A big priority for the robot is to add

hanging or a launcher 2. We reapportioned duties on the team:

a. Aidan will be the head builder and designer of the robot

b. Dexter will spend extra time perfecting the notebook

c. JT will work on programming. 3. We need a fully‐fledged programming

skills routine for the robot that utilizes the gyroscope we have installed.

4. Fix the intake and any other small problems on the robot.

By reapportioning the job of programming to JT, we all think more can get done, more efficiently, because often times, Aidan and Dexter will work on the robot and JT will have nothing to do, so by looking into our code, adding comments for judges and others to see easily, and researching how to program our gyroscope, he can better use his time on the team. As for the topic of hanging vs. launching, we have to pick one in our current situation, because we only have 1 tank and 2 pistons.



Recorded By: Dexter Snacks: Thin Mints Page:

Pros and Cons of Launching Vs. Hanging

Launching Pros:

Helpful for Scoring/Descoring Large Balls Helpful for Scoring/Descoring Bucky Balls Can change the point amounts by more than 20 points

Can be used throughout the entire match

Useful for a low‐zone autonomous. Cons:

Requires more tanks than we have

Requires more pistons than we have to have for the best effect

Once we’re out of air, it’s useless

Hanging Pros:

With our planned design, we can hang at any height and disengage it.

Can get at least 5, 10, 15, or 20 points. o Usually it would be 20.

Fairly easy to implement and use in competition

Very very valuable for a programming skills run Cons:

Might not be as valuable as launching in competition

Could possibly destroy the gears in the gearbox.

Team Reflections Dexter ”I think the new team organization, mostly JT’s new position as the lead programmer will help increase our team’s efficiency, I’m also excited about the prospect of having a hanging robot or a launching robot, both would be awesome, but I doubt we have the money necessary for the pneumatics.” Aidan “I’m excited to be able to start designing and building new, complex mechanisms for the robot, specifically for hanging or launching, for the entire season so far we’ve really only done basic things on the robot. I also think it is really good to have someone who is interested and able to program when he isn’t doing anything else.” JT “I am excited to be the new programmer, I’m also looking forward to having new mechanisms, whether they’re launching or hanging.”



Recorded By: Dexter Snacks: Girl Scout cookies Page:

Meeting (2‐4‐2014)

TASKS REFLECTIONS

Today we didn’t do very much on the robot. Aidan began the process of shortening the drive base by 5 units, but could only get one of the 4 c‐channels replaced, the other 3 have to be cut down and we didn’t have the jigsaw, so instead he worked on designing a hang lock mechanism, or as he refers to it, a nefarious mechanism.

Hopefully tomorrow we will have the jigsaw, so Aidan and Dexter can finish shortening the drive base, and then work on fixing the intake mechanism, which Dexter also needs to remove from the robot soon.

Aidan and Dexter talked about the linkage for the robot and how to improve it from the one used at the Austin competition, and they decided that an 8‐bar linkage would probably be good to use again since it also makes reaching the hang bar much easier.

The upside to an 8‐bar linkage, as we have found from every previous competition so far is that it can reach great heights while remaining in a relatively compact form in the down position. The downside is that when the linkage is fully extended, it can get really floppy. But we figured that the bonus of having extra height outweighs the flop and slop of an 8‐bar.

JT worked on programming for the entire meeting, mostly getting some functions for our autonomous sorted out, before this point in time we didn’t have functions in the program so our autonomous was incredibly long, but JT was able to condense about 50 lines of code into about 10.

As the new programmer for our team, JT is already showing his worth, the new functions that he implemented in the program will help us a huge amount in the ease of programming an autonomous mode and a programming skills routine, the next step for him is researching the gyroscope code.

During the meeting we all discussed the possibility of setting up a full field inside of our sponsor’s classroom, for practicing the week before the competition and working on a programming skills routine, hopefully this will work out since it would be incredibly useful for our team, and Dexter to practice his driving.

We have the ability to borrow a field from Anderson High School since they have several from competitions they’ve held at the school. The only problem is that during the school day, two separate teacher s use the room and we would have to move several tables that are used almost daily.



Recorded By: Dexter Snacks: Girl Scout cookies Page:

Team Reflections

Dexter “Having a slightly shorter drive base is good, it’s still long enough to avoid the front tipping problem we’ve had, but now short enough that it won’t interfere with the intake. I’m also really excited about the prospect of having a field in the room” Aidan “Shortening the drive base won’t compromise our front tipping solution, and will also allow for more freedom in intake design. And having a field is good, I guess.” JT “I finished rewriting the autonomous, and I feel really good about it. Having a field would be awesome, because it would help me a lot with programming skills.”

Image of the robot after shortening the drive base




Meeting (2/5/2014) TASKS REFLECTIONS

Dexter finished the drive base early on, he did this simply by taking off all of the wheel mounts, clamping the drive base to a table and chopping off the front 5 units of c‐channel. After doing this, he reattached the wheel mounting mechanisms and tested the robot.

Visually, the robot looks stubby again, like our previous robots from Austin no.1, Killeen, and San Antonio, but with less forward tipping… Although we don’t know for sure if this is solved, because the intake wasn’t attached to the robot when Dexter tested it. There was a slight issue with back tipping, but that hasn’t ever been an issue, so hopefully it won’t be now.

After finishing the drive base, Dexter fiddled with the intake design. He decided to use the same general design with a right angle connector attached to a hinge. What he intends to do is remove the spacers added at the competition, reorient the right angle connector, and change where the up‐down pivot point is for the intake roller.

Dexter didn’t get to finish building his concept for the intake so he’s not sure about how well it will work. But just by eyeballing it, the new position for the intake rollers will place them far enough apart that they won’t interfere with each other like they did at the competition, and they’ll be further above the ground.

Besides fiddling with little things on the robot, Dexter did some practicing driving around on the tile floor of our room, and mostly figured out some fun little things to do on the tile… like drifting!

The benefit of tank drive, as Dexter has now realized is the various and minute driving maneuvers that can be done.

Team Reflections Dexter “Today I was the only member of the team present at the meeting, so I just did what I thought might be helpful to getting the robot finished as soon as possible. I figured the intake would be a good use of my time, as is often the case, we work on the intake a couple days before the competition and it never turns out well.”

Top view of the new intake


Date: 2‐6‐14 and 2‐8‐14 Start Time: 4:30(2/6) & 2:00(2/8) End Time: 5:30(2/6) & 7:00(2/8)

Recorded By: Dexter Snacks: Whataburger Page:

Thursday (2‐6‐14) and Saturday (2‐8‐14)

TASKS REFLECTIONS

On Thursday, Dexter continued working on the engineering notebook – mainly trying to sort out sketches and other images into the notebook that hadn’t already been put in their right place. Meanwhile, Aidan worked a little bit on modifying the linkage, at this point the team planned on making an 8‐bar linkage, but this changed quickly. JT spent his time researching code for the gyroscope, which resulted in some untested successes.

Dexter is hoping that the notebook will help the team gain an advantage for some awards at the South Texas Regional which is coming up in about two weeks, a very short time period for making some pretty major modifications to the robot. Aidan didn’t get too much done with the linkage which ended up being good since the team would soon decide to make a better 6‐bar than the one we used at the Austin Toss Up Competition. JT’s work on the programming is making the team much more efficient with its time, now instead of waiting for a finished robot to program it, JT is working in tandem with the “build team” – mainly Aidan and sometimes Dexter.

On Saturday, there were a few main goals for the day since we had much more time than a usual after‐school meeting: 1. Aidan will design a 6‐bar that uses a

35‐long c‐channel as the main bar. 2. Dexter will assist Aidan and JT as they

need help, since the robot ultimately takes priority over the notebook.

3. JT will continue working on the gyroscope code with his friend Max.

4. Once the linkage is designed, Aidan will work on prototyping a dual hook/launcher mechanism.

On Saturday we started working around 2:30 and ended at about 6:30, we would’ve started earlier but Dexter had to go to an Art Competition. Overall, the day was very productive, because we used each team members’ abilities to the fullest extent; Dexter was the only one who wasn’t very productive for the first hour. Another slow down for that day was an issue with Google Drive being inaccessible at our school, so we couldn’t access our code in txt form without copying and pasting it on Dexter’s phone, from JT’s google drive, and then pasting it into a dropbox file that JT could access on the computer.

Aidan successfully designed a 6‐bar linkage with a 35‐long main link by moving the entire tower of the robot back one unit, this gave us enough room in front of the full length linkage to build our intake mechanism, once Aidan finished designing the linkage, Dexter proceeded to duplicate the other side and began nylocking it.

Dexter wasn’t able to finish building the entire linkage, because Aidan’s dad started trying to attach optical shaft encoders to the wheels which prevented Dexter from easily screwing in the nylocks on the robot due to its twitching from work being done on it. Luckily though, Dexter will be able to finish building the linkage on Monday.




After designing the intake, Aidan began planning and prototyping a mildly complex pneumatic big ball launcher/hook mechanism. See images below for a more detailed visual of how it works, but basically it works via a rotating c‐channel assembly powered by pneumatics, then another piece swings out more using a sprocket‐chain system, all of this within our relatively small intake basket/trough.

So far this season, we haven’t been able to construct very many interesting mechanisms. It has mostly been based around rather simple drive base, tower, arm, and intake solutions. With the only major source of interesting mechanisms coming from the intake, which is still rather simple and boring for innovation. Aidan, the main team designer is very excited about the prospect of designing a rather innovative mechanism on our robot – both the hanging and launching mechanisms.

JT worked on programming the entire time, minus the little issue at the beginning with Google Drive. He and his friend worked very well together and got the gyroscope working and tested very quickly, but as the day progressed, he tried using a “for” loop in the program to get the autonomous working better, but that work ended up messing with what he had already accomplished.

We hope that Max will come back to work with JT, not only is he a cool person, he also seems to know quite a bit about programming which helps motivate JT to work more. As far as the program went, JT seems to understand the gyro which is good, but the issues that cropped up with the “for” loops he was working on hindered his progress towards a fully functioning autonomous program for the robot.

Moving Forward… 1. JT will continue working on the code for the gyroscope so that he can be ready by next

week or the end of this week to program an autonomous and programming skills routine.

2. The current setup for the launcher/hook that Aidan is working on seems promising, but it’s so finicky that the possibility of it working is rather low.

a. As such, there’s the possibility that the hook may be changed so that it simply acts as a hook and not a dual hook/launcher.

b. The main thing we want is a hook that extends about 8 inches above the rear of the intake trough when the arm is fully raised up.

3. Once the hook is done, or before it is finished, Aidan will work on designing a hang‐lock mechanism using a gear that will latch into the linkage gears and stop them from rotating.

4. Dexter will, like he has been doing, continue working hard on getting the notebook in tip‐top shape.




Team Reflections Dexter “I’m really glad we got to work on Saturday, even with my art competition that I was at earlier in the day. The 6‐bar looks like it should work well; we just need to get it done and tested, which I can do if no one gets in each other’s way.” Aidan “Today was really productive, and the linkage looks like it’ll work, aside from that, the hook is coming along well, and it’s definitely an interesting design that I’d like to pursue, but the design is so compact that some aspects might not work with each other.” JT “I’m really happy about the program, Max was a big help on Saturday, but some of the problems that came up later on were stupid and I want to figure out how to improve the program as soon as I can.”

Here is a view of the newly iterated linkage, using a 35‐long main link. This linkage can reach nearly 30” in the air (seen further back). See the closer side of the linkage for a more detailed sight of the construction of the current iteration.




TASKS REFLECTIONS

Early on in the meeting, Dexter completed working on the linkage, which simply consisted of screwing in a couple of nylocks on 1.5” screws.

The 6‐bar we decided on looks like it’ll work fairly well, the height it reaches is more than enough to reach the tube, but still, when it’s down all the way, it gets pretty close to the size restraint – barely more than 1” of room in front of the robot.

After finishing the linkage, Dexter repositioned the battery holder since it is attached to the tower, and moving the tower back made the battery holder stick out from the back of the robot. All he did really was just stick it on the other supporting L‐channel further inside the robot.

The new location of the battery holder basically functions the exact same as the old one, just a little more difficult to get the battery out, which technically means it’ll hold the battery better than the last one.

Once Aidan got to the meeting, he began fiddling with the hook design, and quickly decided that the current design – using a sprocket and chain with a double flipping mechanism was too finicky for our design and wouldn’t be that trustworthy in competition. So he changed up the design a fair amount, so it’s a simple piston actuated hook that can flip up through the intake mechanism. The bonus about this design is that it’s simple and gets the job done, for hanging. But the downside is that it isn’t very effective for launching a large ball, which we have decided to not do for the time being.

The design change, while it isn’t a good step forward for our overall design plan, it’ll help us move towards hanging much faster, since a simple rotating arm that is piston powered is much easier to build than the crazy multi‐rotating mechanism Aidan was building before. Hopefully, as we progress towards a hanging robot, we don’t get “hung” up on this rather simple mechanism. Tomorrow, we will probably start working more on the lock rather than the hook since that’s more difficult to construct than a simple piston actuated hook mechanism.

Team Reflections Dexter “I’m a little bummed that our robot probably won’t have the launching capability like we had hoped, but I’m glad we made the decision to just focus on hanging, which is a huge point getter and a good attention‐getter for South Texas alliances. Aidan “I wasn’t expecting the chain bar to operate the way it did, taking away the launcher is fine, because hanging can score more points and requires less parts than a launcher.”




Here is the linkage in the full down position, this linkage design uses a 35‐long aluminum c‐channel for the main link that spans from the top axle on the robot all the way to the ground. By changing the linkage

Here is the intake basket with the current hook iteration visible in the middle of the

basket. With a piston powering system, the hook will flip up and be tall enough to hook on the hang bar.

Here is a view of the hook mechanism rotated up, in the hanging position. When the arm is raised, this hook is tall enough to reach the hang bar. In addition, during driver control, this hook can be used to knock big balls off the 12” barrier without having to use the arm.




Pneumatics Price Sheet

Tank

o Reservoir ‐ Reservoir, 1‐1/2" X 4", w 1/8"NPT & M5 port ‐ US14227‐S0400

Plccenter ($21.20 ea.)

Piston

o Cylinder, Bi‐directional ‐ Dbl Acting Cylinder 10mm Bore ‐ NCJ2D10‐200

Plccenter ($15.60 ea.)

Solenoid Fitting

o Fitting for Valves ‐ Fitting 4mm Tubing x M3 Thread ‐ KJS04‐M3

Plccenter ($2.79 ea)

Tank Fitting

o Fitting for Reservoir ‐ 1/8 X 4mm Male Connector To Reservoir ‐ KQ2H03‐34S

Plccenter ($1.05 ea.) todaycomponents ($1.41 ea)

Piston Fitting

o M5 Male Connector for Cylinders ‐ KQ2S04‐M5

Amazon ($2.19 ea.) todaycomponents ($2.19 ea.)

Tubing

o Can buy from VEX (5’ for $5)

T‐fitting

o "T" Fitting ‐ "T" Fitting for Valves ‐ KQ2T04‐00

Plccenter ($21 for 10), todaycomponents ($2.89 ea.)

Tire Pump fitting

o Tire Pump Fitting ‐ Shraeder Valve With 4mm Tube Fittings ‐ 8090410075




Tuesday 2‐11‐14

TASKS REFLECTIONS

JT continued working on the programming. He and Doug, our mentor, worked on the “for” loops that JT was trying out on Saturday. Together, they seemed to figure out some errors that arose during testing, but at the end of the day, couldn’t come up with a final solution to this programming dilemma. Hopefully by the end of the week, he’ll figure out the gyroscope code.

JT got the idea to use “for” loops with Max on Friday; he’s hoping that these “for” loops will assist the robot in turning, mostly easing in and out of the turn, which can assist with turn accuracy. Ultimately, it’s not imperative that he finish by Friday of this week, but it would be incredibly useful to get a fully functional autonomous in the works or finished by Saturday since we have a scrimmage planned with Pastoral Invasion (4252A) and two Anderson High School teams (2158 M and W).

Aidan put off working on the hanging hook in favor of working on the hang lock, since that mechanism is a bit more complex than the hook itself. He finished the base lock mechanism, but hasn’t figured out a way to implement the pistons themselves (since this mechanism will be piston actuated, after all). For a description of the mechanism, look at the image attached below…

This mechanism looks like it will work well, it’s a relatively simple idea that has already been implemented by Anderson’s M‐team and tested in competition a couple times. The only current problem that has arisen with the design is that the piston must be placed behind the tower and clear the 84‐tooth gear that powers the arm, meaning it has to angle outwards at the bottom of the piston shaft and ultimately extend past the furthest point on the back of the robot, something we desperately want to avoid.

Dexter worked on the notebook pages from the weekend and Monday, getting pictures and a thorough write‐up finished. Besides his work on the notebook, he also put an optical shaft encoder on the rear wheel of the robot, but the current fit of the encoder is so tight that it adds friction to the rotation of the wheel, something we don’t want to have on the drive.

Optical shaft encoders are an important addition to the robot, because they allow us to figure out how far the wheels move via the number of rotations the wheels make, making autonomous programming much easier. But, if the encoders don’t fit anywhere easily, we will probably just exclude them from the final design and continue using time based movements.




Pictured above is the prototype for our hang lock. The basic design implements 2 1x4’s on each side of the metal pinion and 2 45° gussets that theoretically get attached to the piston. The

metal pinion is locked in place by a lock plate. In theory, this mechanism rotates around the top gearbox pinion’s axle, and the locked pinion will hold the 84‐tooth gears in place, locking the arm at any position – low or high hanging – the benefit of this is that it can be disengaged.

Team Reflections Dexter “Today was a good day, it’s nice to see everyone working hard on their separate projects, I’m most hopeful about getting the hang lock finished, but worried about the issue of the piston extending too far back outside of the robot’s current boundary.”



Recorded By: Dexter Snacks: cheese crackers Page:

Wednesday (2‐12‐2014)

TASKS REFLECTIONS

Before Aidan and JT arrived, Dexter completed the notebook for the previous day (2‐11‐14) and then he worked on the hang lock mechanism a little. He figured out that the piston can simply be mounted offset to the lock mechanism itself, and the bottom hole of the piston lines up perfectly with a top corner screw hole on the drive base.

When Dexter found out about the super easy piston mounting solution, he was very happy, because it basically means that the lock can get finished today, or at least much sooner than expected. Hopefully, this new ‘discovery’ can help progress our robot towards a finished product by at least Saturday, if not by then, finished on Saturday, for a full week of practice.

Aidan worked on fully attaching the piston, but there were several problems that popped up during this process, one that the robot was being commandeered by JT for programming almost the entire time, the other problem was Aidan’s dad robot, a little side project he worked on earlier in the season, which was using the last metal pinion we own.

Marshall, JT’s friend was nice enough to start disassembling Doug’s robot, so we could get the pinion from his and use it in ours. Aidan finished the day by building the other lock mechanism for the other side of the robot, but didn’t have enough time to fully attach the mechanism to the robot. Tomorrow, Dexter will finish assembling the entire lock mechanism, including attaching the pistons to the lock mechanism.

JT worked with Doug on the “for” loop programming again. For most of the meeting they worked on getting rid of rogue elements in the code left over from past years. Then they started working out the actual ‘for’ loop issue, which started out just being that the robot would go forwards, then backwards, and forwards again instead of forwards, backwards, and turn, which is our current middle zone autonomous.

Even though Doug and JT worked for a long time on the programming issues, neither one of them figured out a solution for the problem. During their testing, the only breakthrough they made was getting the robot to spin in circles for an indefinite amount of time after going forwards and backwards once, instead of the robot going forwards and backwards over and over again. At this point, we want to get the gyro code finished by the State Competition, having it finished by the end of this week isn’t the most important thing.

JT’s friend Marshall was here too, and we put him to work disassembling Doug’s robot to salvage the single metal pinion buried within. He also assisted Aidan by copying the hang hook mechanism.

Having one extra person here sometimes can be useful, because we can have one person programming, notebooking, building, and the 4th person as an extra hand, usually for building.



Recorded By: Dexter Snacks: cheese crackers Page:

Here, you can see the piston’s alignment with the lock mechanism and the drive base, the piston’s rotating bracket gets screwed right into the lock mechanism and the bottom of the piston gets mounted in the rear‐most top hole of the drive base. In the picture, the piston is getting tensioned up, so the piston is fully extended, if the piston was contracted fully, the locked pinion would fit perfectly into the 84‐tooth gear our linkage uses.




Thursday (2‐13‐2014)

TASKS REFLECTIONS

Today, the team continued doing the same thing as always, Dexter on the notebook, JT on programming and Aidan working on robot mechanisms. The entire group didn’t start working until about 4:50 or 5:00, leaving a measly 30 minutes for actual work.

At this point, we’d hope to be finished with the robot, but with the wait time for our pneumatics parts, work on the robot has indefinitely stalled since the only mechanisms left are the intake and pneumatic powered hook, which we can’t make for obvious reasons.

For the last 30 minutes of the meeting, Aidan and JT worked together on figuring out a solution for the intake, one that is very similar to 2158M’s flip down intake. The major aspect we need for the intake now is one that starts flipped up and doesn’t extend past the front of the robot, because that basically defines our size constraint currently.

All of our intakes relied on a system that rotated horizontally then vertically, meaning there was a protruding element from the robot that was used as the vertical rotation point. Now, we need to focus on something that folds up and down then rotates in and out. While this shouldn’t be the most difficult task to accomplish, it’ll be a departure from a design we’ve used at every competition so far. The old design utilized a hinge attached to the linkage and a right angle connector, so the angle piece would rotate in and out, then an axle would be put through the flat side of the angle connector and into a c‐channel that would rotate up and down.

JT worked for a couple minutes on programming the gyroscope code, but didn’t really make any progress on getting the code working or fixing the issues that cropped up in the “for” loops. He ended up just trying to get an intake design working with Aidan.

At this point we’ve decided, even if it’s not an official decision, that we are going to focus on the robot more than the programming, a big reason why JT left the computer in favor of the robot. We just need to get something ready for this weekend since we have planned to “scrimmage” with 4252A, 2158M, and 2158W, or in other words, work on our robots in the same room as each other.

Part of working on the intake included Aidan attaching the intake “basket” to the linkage, which made our robot much more complete looking. Dexter also finished the piston lock earlier in the day.

Having the piston lock finally finished and the intake basket attached allows us to focus on the important issues at hand, like creating a hook and a good intake, one that doesn’t have the typical McCallum Slop.




This is the robot in a semi‐complete form; the inklings of an intake are barely visible on the front of the robot, but hopefully after tomorrow (Friday), there will be some semblance of a

finalized intake on the robot. Our basic gameplan for the intake is to make a 5x20 plate rotate down 180 degrees from its starting position, to act as an extension of the intake basket, but

also as an attachment point for the intake mechanism itself.


Date: 2/14 – 2/16 Start Time: 2/14 (3:30 pm) End Time: 2/16 (6:30 pm)

Recorded By: Dexter Snacks: variety Page:

Friday, Saturday, Sunday (2/14/14 – 2/16/14)

TASKS REFLECTIONS

On Friday and Saturday Aidan and Dexter worked on an intake mechanism that would have the highest storage capability possible, something that has become incredibly important as we move towards a finished mechanism. The design, pictured and described in detail below, was a rather complex one that used many parts, ranging from pillow blocks, about 4 c‐channels of differing sizes, standoffs, 1‐bys, and spacers of all sizes. They finished the intake around 6:00 p.m on Saturday, and took the robot over to Pastoral Invasion’s (4252A) workspace, quickly realizing that the seemingly flawless intake they’d been working on, would not work after all, mostly due to it not fitting within size constraints when in the storage position (folded inside the 18” cube). So, they scrapped the idea and began thinking about a new method for building an intake.

All the time that both Aidan and Dexter spent on the intake was for nothing, unfortunately, but it is good that we found out about the problem before the end of the weekend since we also planned on working all of Sunday. The biggest problem we face going forward with the intake is the storage position, it’s really easy to create something that just extends out in front of the robot and stays there, but creating one that flexes in and out, plus up and down is very difficult, plus adding all of the necessary stops to keep it in the best position for intaking is another challenge. But really, the biggest challenge we face is getting a viable intake to fold into the robot, so that the starting position is within the size constraint. With our linkage being full length, we’ve had to really do some thinking about the intake, more so than we have had to in the past.

On Sunday, Dexter and Aidan continued working on the intake, this time trying to sort out a new strategy for the intake design. Pastoral uses a rather simple design that only rotates in and out, so the starting position is outside or inside the arm, and within the 18” size constraint. As Aidan worked on this design, he realized that with the way our robot is constructed, this sort of folding method would not work, because the rollers can’t fit inside the intake, and if they folded out, they would stick out the sides of the robot, which again isn’t an option for us. So they then began working on a design that is similar to Pastoral’s, but adds the up‐down rotation for better storage (pictured and described

We need to steer ourselves towards making a simple intake, then perfect that design as the week progresses towards the South Texas Regional. The current design that Aidan and Dexter are working on seems to be the b viable one so far, but it’ll be cutting it close to the size constraint. There are two options for the intake, the first is the design we’ve been working on for a long time, motor facing down, powering two gears, where the second gear powers the rollers, the second option (the one that seems to be getting used more and more) is where the motor faces up and directly powers the rollers on top of the c‐channel. The motor on bottom seems the best, currently for space saving reasons.




below).

On Saturday, Aidan, Dexter, and Doug set up a full 12x12 foot practice field in our room at school that we will be able to practice on once the robot is finished. It took about 2 hours to setup, which took a decent chunk out of our available work time, but it’s definitely worth the time input, because being able to use this field for practice and programming skills will be invaluable to us at the South Texas Regional, which is fast approaching.

Once the intake is finished, Dexter will be going into the room to practice as much as possible, during school lunch, during his off‐periods (2 of them to be exact) and as much as possible after school, if JT isn’t doing Programming Skills. We are also considering skipping some of our less important classes to work on finishing the robot, practicing, and programming. But, like I said just before this, the intake is the only thing holding us back from doing those things, including the pneumatic hook, so everything has halted currently.

On Sunday, JT and Max worked on programming the robot, since they didn’t have the most up‐to‐date program, they used the one that we had on the robot from the Austin Competition (named Comp Temp Stubbier 1.7… yep). The upside to using this program is that it doesn’t utilize the ‘for’ loops that seemed to be plaguing JT for the entirety of last week. As soon as he programmed in the gyroscope code like he had done originally, it worked perfectly, with a nicely programmed turn. For the rest of the day, they worked a little bit on perfecting the middle zone autonomous, just making sure the proper pauses were used, and the proper accelerations in and out of the turns and straights. Based on their successes on Sunday, it seems like JT will be able to ‘easily’ program a programming skills routine. Towards the end of Sunday, the two of them also worked on a diagram of where the robot will go, where it will score, which balls it will pick up, etc… See the attached image below for a detailed description of their plan.

At this point, the primary goal is to get a solid autonomous program for the regular competition working, hopefully our middle zone autonomous will score the preload bucky ball in the tube and knock the large balls into the high zone. As for the low zone autonomous, we’re not really sure at this point what to do, we’ll either hang in autonomous, since our mechanism allows us to disengage the hang lock without damaging any parts of the robot, but we may also opt for a simpler autonomous that knocks both large balls and bucky balls into the middle zone, or even one of the large balls into the high zone. It was also really good on Max and JT’s part to diagram their programming skills routine, and write the pseudo‐code for it too, all in all, for programming the team is back on track to getting a finished product by this coming Friday.




Here’s the field set up in the back of the room. There’s a lot less table space, but the current arrangement of the tables is actually really nice (you can see our table in the bottom left corner of the picture) because before, the tables were doubled up, so no more than one person could work on the robot, whereas now, with a single‐wide table, even 3 people can easily work on the robot without interfering too much in each other’s work. Also, with the

field, we’ll be able to easily practice driving the robot, testing our intake mechanism ideas, and working on our programming.

Here are two different views of the intake we spent Friday and Saturday designing, then scrapped. The c‐channel highlighted by a blue line (barely visible) is one of the terminating links of our linkage, and a 15‐long c‐channel is stood off from that link. Towards the top of this link, highlighted by the red circle, are two pillow blocks that act as the up‐down pivot point for the intake. The pillow blocks are directly connected to a 10‐long c‐channel that flips from being parallel to the ground in the up position to being perpendicular to the ground in the down and ready

position (as seen in the right‐hand image). This 10‐long c‐channel has a hinge on it, highlighted by the green circle, which acts as the side‐to‐side pivot, we’ve used hinges for all of our side‐to‐side pivots so far. Attached the hinge is the intake mechanism itself, which is passed over from our last iteration using the 45 degree gusset. Highlighted by the white box is the motor, gear, roller system, basically the motor powers two plastic pinion gears, the first directly driven by the motor and the second gear attached to the roller axle.




Our current plan for the programming skills routine is to start in the low score zone, start with the preload, and pick up the two bucky balls that are against the wall. After gathering these three bucky balls, we’ll cross over the bump and knock off the first big ball from the barrier, make a turn, and knock the second one off. After knocking both large balls off of the 12”

barrier, the robot will drive up to the tube and stash the 3 bucky balls in the tube. Theoretically, we would then cross back over the bump and pick up one of the other color’s preload buckys, and the 2 against the wall in the low score zone, knock over the two large balls, and then hang. However, Dexter watched 2158M’s programming skills routine and

realized that it is really only possible to do about half of what we planned. It is possible that we could do the first half of the routine, go back to the starting tile, reposition and knock over the other 2 large balls off of the 12” barrier. Overall, the goal is to score 3 bucky balls in the tube, 4 large balls in the high zone, and high hang with a large ball, getting us a score of at

least 55 points, plus if we can knock the bucky balls off of the bump, that can score us an extra 3‐6 points depending where they roll.


Date: 2/17/14 Start Time: 4:30pm End Time: 7:00pm

Recorded By: Dexter Snacks: apples Page:

Monday (2‐17‐14)

TASKS REFLECTIONS

Dexter started working on robotics related things during his off period, but the robot parts weren’t at school yet, because we worked at Aidan’s house over the weekend. So instead of working on the robot, which he had planned to, he started working on the notebook from the weekend meets.

It would have been nice to have the robot and all of the parts during Dexter’s off period, we need all the time we can get to try and finish the robot as soon as possible, so we can practice and program the robot before the South Texas Regional. But at the same time, it’s important that Dexter keep up with the notebook’s quality over the next week, to broaden our chances for awards.

When the meeting officially began, Dexter worked on the intake for the entire 3 hour long meeting, getting to the point of making something that seems mostly viable. It both meets the requirement of folding up within the robot’s dimensions and folds out to operate as a fairly decent intake. The basic concept of it is that a 5‐long rotates on a 2 inch screw inside the outer bar of the linkage, then the intake rotates horizontally off of the 5‐long. There are a few things that need to be perfected to make sure the intake works properly: 1. Make sure the intake slopes downward

very slightly, this seems to work better.2. Implement a horizontal rotation stop

that prevents inward rotation past a certain point.

3. Make sure the intake is supported very well in both the vertical and horizontal direction (and make sure the vertical and horizontal stops are high functioning).

4. Get a good separation – about 1‐3 inches – between the two bucky ball rollers.

a. The larger the separation, the higher inward tension required.

5. Intakes big balls ‐ IMPORTANT

The intake design that Dexter created seems like it should work fairly well. Not only does this design have a very wide opening (to assist with large ball intaking) but it also seems like it will be fairly modifiable. Unfortunately, for the purposes of this notebook, Dexter went through many, many small iterations to get something that seemed to be the most viable option for the intake, and it was basically impossible to take pictures of each iteration of the intake. Hopefully as Dexter continues working on the intake, he can perfect each aspect of a good intake that he listed in the tasks cell.




Aidan worked on building the pneumatic hook mechanism, the basic design is rather simple: the hook starts off in the down position, basically acting as a part of the intake basket, then a piston extends and raises up the hook (meaning we can’t have anything in the intake when the hook gets raised).

The first iteration of the hook that Aidan made flips forward, so the actual hook part of the hook can be behind the hook arm. However, one major thing that needs to be considered is leaving the right amount of space for the large ball to fit in between the rollers and the hook arm. Also, like the intake, the hook continues to go through many iterations, so any pictures of it in the notebook are for the general concept of what it does, a final picture will come closer to the day of the competition, the same goes for the intake.

As usual, JT continued working on the programming of the robot, primarily working on the turn amount with the gyroscope, now that he figured out how it worked. He also got the pneumatics programmed, which is super easy, even though we’re not currently using the pneumatics.

At this point, programming is slowly taking a back seat to the actual process of finishing the robot. While JT is making good progress on figuring out the programming of certain parts of the robot, the team really needs to make progress on the actual building aspect of the robot. In fact, Dexter has had to start squeezing in notebook writing into other periods of the school day, and even writing them at home.

Moving Forward…

Dexter needs to finish building the other side of the intake and tweak it.

Aidan needs to continue working on the pneumatic hook so it gets to the proper height and allows a large ball to sit between it and the intake rollers.

Once those two things are finished, Dexter will start practicing driving and testing the various mechanisms that have been built over the past couple of weeks.

JT will continue working on the programming, mostly making sure every sensor on the robot is implemented and ready to be utilized in a programming skills routine and multiple autonomous routines.

Once everything is finished being tweaked, Dexter needs to PRACTICE!!!




This is our ‘drive’ function (for autonomous). It’s written so that when we input the (max) motor speed and the distance (in inches), it calculates how many pulses the shaft encoder needs to register before stopping the function. It also accelerates in three stages to prevent

tipping during the autonomous period (see p. for related math).



Recorded By: Dexter Snacks: HEB Chz‐Squared Page:

Tuesday (2‐18‐14)

TASKS REFLECTIONS

Today, Dexter decided it would be the best use of his time to devote the entirety of his work day to the intake. By skipping his 3rd period class, he was able to work through the 3rd and 4th period of the day, plus after school, totaling 6 hours of work. By the end of the school day itself, he had a legitimate concept for how the intake would work, and a semi‐functioning prototype. Throughout the remaining 3 hours of the meeting, Dexter added the inward stops, perfected the downward stop, added tension, and built the other side of the intake. The system itself is relatively simple, and is described and pictured below. All that needs to be done at this point is getting the intake basket/hook attached to the linkage, testing the intake and making any necessary tweaks.

The intake Dexter made today seems to be the most promising one yet for a few reasons: 1. By having the intake roller arms

angled inwards, it prevents them from getting pulled outwards ‐ which causes the balls being kept inside to fall out.

2. The rotation points of the intake arms are so far apart that the process of intaking a large ball is nearly unobstructed.

3. The mechanism itself is relatively simple and structurally rigid, with the added bonus of being slightly modifiable.

4. Lastly, the intake roller arms are angled fairly equally and neither one droops significantly more than the other, like previous intake designs we’ve had.

JT came in during school to work along with Dexter on the robot, mostly trying to program the robot, but was barred from making progress, because the computers were blocked from internet access (from the class period before), we didn’t have administrative privileges to access certain files, and to top it off, the remote and cortex wouldn’t pair no matter what we tried, so JT gave up on programming until after school.

After school, JT was able to fix the connection issue by updating RobotC to a newer version, then from that point on, he worked on getting the robot’s optical shaft encoders programmed. The biggest difficulty we had with them was figuring out what unit of measurement they use, as it

Early in the day, the issue with the connection between the controller was slightly worrying, no matter what JT and Dexter tried, nothing would make the connection work. But, as always, it turned out to be an issue with RobotC and by updating it, everything worked perfectly, even though everything was working the day before.

As for the optical shaft encoders, JT spent a good deal of time trying to figure out what kind of measurements the optical shaft encoder took, and how to convert said measurements into inches travelled, which would make programming an autonomous as easy as just measuring the field. Unfortunately this didn’t get done, because the conversion JT found (90 ticks per rotation) was for easyC, and we use RobotC




turns out from Dexter’s research after the fact that we were using EasyC units. But JT got along fine with the slightly broken state of the programming, simply guessing and checking the amount the wheel would rotate by running the autonomous program over and over again.

for all of our programming, which Dexter found uses a different measurement system, 360 ticks in increments of 2, so hopefully this new discovery will allow JT to quickly convert sensor ticks into inches travelled on the floor.

Aidan continued working on the pneumatic hook, because the way he made it yesterday (rotating up and forward towards the front of the robot) interfered directly in the space where a big ball would sit in the intake. So today, he worked on creating a mechanism that would rotate backwards, with the point of rotation at the end of the intake basket, giving (hopefully) ample room for the large ball.

Like the intake, Aidan’s hook went through several small iterations, each one proving unsuccessful until a promising design turned up. The decided upon hook design is pictured and described below. The only foreseeable problem with the current design is that the actual hook will have to be mounted beneath the intake, and when flipped up, will face forward, meaning we will have to drive forward towards the hang bar in order to hang, something that probably isn’t possible.

Pictured above is our current intake design. The basic concept of it is similar to every intake we’ve had previously, two bucky ball rollers, and two large ball rollers on either side. The motor power system is also the exact same design as the previous intake design from the

Austin Toss Up Competition. This time however, there is a 5‐long c‐channel that rotates up and down on the outer terminating bar of our linkage (visible to the right). Then, rotating on the

end of that 5‐long c‐channel is the intake arm itself which is sharply angled inwards. The angle at which the intake rests can be seen more clearly in the right image. In addition, there is a 2‐long c‐channel attached to the 5‐long that acts as an inward stop for the intake arm ‐ there is an ⅛” white spacer providing the proper stop angle. Plus, another 5‐long c‐channel acts as the

vertical stop ‐ this is barely visible in the right image.




Here are two images of the current intake basket/hook mechanism. The rotation of the hook is powered by two pneumatic pistons; the pistons are mounted near the base of the intake and retract to raise the hook. The range of motion we got is thanks to the pillow blocks mounted on standoffs that are on the base of the hook. At this point, the only thing that needs to be done is to create the hooking part of the hook itself, which is really easy, then test it, and see if it hooks onto the bar. The downside to this design is that the hook needs to be mounted underneath the intake, meaning the robot will need to drive forward into the hanging bar, generally

something that isn’t possible.




This is our autonomous program. It has been overhauled to be streamlined (it’s about ¼ the size of the old autonomous program). Additionally, the autonomous recognizes (based on

jumpers) whether it is in the no‐ or low‐scoring zone, as well as weather it’s on the blue or red side of the game field. Programming our autonomous has assisted JT in our final goal of writing

a programming skills routine efficiently.



Recorded By: Dexter Snacks: food Page:

Wednesday (2‐19‐2014)

TASKS REFLECTIONS

Today, Dexter worked on putting the finishing touches on the robot, mostly attaching the intake basket/hook to the linkage. He, once again, decided to skip a class in order to work on the robot, which really paid off, because he was able to finish and practice driving before the after school meeting began. The finished robot with the intake basket attached can be seen below. Changes that need to be made include: 1. Lower the bucky rollers slightly. 2. Raise the Large ball rollers slightly. 3. Incline the intake basket more (to help

with stashing of the bucky balls). 4. Fiddle with the tension to keep the

intake down, and not spring back inwards so much.

5. Rubber band tension mounts (two of them run the risk of hooking on the scoring tube, which happened and flipped our robot on its back).

There were a couple things that Dexter realized about the robot. 1. Intaking the first two bucky balls is

pretty easy, but the third doesn’t seem to want to go into the intake.

2. Large ball intaking is very good, could be improved a little since it requires being up against the wall to intake one. However, outaking the large ball isn’t great, it requires some robot twitching in order to work properly.

3. The biggest problem is that the arm stabilization program hasn’t been updated in a while, meaning when the arm gets raised to a certain point, it flips out and one side drops down and the other locks up in place. Plus, sometimes the arm will just stop working.

Dexter also attached a very crude arm stop which was simply a 1” screw going through the bottom hole of the chassis, attached with a nylock, and it does its job just fine.

This stop might be a little too high, because it runs the risk of pushing the end of the linkage out of dimension, and like always, dimensions are proving to be very tight.

Later on in the school day, Dexter took off a small 1x5 spacer that was holding the 5‐long c‐channel on the intake up, it lowered the intake a fairly large amount, but also angled everything forward a bit, meaning the large ball rollers would make contact with the large balls before the bucky rollers. After making this very minor modification, the intake worked magnificently for large balls, and only so‐so for the bucky balls, but the bucky intaking can be adjusted by raising the rollers, and increasing the space between bucky rollers very easily.

The current configuration of the intake (as of 7:00 pm today) seems incredibly promising, with a little tweaking it can be really good at picking up both the bucky balls and the large balls. The thing that needs the most improvement is the bucky intake, which can be easily fixed by merely widening the space between the rollers and increasing the bucky roller’s height above the ground.




One issue that arose, but was quickly fixed was when Dexter tested the robot’s hang, which didn’t work at the time because of weird arm programming, but the person who Dexter volunteered to lower the arm continued to lower the arm when the robot was on the ground, ending up in a snapped link, but we easily repaired the damage.

It’s kind of surprising how easily our 7:1 gearbox can snap an aluminum c‐channel, but even more surprising that our physical arm float (which is literally just a screw through a nylock on the drive base) doesn’t get effected by something with that much pressure acting on it.

Yesterday, Aidan made another hook mechanism that flipped backwards, but it was agree upon that that would not be the best option for the hook, so he built a front flipping hook that is very long, reaches the hook with ease when the arm is fully lifted, and leaves enough room between it and the rollers that a large ball can fit within them. This current hook seems like the most viable option, having the qualities of being strong, rather lightweight, and highly functional.

While we did run out of time today to do any sort of testing on the hook and the lock, the hook seems incredibly promising, only requiring some VEX legal rope to constrict its movement. However, the hook does look very promising and should work as we intended.

Today, JT finished implementing the optical shaft encoders into our robot’s program, which he then used to program a middle zone autonomous. Currently, since we had bad luck with the LCD programming display at worlds, we are using jumpers to switch between programs, one for each zone, and one variation of each of those 2 for different colors of the field. Using optical shaft encoders will prove invaluable to our programing efficiency, because now JT will be able to simply measure how far he needs to drive on the field, how much the robot needs to turn in degrees, and just plug that information into the robot’s code.

This iteration of the robot utilizes the greatest number of sensors of any previous iteration of the robot thus far. Currently, we use one optical shaft encoder on the drive, a gyroscope (which we’ve had on the robot for a long time, but never actually used), and potentiometers, all of which are actually being used. The gyroscope and optical shaft encoder will be incredibly useful for making the programming skills routine.

At the end of the meeting, Aidan plumbed the pneumatics completely (see diagram after 2/20 entry). He decided to connect the cylinders so they act like single actions instead of double actions, once he finished hooking everything up, he tried filling the system, but there was a leak somewhere, which he’ll try to fix tomorrow at some point.

The plumbing went smoothly, nothing majorly good or bad happened, as nothing got ruined, there were no snags in the assembly, and it didn’t really work, so nothing great happened.




Here is the fully completed robot at this point, with the intake basket mounted at a fairly low angle in relation to the ground. In this picture you can also easily see the inward angle of the intake roller arms. At this point, the robot seems fairly high functioning, but still, some small

changes have to be made to get the robot up to its highest functional capability. The other thing, besides the intake, that needs to be worked on is the hanging mechanisms, mostly the hook itself. Dexter was thinking it might just be easiest to make a floppy hook that operates on a hinge, like our M‐team is working on, and a design that the infamous 2587Z

(DiscoBots) used. The main problem with this sort of design is that the robot can only go under the 12” barrier in one direction, usually forward since the hook should be facing backwards, but driving forwards to go under the bar shouldn’t be a problem, just needs some getting used to.




The first two sections of this snapshot are toggles for our pneumatic pistons. It’s written as a toggle (instead of just setting SensorValue = vexRT) so that the cortex saves the value, and the robot does not fall when driver control ends. The third section is the arm‐stabilization code. In this section, the cortex first converts the raw potentiometer values into a percent scale for

easier comparison. It then modifies the speed of each arm as it raises and lowers to keep them equal. When not in use, the cortex saves the value of each arm, averages them, and attempts

to hold each arm to the saved position with code that simulates a spring constant.



Recorded By: Dexter Snacks: pretzels Page:

Thursday (2‐20‐2014)

TASKS REFLECTIONS

In the morning, Aidan fixed any plumbing issues we had with our pneumatics tubing and fittings, yesterday we found that there was a leak in the system, most likely from a bad fitting or a loose tube. After fixing the tubing, he was able to pump up the tank and test the hook and gear lock, which both work properly.

By fixing the leak we had yesterday early in the morning (a relatively small problem in comparison to some of the others we will have to conquer tomorrow) we can now work towards tweaking the hang. Aidan’s and the other team members’ ability to work during their free time really exhibits our team’s readiness to devote as much time as they can to the robot, we would stay at school until midnight if we could, but sadly we cannot.

Today, the primary thing Dexter worked on was configuring the intake to get it working at max capability. The big two things he did was removing a spacer between the bucky roller and the intake arm, and adding spacers in between the parallel linkage bars and the outer terminating bar. What this did was effectively separate the entire intake by about 1.5 inches, and raise the bucky roller by about ¾ of an inch. Raising the intake has seemed to help other teams, and separating the rollers was just something that needed to be done regardless. After making these changes, Dexter tested the intake with mild success, and found that lowering the intake by a small amount could help, but more downward tension would make a big improvement too. Early in the meeting, he wasn’t able to do a full test run of the robot, because our arm stabilization program needed to be recalibrated after all of our work these past weeks.

With only a few minor changes, this intake can work very well, better than most of the intakes we’ve had on the robot previously. It’s really nice to be able to have the intake done a couple days before the competition starts, because it means that, for the next couple of days, we are able to test and configure the intake to make it work as good as possible. Dexter was a little put out that he couldn’t drive the robot around like normal due to the arm stabilization de‐calibration, so instead he worked on pre‐competition preparation like compiling all of the entries from the past month into the notebook. As far as the notebook goes, there’s definitely room for improvement in the future (say if we were to qualify for the World Championship, magically), but for now he thinks it’s fairly complete. Besides the notebook, at this point Dexter needs to do as much practicing as he can, squeezing it into whatever free time he has at school.

During school, Aidan worked on recalibrating the arm stabilization program, more specifically, the potentiometers that measure the rotation of the arm. He wasn’t

While the arm stabilization is a seemingly easy to understand concept, programming‐wise it is quite complex. Aidan is the one to be credited with the arm stabilization code,




able to finish during the 30 or so minutes he had between working on the pneumatic hook and going to his AP Stats class. However, right away after school, he was able to get the program working, realizing that at some point one of the pots got flipped around so it was displaying negative values (see math for arm stab. programming on following page). By getting the arm working, the team was then able to fully test all of the mechanisms on the robot: hanging and intaking, mostly.

something that not many teams have at this point, but something that has become incredibly useful to Dexter when operating the robot. The program simply sticks the arm where it is when motor power gets cut by applying a small amount of motor power to keep the arm up (noted by a high pitched motor noise) but in addition to this, the program increases motor power as more pressure is applied to the arm – meaning it acts like a very rigid spring.

After getting the arm stabilization program was recalibrated, Dexter and Aidan tested the robot, mostly the intake and the hanging.

The hanging, tested first, works… And it might work with a large ball, but we aren’t exactly sure right now. If the batteries are fully charged (they will be tomorrow, for final testing of everything) the robot will lift itself up with a 4 motor 7:1 lift. Both of the piston mechanisms: the hook and the gear lock both engage properly, using the button presses that Dexter requested early on, for ease of use. Both mechanisms operate on toggles, so he simply has to press a button to prop up the hook, and press another to lock the arm in place. The hook swung too far forward at first, but this was easily fixed by adding pieces of nylon rope to constrict its movement forward. The rope also takes most of the load off of the piston itself.

The intake, on the other hand, needs to be configured more, the intake rollers get pushed up by the bucky balls instead of staying down, in the optimal intaking position, which warrants the use of more down tension, an easy thing to change. In addition, Aidan added side rails to the intake basket which will help guide the balls

The intake, in its current iteration, like I’ve said before, seems good, but can always use improvement. The biggest problem with it right now is that when it starts intaking the 3rd bucky ball, one side of the intake rollers starts to lift up, and the balls either roll out, pile up weirdly above the basket, or the 3rd ball just goes under the intake roller and away from the robot entirely. This could be the result of multiple things: the basket being at too steep of an angle and the rollers aren’t supplying enough power to get the bucky ball up the ramp, that there isn’t enough down tension on the intake, or that the bucky ball rollers aren’t low enough. Dexter is leaning towards the down tension idea, since he is the one that built the intake and didn’t really pay too close attention to the actual tensioning of the intake, whereas Aidan is leaning towards the issue being the height of the rollers. Tomorrow, Dexter will fiddle with both of these ideas, seeing which improves the intake most.

As for the hanging, everything seems good now that the nylon rope has been added, all that needs to happen is a final test with fully charged batteries (to simulate an actual match condition) and to see how we can pick up a large ball and hold it while we




up the intake, as well as keep them in while the robot drives around.

hang.

At the end of the meeting, JT began working on the programming skills routine, finally. By working continuously on the program throughout this and last week, and creating functions like drive, turn, turn, and take that utilize the sensors on our robot, he was able to very quickly start on the skills code on the robot. He measured out all of the distances via tape measure and used 45 degree angle turns throughout the entire run, to minimize the need for actual angle calculations. He got about half of our planned routine coded (see pg. for a diagram of our planned routine). But, as was expected, the program worked perfectly for the first two steps, drive forward and intake, but otherwise, nothing worked. The bump has proven to be a mortal enemy for programming, using the optical shaft encoder for that section is almost worthless because the wheels spin out, giving irregular values, plus the gyroscope only seemed to work one time during our various tests. Hopefully tomorrow, he will be able to sort out some of the difficulties he was having while programming today, but we had to leave before any major progress was made.

Once JT figures out the bump situation (possibly using time based travel for bump crossing) the program should be smooth sailing from there on out. Besides the bump, there is also the problem with the gyroscope that seems to crop up and go away depending on what day of the week it is. Sometimes, it just makes the robot spin in circles, other times it works flawlessly, none of us were able to figure out what exactly the problem was with it, but it could possibly be due to it storing some rogue value that shouldn’t exist. JT will continue working tomorrow during school hours to get our programming skills routine functioning at its max potential. We’re hoping to surpass 50 points, but we’re not completely sure how certain it is that we will get that kind of score with our current predicament, and our limited amount of time. The plan we referenced before should theoretically score about 70 points, but it’s doubtful that it’s possible to do that within 1 minute.




Here are 3 images of our finished robot, the left image being of the robot with the arm and hook down, the usual driving position. The intake configuration can be seen in this image, sharply angled in, with a slight downward tilt. The bottom left image shows our robot in the fully extended position, with the hook extended and latched onto the bar as well. Our tactic for hanging (since all of the pistons are plumbed to be single action pistons minus the spring) is that Dexter will raise the arm and extend the hook. Once the hook is above the bar, Dexter will disengage pneumatics on the hook and the down‐tensioned (with rubber bands) hook will lock onto the bar, Dexter will lower the arm, lifting the robot until it can’t lift anymore, and engage the gear lock. The bottom right photo is a close up of the hook/intake area of the robot. The piston contraption is hardly visible, but detailed pictures of our robot’s mechanisms will follow this entry in the notebook.




Here is a screenshot of the current programming skills routine. JT was able to define functions for all of the tasks the robot is required to do, such as drive, turn, take, and lift. By measuring out the distances he

needed to travel on the field, in inches, and exclusively using 45 degree increment turns, he was able to write

out about half of the pseudo‐code for the skills routine, and then easily create the program itself.

Today, he didn’t really make much progress on getting the programming skills routine functional, but it seems promising, and troubleshooting should be

easy, as long as all of the sensors are fully functioning.


Date: 2‐21‐2014 Start Time: 9:00 am End Time: 7:00 pm


Friday (2‐21‐2014)

TASKS REFLECTIONS

Today, Aidan and Dexter continued making small modifications to the intake, trying to get it working as well as possible. Aidan started by lowering the intake rollers by about ¾ of an inch, and while that didn’t really even effect performance, the rollers, when flipped up, don’t fit within the size constraint, so the spacers were removed. Dexter modified the rollers themselves by replacing the chain we were using with 2 pieces of grip tread, flanked by a piece of green tank tread on either end of the grip tread. Through testing, this change seemed to help hold the balls in the intake better, but didn’t help with the actual action of intaking, and now, more specifically, intaking more than 2 bucky balls, which the robot seems to have trouble doing.

The intake has proven to be the most difficult part of the robot to perfect, while it does pick up bucky balls and large balls very easily at this point, intaking the third bucky ball is the difficult part for us now. What seems to happen is that the first two bucky balls get picked up very easily, but then after that, there is either not enough force being applied to the third bucky to get it into the intake basket, or the bucky is actually getting caught on the intake basket itself. Either way, the intake rollers should be able to pick up the third bucky ball without a problem, and they don’t, as of about 4:30 pm today.

During one block of work time, Aidan and Dexter worked on practicing the hanging while driving around, plus practiced general driving and scoring. During this time as well, Aidan added downward tension to the intake in an attempt to decrease the problem of the balls going under the intake rollers.

Dexter is getting much better at driving the robot, even with his quite limited practice that he’s been doing for the past couple of days. Hopefully at the competition this practice pays off in qualifications wins and a relatively high driver skills score.

Aidan, towards the end of the day, changed the bucky ball rollers by replacing the sprockets with larger, 30 tooth sprockets and changing the flap configuration so there are two of the largest flaps flanking 1 medium flap for added support. Plus, grip tread composing the rest of the roller, where flaps aren’t present.

The new, larger and more improved roller applies a lot more force to the bucky balls, getting them up the intake very easily, including the third one, the only problem is still the issue of the bucky balls going underneath the roller, which causes the other ones in the intake to spill out, and the one that was being picked up, obviously doesn’t.

At the end of the day, JT worked on the programming skills, at the time of writing this notebook entry (6:00 pm, the day

JT’s personal reflection on the current state of the programming skills routine (6:00 pm) – “Yesterday the routine wasn’t working at




before the South Texas Regional), we can achieve a score of 25 points. We are hoping to get something around 50‐60 points, so we’re basically halfway there! Hopefully for tomorrow it will all work out nicely.

all, but today it’s much much closer to working. Our progress is 10/10.. 10/50.”

Here are two images of the final robot (minus the most recent intake roller change) the left image is of the robot with the arm and hook fully lowered, and the right image is of the robot

with just the arm raised.




The right image is a close up of the intake mechanism, the pictured intake is different than the one we will be taking to the competition. The change is simply a different bucky ball roller that is made of a 30 tooth sprocket, and increments of 3 flaps, two large and one medium between the large flaps, plus, between each of these flap sections is all grip tread. The combination of using a more rigid flap configuration, as well grip tread, really helps force the bucky balls into the intake basket, the large sprockets help with this two, as well as keeping the bucky balls

inside the intake better. The left image is a bottom view of the hook mechanism under our intake basket, the picture isn’t very clear, so the pistons aren’t entirely visible, but basically the pistons retract, and the hook (the part that extends out the back of the intake basket) extends up, the nylon cord used to keep the hook from extending too far is also mildly visible in this picture as well (it is tucked

under the hook).




Here is a side view of the hook, the left image shows the pistons retracted and the hook

extended, plus the nylon cord used to keep the hook from extending too far up, and forward. The right hand image shows the pistons extended and the hook down.




Here is a very artsy photo of the hang lock that Dexter is very proud of, it shows off the

pneumatic gear lock, and even the pinion that is usually not visible in photos, that pinion is held in place by a lock bar and gets lowered down onto the plastic 84‐tooth gear, holding it in place

when we hang.




Here are all four views of our finished robot before competition, we seem fairly ready for the competition tomorrow. Dexter has practiced a fair amount, and his driving has improved drastically since the beginning of the season (the last time we competed in Houston). The

autonomous program is solid for the middle zone, but we don’t have one for the hang zone yet, hopefully we can get one programmed tomorrow, early in the morning. The other really nice thing is that over the past couple of months, Dexter has become friends with other really good

teams that might pick us for an alliance partner. We hope to do well at South Texas, and ultimately qualify for worlds.