ME250 Final Report

ME 250 DESIGN AND MANUFACTURING I

Fall 2015

PROJECT TITLE Team 33

ME 250 Section 003, Team #3 Team Members

Julia Roth Shadae BoakyeYiadom

Jolene Xin Wei Ng Jonathan Bruns Jarred McDuffey

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Table of Contents

1. ABSTRACT 2. INTRODUCTION

2.1 Problem Statement 2.2 Background of the Michigan Ninja Relay Competition

3. PROTOTYPE DESIGN 3.1 Squad and Zone Strategy Selection

3.1.1 Squad Strategy 3.1.2 Zone Strategy

3.2. Functional Requirements, Specifications, and Target values 3.2.1 Pick Up Cubes: Two Cubes at a Time 3.2.2 RMP speed: 2.69 inches/sec 3.2.3 Push the Largest Block: 3.75lb 3.2.4 Reach a height above the goal: 12 inch 3.2.5 Transportation and Safe Delivery of Cubes 3.2.6 Competition Size Specifications

3.3 Design Concepts and Subsystems 3.3.1 Preliminary Design Concepts 3.3.2 Pugh Chart 3.3.4 Design Selection 3.3.4 Final Design Development

Figure 2 shows the sketch of the RMP’s final design concept. 3.4 Analysis

3.4.1 Motor Selection 3.5 Final Design and CAD Model (6 points)

4. PROTOTYPE MANUFACTURING 4.1 Manufacturing Process

4.1.1 Manufacturing Plans and Resources 4.1.2 Challenges

4.2 Bill of Materials 5. PROTOTYPE TESTING

5.1 Preliminary Test 5.2 Scrimmage Results and Redesign Based on Scrimmage 5.3 Discussion of Competition Results

5.3.1 Competition Winners 5.3.2 Our RMP and Squad Performance 5.3.3 Possible Improvements

6.1 Project Summary 6.1.1 Design Overview 6.1.2 Design Evaluation

6.2 Recommendation for Mass Production 6.3 Future Project Ideas

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7. REFERENCES 8. ACKNOWLEDGEMENTS APPENDICES:

APPENDIX A: Preliminary Design Concept Sketches Appendix B: Calculations and Analysis

B.1 Motor Selection B.2 Position of Shovel Axles B.3 Center Distance between Timing Belt Pulleys B.4 Stopper Height

APPENDIX C APPENDIX C:

C.1 : Items Purchased C.2 Traded Parts:

1. ABSTRACT This report will outline the design, manufacturing, and testing process of the prototype of our Robotic Machine Player (RMP). It gives background to the assignment presented and describes the respective zone strategies and functional requirements of our RMP. We will detail the initial design concepts and subassembly systems prior to manufacturing, and expound on our decision and evaluation process. This report will then continue on to elaborate about the actual manufacturing process, resources used, and the ways our design was refined and developed in response to testing and further scrimmage. Finally, we will provide a summary of the competition results, and will conclude with recommendations for future mass production goals and project ideas.

2. INTRODUCTION 2.1 Problem Statement Our team was assigned to design, develop and build a RMP to compete in zone 4 of the Michigan Ninja Relay Competition. The RMP was to work together with other teams in the lab section, or squad, and score as many points as possible for the whole squad. 2.2 Background of the Michigan Ninja Relay Competition The competition was held during the ME250 Design Expo between the various squads. Each squad had four teams, and each team was assigned a quadrant of the arena, coined as a zone. The designed RMP was required to satisfy a size limitation, and could only be manufactured from the resources as stated in the game description. Each zone was unique and had its own obstacle. Zone one had a pyramid terrain, zone two was flooded with a sea of pingpong balls, zone three was hindered by a maze, and zone four had large blocks surrounding both the RMP and the goal basket, obstructing the pathway throughout the zone. Each squad had three minutes to work together to score as many points as possible. Teams would control their RMP

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and pick up 1.5” plastic cubes either from the RMP directly before or from its own zone and pass them to the next zone. The zone boundary walls had holes. Cubes could either be passed over the wall or through these holes. In the case of zone four, cubes were dropped into the basket. Table 1 shows the corresponding points scored when cubes were successfully passed over specified zones or to the goal basket.

initial zone 1 1 1 1 1 2 2 2 2 2 3 3 3 3 3 4 4 4 4 4

final zone 1 2 3 4 G 1 2 3 4 G 1 2 3 4 G 1 2 3 4 G

score 0 1 3 5 7 0 0 1 3 5 0 0 0 1 3 0 0 0 0 1

Table 1: Scoring table

3. PROTOTYPE DESIGN

3.1 Squad and Zone Strategy Selection 3.1.1 Squad Strategy All RMP’s would be mobile and would pass blocks over walls. Whenever cubes from multiple zones exist in any zone, cubes from the earliest zones would be given priority. There would be direct interaction with RMP1 and RMP2. RMP2 would retrieve some of its own cubes at the beginning of the relay. RMP3 would retrieve some of its own cubes initially and subsequently return to its start position to receive cubes from Zone 2. RMP3’s construction should make it capable of traversing the narrow, more direct maze option. 3.1.2 Zone Strategy We were assigned zone 4. Our zone strategy was to first push out of the enclosure made by the obstructing blocks and head downwards and then towards the border between Zone 3 and 4. Obstacles in the path would be pushed out of the way. As soon as cubes were passed over from RMP3, a clear path should have already been made between the border of zone 3 and 4 and the goal. Figure 1 shows the RMP travel path strategy. RMP4 will aim to keep running between picking up cubes and passing them to the goal. The only scenario that RMP4 will interact and receive cubes from RMP3 is if they happen to be at the border at the same time. The RMP should be able to pick up 2 cubes at a time, and be highly mobile in order to efficiently carry multiple cubes to the goal in a single trip. The RMP should also be able to hold cubes without them sliding out. This minimizes the risk during the transportation of cubes to the goal. The RMP must then lift the cubes up by 12” and drop them into the goal.

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Figure 1: RMP Travel Path Strategy

3.2. Functional Requirements, Specifications, and Target values 3.2.1 Pick Up Cubes: Two Cubes at a Time The RMP should be able to pick up two cubes at a time. Our initial aim was to be able to pick up three cubes at a time, however the development of our final design affected this criteria and the size limitations restricted the number of cubes the RMP could carry. The RMP should also be able to prioritize and pick up cubes from the previous zones first regardless of the orientation they were positioned in. In order to pick up two cubes, the weight the RMP was required to lift was 2X, where X is the weight of one cube. 3.2.2 RMP speed: 2.69 inches/sec The approximate maximum distance the RMP would travel is the diagonal of the zone, which is approximately 80.7”. The RMP would require to travel back and forth from the border of zone 3 and 4 to the goal, and our aim was for this whole process to ideally take one minute. By taking this distance and dividing it by time, we estimated the stated value for our desired speed. 3.2.3 Push the Largest Block: 3.75lb The force the RMP exerted on obstacles should be large enough to overcome the static friction of the largest block when accelerating from rest. The magnitude of this pushing force required, F = 2.5lb was found using a tension rope. A safety factor of 1.5 was applied on this pushing force. This was to ensure that the RMP was able to move blocks easily and would not get stuck among the obstacles.

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3.2.4 Reach a height above the goal: 12 inch The height of the goal basket was 11 inches above the ground. The RMP should drop the cubes from a point slightly higher than this in order to ensure that cubes fell safely into the goal. This determined the height the RMP should reach and store cubes at an inch above 11”. 3.2.5 Transportation and Safe Delivery of Cubes The RMP should be able to successfully transfer the cubes into the goal. It can only score points if it is able to deliver cubes to the goal basket. It should also be able to safely pass 2 cubes at a time to the goal. 3.2.6 Competition Size Specifications Each RMP has an initial size limitation of 10” x 10” x 12” at its starting position. It must also fit a control box of around 5” x 2.5” x 2.15” with a battery of size 2.8”x 2”x 0.6” mounted on top.

3.3 Design Concepts and Subsystems 3.3.1 Preliminary Design Concepts Design 1, the shovel, was for the RMP to pick up cubes with a dustpan. Rack and pinions would run on both sides. The shovel would be attached to the rack and thus would be lifted when the rack extended upwards. Cubes would be picked up by pushing them against the wall. The shovel had a weight attached to the back end, which would generate a moment and allow it to pivot on its back edge when lifted. This allowed for the safe storage of cubes in the shovel. At the ideal lifted height, the shovel would hit a triangular stopper, thus tilting it forward and allowing cubes to slide into the goal. Design 2, the clamp and bring over like a ferris wheel, was for the RMP to have an extending arm clamp. The arm would have two parallel metal plates. One would be motor driven to be able to clamp cubes against the other plate. Lifting would be done by pivoting the arm over the top of the RMP and swinging the clamp over the RMP. Similar to a ferris wheel, the clamp would be on pivots that would allow it to swing freely. This allows the RMP to stay facing one direction and would not require to turn around when picking and passing cubes. Design 3, the claw, was a bending arm with a claw which would allow the RMP to pick up cubes from above. The claw would have two pincers, which would be connected by gears to one motor. The claw would be able to grab a single cube at a time. The bending arm would then unfold and lift the claw. Upon release of the claw, cubes could be passed to the goal. Design 4, the motorized shovel, was a design similar to the shovel idea. However, this shovel would have a motorized hinged base, allowing the base of the shovel to tilt backwards and forwards. This would allow cubes to be safely secured while the RMP was moving, and also to slide easily into the goal basket when desired. The sketches for these designs can be found in Appendix A

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3.3.2 Pugh Chart We constructed a pugh chart and weighed the design concepts against each other on requirements derived mainly from the functional requirements. These include passing cubes, pushing obstacles, lifting, mobility, and other manufacturing considerations. The weights of each requirement were determined based on our best judgement. Our design candidates were scored individually by each team member for each requirement, and the average was then calculated to determine the matrix scores. Table 2 shows the tabulated Pugh chart.

Requirement Weight Design Concept 1: Shovel

Design Concept 2: Clamp and bring over like a ferris wheel

Design Concept 3: The Claw

Design Concept 4: Motorized Shovel

Pick up to two cubes at a time from where RMP3 drops the cubes

4 0 1 2 0

Push away the obstacles blocking the path of the RMP to the goal

5 0 1 1 0

Lift cubes high enough to reach into the goal

4 0 1 2 1

Dropping cubes into the goal

4 0 1 2 0

Ease in repicking up cubes that fall off the RMP or that fall in areas not planned

3 0 2 2 0

Durability 1 0 1 1 0

Manufacturability 3 0 1 3 0

Creativity 1 0 1 1 0

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Mobility 2 0 0 1 0

Speed 2 0 0 0 0

Able to safely secure cubes while travelling between the border and the zone

3 0 2 1 0

Total 0 4 1 4 Table 2: Pugh Chart

3.3.4 Design Selection From the Pugh chart, we settled on Design 1. This was not only due to its highest score, but also because we believed that it was the most efficient in completing the required task and would be the most straightforward to manufacture. Compared to the other designs, Design 1 required one less motor. Furthermore, since RMP3 might not drop all of the cubes in the exact same spot, the ability to pick up more than one cube from multiple areas at a time was a large factor in our design selection. Accomplishing this could significantly reduce the amount of cycles that the RMP would have to repeat to pick up and lift cubes. 3.3.4 Final Design Development While building our first mock up, we realized the inability for the design to lift to the desired height. This led to the development of a combined scissor lift and rack and pinion lifting mechanism, where the scissor lift could raise the entire rack and pinion assembly. The sketch for this can be found in Appendix A. However, despite the feasibility of this design concept, our CAD model revealed that the space restriction only allowed the scissor lift to add less than an inch in height. It was not only substantially harder to manufacture due to its complexity and additional components, but also impractical to assemble. In addition, manufacturing a direct connection between the shovel and the rack was not ideal, where it would require us to press fit a length of sheet metal into the back of the rack. This raised the need to connect the shovel to the rack using a different method. After further brainstorming, we introduced a pulley and string of a fixed length into the lifting subassembly. Instead of using racks on both ends of the shovel, we decided to lift the shovel by a single rack in the centre of the RMP. This evolved design solved the problem in connecting the shovel to the rack, enabled the RMP to lift to the desired height, and was also much simpler to manufacture. This final design still retained the same weight idea, as this was manufacturable and did not require additional motors for tilting the shovel. 3.3.5 Final Design Concept

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Our final design concept had three main subassemblies: the lifting subsystem, the weight tilting assembly, and the bumper driving system. The lifting subsystem was similar to that of a forklift. The shovel, pulley, and slider were the main parts of the lifting subsystem. The shovel was connected to a slider that slid up and down the back of the rack based on the work done by the pulley system. RMP4 would pick up cubes by pushing them with the shovel against the zone boundary of zone 3 and 4. A string of fixed length was attached across the top of the rack and fixed on one end to the RMP’s base. The other end was tied to the slider. As the pinions lifted the rack, the string length from the top of the rack to the ground would be forced to increase on the side tied to the base, and thus decrease on the side of the slider. This raised the slider up the rack holder, lifting the connecting shovel to the desired height — slightly above the rim of the goal basket. The weight tilting assembly involved a weight and the shovel. There was a weight attached to the back of the shovel, and the shovel was free to pivot on its axles. As soon as the shovel was lifted, the weight generated a moment along the back edge of the shovel, causing it to pivot backwards. This allowed cubes to slide into the shovel and be safely secured in the shovel during their transportation across the zone. Upon reaching the goal basket, the shovel was lifted to a height where it would hit a triangular stopper. This forced the shovel to tilt forward and allowed cubes carried to slide into the goal. The bumper driving system involved the motorwheels of the RMP and the bumper. The bumper was static, and attached at the back of the RMP. It was utilized to push the blocks in the zone obstructing the path of the RMP out of the way. The bumper was intended to evenly distribute the pushing force, and thus maintain the RMP’s stability while pushing. This driving system also involved two planetary gearbox motors that supplied power to efficiently push with the necessary driving force. Figure 2 shows the sketch of the RMP’s final design concept.

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Figure 2: RMP’s Final Design Concept Sketch

3.4 Analysis Refer to Appendix B for the respective calculations. 3.4.1 Motor Selection For the motors used to drive the RMP, its primary objective was to be able to push the large block obstacles throughout the zone. As measured previously in our functional requirements, the total pushing force the RMP should exert on obstacles, F = 3.75lb. A safety factor of 1.5 was applied on the pushing force required. This implied that each motor should at least be able to provide a driving force of 1.875 pounds (8.34 Newtons). For this requirement we decided to utilize two planetary gearbox motors, each with a gear ratio of 400:1. 3.4.2 Position of Shovel Axles and Weight

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From the CAD models, we found the location of the center of mass of the shovel. From this, we calculated a suitable distance where we could position the axles. We wanted the weight of the shovel to ideally play a role in tilting the shovel backwards, as we were afraid that the actual weight required might need to be larger, introducing unnecessary weight into the system. Also, we decided to place the weight aligned with the base of the shovel, as we wanted the line of action of the weight to line up with the axle at a reasonable angle when tilted back. 3.4.3 Center Distance between Timing Belt Pulleys Due to the introduction of the table, the center of motor shaft driving the timing belt pulley would be lifted to a height of 5” from the base. Using the CAD model, we found a rough distance between the pulleys, and eventually shifted the motor slightly to that we could get a value close to the actual center distance as calculated from the SDP/SI Center Distance Designer. 3.4.2 Stopper Height The stopper height was calculated after the introduction of the table. This height was essential as it would be the height we wanted the shovel to tilt at. We worked from calculating the ideal height of the shovel, and since the rack holder had a fixed length, we found a rough distance from the top of the rack holder to the base of the RMP. Using the fixed length of the string, we calculated the distance of the stopper from the top of the rack holder.

3.5 Final Design and CAD Model (6 points) Refer to Appendix C for all drawings and manufacturing plans. 3.5.2 From Sketch to CAD While working on the CAD, we realized the need to create space for the control box. This led to the building of a small table which could create space and hold the control box under the motor driving the pulley. The dimensions of the table could only be found from measuring distances on the CAD. From the CAD, we also realized that the weight might be too heavy and result in flipping the shovel when no cubes were carried. Thus we designed a weight backing plate and attached it onto the rising shovel holder as a precaution to limit the angle the shovel could tilt backwards. In the development of the CAD model, we modelled the angle we wanted the shovel to tilt back and then positioned the weight plate to be at a suitable distance from the shovel. Also, we only realized that the stoppers would be at a height too tall after building the CAD model. This prevented the shovel from being able to hit the stopper at the desired height. Thus we had to calculate a suitable height for the stopper to be at and designed the stopper to extend the tip of the stopper to reach that height. In addition, the placements of most components could not be determined until we started working on the CAD. This included the pillowblocks, motor wheels, rack holder and the alignment of holes. We could only find out that things would interfere with each other from the CAD model. Figure 3 shows the CAD for the final RMP design concept.

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Figure 3: CAD of Final RMP Design Concept

3.5.1 Design Details and Justification The lifting, weight tilting and bumper driving subsystems together were split into the following assemblies: Inner Rack Holder Assembly: The rack holder had to have an extruded rectangular cut with a slot to allow for an external slider to slide inside it while constraining its movement in the x and y axis. It also had to have a hole for the pulley rod to fit inside, and tapped holes to attach the stopper and rack to. The length of the rack holder was derived from maximizing the height limit. We wanted to fit a decent length of the rack while still fitting into the size limitations. The stoppers were triangular shaped in order to tip the shovel. It also had to be extended downwards as we wanted it to hit the shovel at the ideal height. Outer Rack Holder Assembly: The rack outer holder had to constrain the inner rack holder, and yet still allow the slider to pass through. It needed to have tapped holes to be attached to the base and for the attaching of the gear supports. The gear shaft was made to hold the timing belt pulley and the pinion gear. The diameter was the bore of the gear sizes and a hole was made to secure the pinion gear to the shaft via a spring pin. The gear supports had a hole to support the

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gear and extending arms to hug the outer rack holder. They were also angled in order to provide further horizontal support to the outer rack holders. The gear mount block were used as a means to attach the gear supports to the RMP, thus it was rectangular in shape where it was perpendicular to both the gear supports and the base of the RMP. The pillow blocks were mostly similar as to the one in the base assembly. They were cut from angled stock, reamed and drilled. They were dimensioned to be the length of the outer rack holder. Rising Shovel Holder Assembly: The rising shovel holder needed to have tapped holes to attach the shovel arms and weight backing plate to, and clearance holes for the pulley strings to pass through. It also needed a square sliding head where it was meant to slide smoothly up and down the rack holder. The giant ellipsed cut in the center was intended to reduce the amount of material used and thus make it lighter. The rack holder could only be placed in the center of the base due to interference with the motorwheels if pushed any nearer the edge, while the shovel was at the front of the RMP at the floor. Thus, the slider was also relatively long as it needed to connect the rack holder to the shovel. The shovel arms were Lshaped, as they had to not only extend out from the rising shovel holder, they also had to extend downwards, where the base of the RMP was higher off the ground and the shovel had to sit flat on the ground. The width of the arms were selected in order to provide sufficient clearance for the holes and for the pulley string. The weight backing plate had to be attached to the rising shovel holder, and had to be large enough to be in contact with the back of the shovel, but not unnecessary large. The shovel axles had to have grooves to place eclips to constrain unwanted movement of the shovel. It was also not unnecessarily long to cause interference with cubes picked up in the shovel. Shovel Assembly: The shovel had to be made out of two parts. The shovel front utilized sheet metal which could easily be bent to form a Ushape. Triangular sides were chosen for it to only tilt in one direction upon hitting the stopper. The shovel back was a rectangular plate where it could form an enclosure with the shovel front. The weight was a rectangular block to allow it to line up flat against the back of the shovel. Figure 4 shows the before lifting and at ideal height instants of the weight tilting system. As shown, the weight allows the shovel to tilt back, while the weight backing plate prevents it from over tilting. When the base of the shovel reaches 12”, the tip of the stopper triangle would hit the sides of the shovel. Any further increase in height would cause it to tilt forward.

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Figure 4: Weight Tilting Mechanism

Base Assembly: The Base was made with acrylic, and had holes to mount the motors and pillow blocks. There was a hole in the center to allow wires from the motors to pass through and connect to the control box. The bumper had six holes in it to allow attachment to the pillow blocks. It was rectangular and flat to ensure that it would have maximum surface area contact with the block obstacles. Figure 5 shows the flat back surface of the bumper. The hex rods were used where the BaneBots wheel had a hex mount. The connecting motor shafts were designed to be able to be press fitted into the hex rod, and a hole was to allow attachment to the motor shaft using a spring pin. The pillow blocks are generally similar, they were made with holes on both faces to allow a secure attachment of perpendicular faces to the base.

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Figure 5: Bumper Driving System

4. PROTOTYPE MANUFACTURING

4.1 Manufacturing Process 4.1.1 Manufacturing Plans and Resources In the process leading up to manufacturing, we acquired knowledge on manufacturing, mounting and assembly through reading instructions from the project resources folder on cTools and through learning from previous project examples. We modelled our design concept on Solidworks, and pulled up available CAD part files from vendor websites. From our Solidworks model, we were able to create detailed engineering drawings and this led to the drafting of the respective manufacturing plans. We also used SDP/SI’s center distance designer tool to calculate the center distance between the timing belt pulleys for use in our prototype model. In the manufacturing of our RMP, we utilized a variety of resources. This includes the mill, lathe, ME250 machine workshop, Duderstadt Center 3D printing cube, waterjet machine, and the CNC laser cutter. 4.1.2 Challenges A difficulty faced was in accurately bending or cutting the sheet metal at the desired marking line using the brake and the bench press. We were required to eyeball the placement of the metal plate, which made it impossible to precisely manufacture our sheet metal parts. Due to this resulted inaccuracy, we encountered issues when lining up the holes between mating parts. The hole placements were not identical to the one planned on the CAD model. This problem affected the assembly of the shovel and the table. In order to counter this, we used the waterjet to cut the clearance holes in the shovel bottom more specifically. We also measured all hole

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locations after bending to find the respective mating hole locations instead of following the CAD instructions directly. Additionally, we were also challenged by the lack of consideration for eclip clearances. Since we only allocated eclip grooves and did not display the eclips on the CAD model, we failed to ensure that the eclips would not interfere with other parts. It was during assembly that we found out that the screws for the gear supports would block the eclips for the gear shaft, and that the eclips on the pulley rod would touch the stopper. In order to resolve this, we remade the gear supports with one less clearance hole. Another major issue in the manufacturing process was the uneven and inaccurate dimensions of the stock material and parts. Our initial CAD model was based off dimensions stated in the tool kit list and from the mounting examples zip file provided on cTools. During assembly, we realized that the motor bracket dimensions were wrong due to the different gear ratio we used. In addition, the slider did not have a high enough tolerance to slide smoothly in the inner rack holder. We learnt to take precaution against this by first measuring dimensions based on the actual parts. The ideal slider dimensions was measured from the inner rack holder part, and we machined and attached a cube to size on top of the slider to allow it to slide more smoothly.

4.2 Bill of Materials A complete list of purchased and traded items can be found in Appendix D. Table 3: Bill of Materials

Part #

Description Material Description

Dimension Supplier

Total Quantity

Price (USD)

Justification of Material

001 Shovel Front 1/16” Aluminum Plate

2.56” x 22.6” 5.13” x 1.86”

Kit 1 Easy to be bent to create a boxlike holding area for cubes

002 Shovel Back ¼” Aluminum Plate

Kit 1 Able to add weight and tilt the shovel backwards. Thick enough to enhance sturdiness of the shovel

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003 Rack Holder Aluminum Square Tube Stock 1"x1", 1/8" Wall

Kit 1 Square space inside made it convenient to easily fit a sliding piece inside. Sturdy with sufficient thickness.

004 Rack Outer Holder

1” x 2” Aluminum Rectangular Stock

.75” x.52”x

.52” Kit 1 Able to be cut

once and made into two large pieces

006 Stopper PLA plastic Kit 2 3D printed as it was an odd shape

008 weight

¼” Aluminum Plate

.6” X 1.7”

Kit 1 The heaviest material available in the kit that could easily be cut to size

009 Rack Nylon rack, 24 pitch

8.5” Kit 1

010 Rising Shovel Holder


0.5”x0.5”x0.55”

Kit 2 Thick enough to slide through the rack holder

011 Shovel Arm ¼” Acrylic Plate

1.70”x .6”

Kit 1 Lasercut because of the weird shape and was decently strong

012 Weight Backing Plate

1/16” Aluminum Plate

1” x 0.38”

Kit 2 Thin and lightweight

013 Shovel Axle 3/8” Aluminum Rod

1.515” McMaster

2 $1.47

Multipurpose Unpolished 6061 Aluminum Chosen because of its diameter size

014 Gear Supports

Dowerin Plate

Kit 1 Lasercut because it was an odd

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shape and was decently strong

015 Gear Mount Block


Kit 1 Thick enough to drill holes on all sides

016 Pinion Gear 24 D.P.,24 Teeth, 20° Pressure Angle, Acetal/No insert spur gear

Kit 1

017 Upper Spur Gear

48 D.P.,72 Teeth, 20° Pressure Angle, Acetal/No insert spur gear

1.25” Kit 1

018 Gear Shaft 12L14 Carbon Steel Tight Tolerance Rod 1/4" Diameter

Kit 1 Sturdy and diameter fit the bore of the gears.

019 Pillowblock ¼ inch thick Angle Stock

1” x 1” x 2” Kit 2 Sturdy and already angled to shape. Provided support

020 Pulley Shaft 12L14 Carbon Steel Tight Tolerance Rod 5/16" Diameter

McMaster

3.04 Had the same diameter as the pulley’s bore

021 Pulley Acetal Pulley for Fibrous Rope

1”x 0.7” McMaster

1 1.80*2

Large enough to hold a fibrous rope

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022 Motor Connecting Shaft

Aluminum rod, 3/8" diameter

1” Kit 1 Chosen because sturdy, could be lathed to fit the gear bore.

023 Lower Spur Gear

48 D.P.,48 Teeth, 20° Pressure Angle, Acetal/No insert spur gear

1

024 Pulley Rope 3/16” diameter fibrous rope

34” Amazon

1 6.35 Chosen because it was strong and would not

025 Planetary Motor

Tamiya 72001 Planetary Gearbox Kit

Kit 1

030 Base Acrylic Plate (6 by 7 inch)

Kit 1 Easy to laser jet holes and also sturdy

031 Motor Table Bottom

Square Stock

2” Kit 2 Sturdy base and the dimensions could lift the platform high enough

032 Bumper ¼ inch Aluminum plate

6” x 7” Kit 1 Thick and large enough to to spread weight so that pushing wouldn not damage our RMP

033 Pillow block ¼ inch stock

1” x 1” x 1” Kit 2 Strong and supportive and in suitable

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shape

035 Bearings Flanged SS bearing

Flanged SS bearing

Kit 4

036 Planetary Motor

Tamiya 72001 Planetary Gearbox Kit

Kit 2

037 Front Wheel Axles

Kit 2 Sturdy and fit into the hex shape

038 BaneBots Wheel

BaneBots Wheel

27/8" x 0.4", 1/2"

Kit 2 Chosen because these wheels could provide more grip against the ground

039 Polypropylene wheels

Polypropylene wheels

3” 1/4” bore Kit 2

040 Table Top Level

1/16” Aluminum Plate

1 Light and could be bent easily

041 Pillow block bumper

Aluminum 90 Degree Angle Stock 1"x1", 1/4" thick

1” x 1” x 1” Kit 4 Chosen because of its shape

042 Frontwheel Pillowblock

Aluminum 90 Degree Angle Stock 1"x1", 1/4" thick

1” x 1” x 1” Kit 2 Chosen because of its shape

044 Front wheel Bushing

Flanged brass bushing

1/4" ID, 3/8" OD

Kit 2

045 Control Box Delrin Plate Kit Chosen

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Table Top because it was pretty sturdy and light and easy to lasercut

046 Driving Axle 12L14 Carbon Steel TightTolerance Rod, 1/4" Diameter

2 High tolerance to prevent shaft from fatigue from torsion motion

047 Hex Rod Multipurpose 6061 Aluminum Bar, 1/2" Hex Size

Kit 4 Fits inside the wheel

048 Motorwheel Pillowblock

Aluminum 90 Degree Angle Stock 1"x 1", 1/4" thick

1” x 1” x ½” Kit 2 Chosen because it was sturdy and was the right shape

049 Table Bottom Level

1/16” sheetmetal

6.65” x 2.6” Kit 1 Kit Chosen because it was lightweight and flat, and skinny allowing more room for the control box

050 Table Bottom Legs

Square Stock

2.7” Kit 2 Kit Chosen because of its sturdiness and height

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5. PROTOTYPE TESTING

5.1 Preliminary Test Prior to the scrimmage we tested whether two cubes would fit into the shovel in order to satisfy its ability to pick up two cubes at once. We also tested if the weight attached would successfully tilt the shovel far enough backwards to securely hold the cubes. Both of these tests were successful and we satisfied both the functional requirements of picking up two cubes at once and in successful delivery to the goal. We also tested if each motor wheel was fully functional prior to the scrimmage. We noticed that one of the motors attached to the wheel failed to run smoothly. To fix this motor wheel, we greased the inside of the planetary gearbox and filed down the rough edges of the gears. We also measured the dimensions of the RMP to ensure that the existing manufactured robot was within the size specifications.

5.2 Scrimmage Results and Redesign Based on Scrimmage Prior to the scrimmage, we discovered that the slider would get stuck while going up and down the rack as a result from the moment applied to it by the string or from the weight of the shovel. In order to rectify this, we attached a rectangular cuboid to the slider to minimize the angle it could tilt and thus prevent jamming. After retesting, the cuboid improved the smoothness of the slider, however it was attached with glue and would shift slightly when force was applied. Also, the slider still ultimately jammed on its way down. This was due to the fact that the majority of the rack holder was not horizontally constrained, and did not move vertically upwards when lifted. There was only pressure where the pinion was in direct contact with the rack and this contributed to the failure of the sliding assembly. In addition, we also found out that one of the pillow blocks did not align correctly with the holes on the bumper, thus affecting the assembly of the bumper to the RMP. Therefore, this had to be remade and hole locations had to be changed. During the scrimmage, we realized the rack was not in contact with the pinions, where the pinions were placed too far out. This required us to modify the design. The hole for the gear shaft on the gear supports was brought closer to the rack and the gear supports were laser cut again. This change also required us to shave the edge of the outer rack holder slightly in order to prevent interference between the gear shaft and the outer rack holder.

5.3 Discussion of Competition Results 5.3.1 Competition Winners In the Michigan Ninja Relay competition, Squad 4 won the 1st place with a score of 13 points, and Squad 7 follows behind in 2nd place with a score of 10 points. In 3rd place comes Squad 10 and Squad 2, with a tie of 5 points, and in 4th place is Squad 6 with a score of 4 points.

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5.3.2 Our RMP and Squad Performance In the course of the control box setup period, we struggled with identifying the corresponding motor wheel wires. In addition, some of the male electrical connectors were not attached securely enough to the motor wires and fell out easily. This caused us to be pressed for time when hooking up the RMP to the control box in the given time frame. During the actual competition, the RMP’s right wheel motor malfunctioned. This resulted in the RMP failing to have sufficient force to push its way out of the surround obstacle blocks, and was immobilized to transport cubes across the zone. Similarly, the other teams in our squad were held back by the difficulty in overcoming their individual zone obstacles. This led to the decision for our squad to pick up cubes from our own zones instead of any necessary prioritization. However, our squad ultimately failed to transport any cubes successfully across the zones and earned no points during the competition. 5.3.3 Possible Improvements To improve the performance of our RMP, we should verify that all motors function properly on the actual day of the competition. Grease could also be applied liberally on all the gears and bearings to ensure a smooth flow between any rotating torque transmission systems. In addition, we should have labelled the connecting wires in the RMP, organized them with a cable tie, and ensured that all male connectors were crimped tightly to motor wires beforehand to ideally execute a more efficient setup process. To achieve a better overall squad performance, we could have carried out a trial run prior to the competition day in order to gain experience, test the feasibility and efficiency of the squad strategy, and identify any issues neglected. 6. DISCUSSION AND RECOMMENDATIONS

6.1 Project Summary 6.1.1 Design Overview In summary, the project required us to design and manufacture an RMP capable of satisfying three major functional requirements. Firstly, the RMP needed sufficient power to push blocks out of its way. Secondly, it had to reach a height of twelve inches while staying within the size restrictions at the start of the match. Lastly, it had to be able to safely pass cubes to the goal. In order to facilitate the execution of these functions, our final RMP design consisted of the following three subsystems: a bumper driving system, a lifting subsystem and a weight tilting mechanism. The driving system utilized two planetary gearbox motors for sufficient power to push the blocks, and the attached bumper was intended to evenly distribute the pushing force and maintain stability while pushing. The lifting mechanism involved a rack and pinion and pulley assembly. This system worked similar to the lifting mechanism of a forklift. Pulleys were attached to the rack with a string of a fixed length which was pinned on end to the base, raising the shovel as the rack lifted. The weight system would generate a moment on the back of the shovel and cause it to pivot backwards when lifted, and the stoppers would force the shovel to

23

tilt forwards when at the ideal height. Minor design considerations include a table subassembly built to create clearance space for the control box.

6.1.2 Design Evaluation The rack and pinion forklift subsystem could be successful in lifting the shovel to the desired height. However, the major failure in this design was the belt size chosen. The timing belt used was from the MXL series, and the tooth pitch was too small to ensure a good grip between the timing belt pulleys. Thus the belt would jump easily and failed to lift the rack. Furthermore, there was a lack of constraints in keeping the rack holder vertical, and this affected its ability to lift the shovel. This design should definitely implement an additional part that would restrict the rack holder to only vertical motion. Lastly, the slider would jam in the rack holder while it was being raised as a result from the moment applied to it by the load carried. This component required a very high tolerance for a perfect fit, however, the odd shape of the slider prevented us from easily machining it to perfect size. With our given time restrictions, we could only counter this problem by sanding the edges of the slider and making a temporary cube to glue onto the existing slider. The cube did improve the smoothness, however attaching it with glue was not ideal. In the future, a perfectly machined sliding cube above and below the slider itself could be attached to ensure a better constraint on the slider sides. The weight tilting mechanism was successful in tilting the shovel as desired. It allowed the shovel to tilt back perfectly while carrying cubes, and allowed the shovel to tilt forward upon hitting the stoppers. The only flaw in this design is that it is very specific. If a heavier shovel load or different shovel height was desired, the weight tilting mechanism alongside the stopper height would have to be recalculated. The bumper driving system was a failure due to the inability to successfully drive the RMP out of the obstructing blocks. The decision to use planetary motors might not have been ideal due to its plastic composition, where the gears could easily jam. The metal gearmotor could have been a stronger alternative. Furthermore, the weight of the RMP itself was not considered and this might have affected the driving force the RMP could push with. The bumper however was a decent idea, where its surface area covered more than half of one face of the obstacle blocks. The additional table subassembly was also an essential feature in the design. It provided clearance to place the control box. However, it made it difficult to access the control box due to the table top, and this affected our performance. In the future, this table design could possibly be improved to include a sliding tray to slide the control box out. Alternately, the rack holder could be shifted to provide space to mount the control box at the side. Based on our current experience, we would have definitely done more calculations and analysis at the start. We could have modelled the RMP and obtained the relevant properties from the CAD, and from there verify that the motors chosen were strong enough. We would also have installed a timing belt pulley with a larger pitch to prevent the belt from jumping teeth. In

24

summary, it would be wise to have started the design process earlier. Using time effectively was a major component of this course. It was only during the actual manufacturing of the RMP when we identified problems that impacted its performance. Overall, the whole project was a huge learning experience in terms of team coordination, mechanical design, manufacturing, and in learning to use the machine shop.

6.2 Recommendation for Mass Production For mass production, we would have to consider the manufacturing costs and time efficiency in manufacturing. 3D printing is a manufacturing process likely to be eliminated as it is not time efficient and the printing material is also relatively costly. This applies mainly to the RMP’s stoppers. Instead, aluminium could be used instead to perform the same task and yet be manufactured in much less time. To further enhance manufacturing efficiency, parts such as the shovel back, weight plate, table legs and weight could be cut instead using resources such as the waterjet or laser cutter, which can be preset to accurately and efficiently cut out measurements as compared to utilizing human labor. Lastly, fasteners could be used more instead of tapping the pillow blocks, where tapping is a more tedious process.

6.3 Future Project Ideas For future projects, it would be interesting to see a sports game type competition, possibly such as soccer with the use of RMPs. The squads could come up with many strategies such as how many defensive bots or offensive bots they would want. This freedom of choice would definitely inspire many new creative ideas and strategies. It might also build further enthusiasm among students due to the popularity of such sports throughout the world.

7. REFERENCES ● ME 250 lecture slides ● ME 250 staff and Faculty(Trevor Sultana, Michael Umbriac, and all other GSI’s) ● Machine Shop faculty (Toby Donajwoski, John, and Charlie) ● SDP/SI Center Distance Designer, from http://sdpsi.com/estore/centerdistancedesigner

8. ACKNOWLEDGEMENTS Firstly, we would like to thank our GSI, Trevor Sultana, for his patient supervision and advice throughout the whole process, beginning with the strategy and ending with the competition at the Design Expo. We hope you get better soon and wish you all the best. Besides our GSI, we want to thank Michael Umbriac and Professor Kazuhiro Saitou for their lectures, John, Charlie and Toby from the Machine shop for the help and advice they provided while planning and manufacturing the parts and all the other GSIs for their help in overcoming difficulties. Next, we want to thank our peer mentor Amy Liu as well as the WaterJet staff for their assistance.

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http://sdp-si.com/estore/centerdistancedesigner

Finally, we would like to thanks Shell for sponsoring the ME 250 project.

APPENDICES:

APPENDIX A: Preliminary Design Concept Sketches A.1 The Shovel

26

A.2 The Clamp

A.2.1 The Clamp

27

A.3 The Claw

A.3.1 The Claw

28

A.4 The Motorized Shovel

A.4.1 Motorized Shovel Design

29

A.4.2 Details of Motorized Shovel Mechanism

30

A.5 The Developed Shovel with Scissor Lifting mechanism

A.5.1: Rack and Pinion and Scissor Lifting Mechanism for Shovel

31

A.5.2 Detail of Scissor Lifting Mechcanism. When lifted and closed.

A.5.3 View of Combined Scissors and Rack holder Lifting Mechanism

32

Appendix B: Calculations and Analysis B.1 Motor Selection The following analysis justifies our use of these motors: Wheel radius (r) = .0381 m Safety factor (fs) = 1.5 Force to push (F) = 5.56 Newtons TD = fsFr = (1.5)*(5.56)*(0.0381) = .3178 Nm Ts = 0.0173 Nm n0 = 13600 revolutions per minute TD ≤ ɣ*M*TS = 15*400*.0173 = 1.038 and .5889 ≤ 1.038 Therefore the 400:1 Planetary gearbox motor will be effective to use for pushing the blocks out of the way. B.2 Position of Shovel Axles From the CAD, Figure B.2 shows the following properties of the shovel (the origin was on the plane at the back of the shovel).

Figure B.2.1 Shovel Properties

x = 0.44 y = 0.72 The shovel is symmetric about the z plane running through its center , thus we only need to consider the x and y points of its center of mass. Figure B.2.2 details the reasons why we placed the axles at that location, where we wanted the weight of the shovel to play a role in helping to tilt the shovel backwards, but at an angle that would not be too extreme.

33

Figure B.2.2 Shovel Axle Location Calculation

34

B.3 Center Distance between Timing Belt Pulleys Figure B.3 shows the CAD model used to measure the distance between the timing belt pulleys.

Figure B.3.1 Horizontal Distance, x = 0.98055” Vertical Distance, y = 3.249” By Pythagoras Theorem, Center Distance = sqrt[(x)^2 + (y)^2)]

= sqrt[(0.98055)^2 + (3.249)^2] = 3.3937”

Figure B.3.2 shows the use of SDP/SI’s Center Distance Designer. We initially got a desired center distance, and then moved the motor horizontally to match it with the actual center distance calculated in the distance designer application. The 28 tooth timing belt pulley was chosen based on the diameter. Since the height of the motor shaft would be 0.656” above the table, the radius of the pulley had to be less than this distance, and this was a pulley in stock and within this value. The 42 timing belt pulley was chosen with similar justification, we did not want it to be too big to interfere with the screws on the outer rack holder. Thus we chose a

35

reasonable sized pulley which could still increase the torque as seen from the pulley ratio. The belt pitch was chosen based on the idea that it would fit onto the spur gears. However we have realized that this was not the case and that we needed a belt with a larger tooth pitch in order to successfully lift the shovel and prevent the jumping of teeth.

Figure B.3.2 SDP/SI Center Distance Designer

36

B.4 Stopper Height

Figure B.4.1: String Length Calculation at Start

Figure B.4.1 shows the starting positions of the lifting subsystem. One end of the string (green in color) is attached to the table top at a height of 4.35 above the ground, while the other end is tied to the slider. It is assumed that l1 is approximately the length of the rack holder: 9.5”. In addition, the pulley’s radius makes the approximate vertical distance from the top of the pulley to the tabletop to be 9.55” Then, the initial starting distance from the top of the pulley to the table top is approximately = 9.55” 4.35” = 5.2” and the top of the pulley to the holes in the rising shovel holder (which does not lie flat on the base) is approximately 9.23” as measured from the CAD model. Figure B.4.2 continues to show the instant when the shovel reaches the ideal height, that is when the base of the shovel is 12” above the ground. From there, it is possible to find the distance l2, the distance from the top of the rack holder that the tip of the stopper should be.

37

Figure B.4.2 Instant when Shovel is at Ideal Height

38

APPENDIX C C.1: Drawings

39

40

41

42

43

44

45

46

47

48

49

50

51

52

53

54

55

56

57

58

59

60

61

C.2 : Manufacturing Plans

Manufacturing Plan Part Number : ME 250 001 Part Name: Lifting_001_ShovelBottom Team Name : Team 33 Raw Material Stock : 1/16” Aluminium Plate

Step # Process Description

Machine Fixture Tool(s) Speed(RPM)

1 Waterjet Part

2 Bend both triangular

Brake Machine

62

sides up

Manufacturing Plan

Part Number : ME 250 002 Part Name: Lifting_002_Shovel Back Team Name : Team 33 Raw Material Stock : ¼” Aluminium Plate



1 Cut Aluminium plate to 5.75” x 2”

Horizontal Band Saw

300

2 Bring length of plate to 5.375in

mill vice ⅜ in 2 flute endmill, collet, parallels

840

3 Bring width of plate to 1.80in

mill vice ⅜ in 2 flute endmill, collet, parallels

840

4

Arrange the part upright

mill vice parallels

5 Set x and y datum points

mill vice edgefinder, drill chuck

900

6 drill #632 tapped holes on sides

mill vice #36 drill bit, center drill, parallels

1000

7 Arrange the part flat

mill vice parallels

8 find x and y mill vice edgefinder, drill chuck

900

9 drill #632 mill vice #36 drill bit, 1000

63

tapped holes on flat surface

center drill, parallels

10 tap all #632 holes

Tapping Device

#632 tap

11 File and Deburr

File, deburring tool

Manufacturing Plan

Part Number : ME 250003 Part Name: Rack Holder Team Name : Team 33 Raw Material Stock : Aluminum Square Tube Stock 1"x1", 1/8" Wall

Step # Process Description Machine Fixture Tool(s) Speed(RPM)

1 Cut one end of the stock of so to 9.5 inches

Vertical bandsaw

300

2 End mill to correct size cutting off .05 inches at a time

Mill Vice 3/4 inch 2flute endmill, collet

840

3 Cut a slit through the center of one of side of the square stock

Mill Vice collet,¼ inch flute

1400

4 Set up X and Y datum points at the end of the slit

Mill Edge finder,drill chuck

900

5 End mill .05 inch more making the slot .3

Mill Vice collet, ¼ inch flute

1400

6 Set up vice and find datum lines for X and Y

Mill Vice Edge finder,drill chuck

900

7 Center drill and drill holes on the either side perpendicular to the face of

Mill Vice Center Drill, #36 Drill Bit

1000

64

the slit.

8 Deburr the inside of the holes

Deburring tool

9 Install 632 tap and engage hole (nearest the end) in part with clockwise rotation. Repeat this for all other holes

Tapping machine

632 inch tap



900

11 Center drill and drill holes on the other two sides that have not been drilled into

Mill Vice Center Drill, Drill Bit #P

1000


Deburring tool

Manufacturing Plan

Part Number : ME 250 004 Part Name: Outer Rack Holder Team Name : Team 33 Raw Material Stock : 1” x 2” rectangular Stock



1 Cut one end of the stock of so to 8 ⅛ inches

Vertical bandsaw

300

2 End mill to correct size cutting off .05 inches at a time


840

3 Cut a slit on one end of

Mill Vice collet, 3/8 inch flute

1100

65

the stock just after the thickness to create 2 angled pieces

4 Turn the stock over and repeat step 3 to create two equal angled pieces

Mill Vice collet, ⅜ inch flute

1100

5 Set up X and Y datum points at the end of the slit

Mill Edge finder,drill chuck

900

6 End mill ends of each piece to size

Mill Vice collet, ¼ inch flute

1400



900

8 Center drill and drill holes on the larger three holes on one of the pieces


1000

9 Center drill and drill the two holes on the top of the larger piece


1000


Deburring tool

11 Install 632 tap and

Tapping machine

632 inch tap

66

engage hole (nearest the end) in part with clockwise rotation. Repeat this for all other holes

11 Repeat Steps 510 for the other angled piece

Manufacturing Plan Part Number : ME 250008 Part Name: Lifting Weight Team Name : Team 33 Raw Material Stock : ¼” Aluminum Plate

Step #

Process Description Machine Fixture Tool(s) Speed(RPM)

1 Cut Aluminum Stock 1.70”x .6” (slightly larger)

Vertical BandSaw

300

2 Mill all edges of the block to size cutting off .05 at a time

Mill Vice ¾ 2flute end mill, collet

840


Mill Vice

4 Center drill and drill holes Mill Vice Center drill, Drill chuck, #36 drill bit

1000

67

5 Install 632 tap and engage hole in part with clockwise rotation

Tapping machine

6/32 inch tap

6 Repeat step 4, for the other hole

Tapping machine

6/32 inch tap

7 Reverse tap, remove and clean tap.

Tapping machine

6/32 inch tap

8 Repeat step 6 for other hole Tapping machine

6/32 inch tap

Manufacturing Plan

Part Number : ME 250009 Part Name: Rack Team Name : Team 33 Raw Material Stock : Nylon Rack, 24 pitch, 12" length



1 Cut rack to 8.5 inches

xacto knife

2 Center drill and drill holes through the the front of the rack

Drill Press Vice Center drill, Drill chuck, 32 Drill bit

3600

3 Repeat step 2 for all holes

Drill Press Vice Center drill, Drill chuck, 32 Drill bit

3600

Manufacturing Plan

Part Number : ME 250010

Part Name: Rising Shovel Holder

68

Team Name : Team 33

Raw Material Stock : Aluminum 1/4” Stock

Step # Process Description Machine Fixture Tool(s) Speed(

RPM)

1 Waterjet Piece

2 Find datum lines for X and Y Mill Vise edge finder,

drill chuck

900

3 Center drill and drill all 4 holes

on the front side

Mill Vise Center Drill,

Drill Size

#36

1000

4 Deburr the holes Deburring

tool

5 Install 632 tap and engage

hole(nearest to end) in part

with clockwise rotation. Repeat

this for all other holes

Tapping Machine

632 inch tap

6 Reorient the part to one end

and repeat Steps 25 with the

two holes on the sides

perpendicular

7 Reorient the part to the other

end and repeat Steps 25 with

the two holes on the sides

perpendicular

Manufacturing Plan

Part Number : ME 250 012

69

Part Name: Weight Backing Plate Team Name : Team 33 Raw Material Stock : 1/16 Aluminium Plate



1 Cut a rectangular piece size 2”x 1”

Bench Shears

2 Center drill and drill two holes on one end

Drill Press Vice Center Drill, Drill Size #36

3 Deburr holes Deburring Tool

Manufacturing Plan

Part Number : ME 250 013 Part Name: Shovel Axle Team Name : Team 33 Raw Material Stock : Aluminum Rod, 3/16” diameter

Step #


1 Cut rod to length of 1.75 in Horizontal Band saw

300

2 Smooth out and deburr both ends

Lathe Collet cutting tool, file

750

3 measure the length calipers

4 touch edge to the surface and set Z

Lathe Collet cutting tool 750

5 Cut length to 1.51 in Lathe Collet cutting tool 750

70

6 Rezero Z and touch edge to outer diameter and zero X

Lathe Collet grooving tool

750

7 cut grooves Lathe Collet grooving tool, calipers

750

8 File edges Lathe Collet File 300

Manufacturing Plan Part Number : ME 250015 Part Name: Gear Mount Block Team Name : Team 33 Raw Material Stock : ¼ inch Aluminum plate


1 Cut plate to slightly larger than 1.5 by .6

vertical bandsaw

300

2 Mill to the exact size Mill Vice collet, ¾ 2flute collet

900

3 Set datum points X and Y Mill Vice edgefinder,drill chuck

900

4 Center drill and Drill the two holes on top side

Mill Vice center drill, drill size #29

1600

5 deburr hole deburring tool

6 Tap holes Tap Drill tapping drill #829

7 Reorient the piece to the side and set datum points X and Y

Mill

8 Center drill and drill the points two holes on the side

Mill center drill, drill size #36

71

9 Reorient the piece and repeat steps 78

Mill tapping drill #632

10 deburr and tap all four holes Tap Drill deburring tool, tap drill

Manufacturing Plan

Part Number : ME 250016 Part Name: Pinion Gear (24 teeth) Team Name : Team 33 Raw Material Stock : Pinion Gear


1 Hold part in vise Mill vise

2 Set datum points X and Y Mill Vise edgefinder,drill chuck

900

3 Center drill and drill hole (.0625” diameter)

Mill Vise center drill, #1/16 drill bit

1600


Manufacturing Plan

Part Number : ME 250 017 Part Name: Upper Spur Gear (72 teeth) Team Name : Team 33 Raw Material Stock : Spur gear (72 teeth)



1 Set datum points X and Y

Mill Vice Edgefinder, drill chuck

900

2 Center drill Mill Vice Center drill, 1800

72

and Drill #43 Drill bit

3 Tap hole 440 tap, tap handle, center


Manufacturing Plan Part Number : ME 250 012 Part Name: Lifting Supports Team Name : Team 33 Raw Material Stock : ⅜ Diameter Aluminium rod



1 Cut rod down to 3 in

Horizontal band saw

vise 300

2 Cut .1 in off both faces and file


750

3 measure the length

calipers

4 Touch the tool to the face and zero Z axis

lathe Collet cutting tool 1000

5 Cut down length to 2.7 in and measure

Lathe Collet cutting tool, calipers

1000

6 Finish cut to 2.6 in

Lathe Collet cutting tool

7 Zero Z axis

73

8 Touch cutting tool to diameter and zero X axis


9 Cut piece to .25 in diameter in .02 in increments


10 Chamfer both sides and file

file 300

11 Set X and Y on the mill

mill Vice edgefinder 900

12 Center drill and drill 1/16 in hole

Mill Vice parallels, center drill, 1/ 16 in drill bit

1000

13 Set the diameter

Lathe Collet grooving tool 750

14 Make cut for EClip

Lathe Collet grooving tool 750

15 Debur hole deburring tool

Manufacturing Plan Part Number : ME 250019 Part Name: Pillow Block Team Name : Team 33 Raw Material Stock : Aluminum 90 Degree Angle Stock 1"x1", 1/4" thick


Machine Fixture Tool(s) Speed (RPM)

1 Cut stock to 2 inches Vertical Band Saw

300

2 Hold part in vice Mill Vice

74

3 Mill one end of part, just enough to provide a fully machined surface.


840

4 Remove part from vise. Break all edges by hand.

Mill Vise File

5 Place part in vise to machine other end of part. Mill the part to 1.75" length, taking several passes at .05" per pass. Turn off the spindle, and measure part with calipers.

Mill Vise 3/4 inch 2flute endmill, collet


Mill Vise File

7 Remove cutter and collet. Install drill chuck. Return part to vise.

Mill Vise Drill Chuck

8 Find datum lines for X and Y.

Mill Vise Edge finder, drill chuck

900

9 Center drill and drill the three holes

Mill Vise Center drill, #25 drill bit, drill chuck

1000

11 Remove part from vise. Deburr the hole

Mill Vise Hole deburring tool

12 Return part to vise. The undrilled side facing down.

Mill Vise Drill chuck



900

14 Center drill and drill Mill Vise Center drill, 1000

75

the other three holes. #25 drill bit, drill chuck

15 Deburr both holes Mill Hole deburring tool

Manufacturing Plan Part Number : ME 250 020 Part Name: Pulley shaft Team Name : Team 33 Raw Material Stock : Aluminum Rod, 3/16” diameter

Step #


1 Cut rod to length of 6.75in Horizontal Band saw

300



750

3 measure the length calipers

4 touch edge to the surface and set Z


5 Cut length to 6.5 in Lathe Collet cutting tool 750

6 Rezero Z and touch edge to outer diameter and zero X

Lathe Collet grooving tool

750

7 cut grooves Lathe Collet grooving tool, calipers

750

8 File edges Lathe Collet File 300

Manufacturing Plan Part Number : ME 250 022

76

Part Name: Motor Connecting Shaft Team Name : Team 33 Raw Material Stock : ⅜” Aluminium Rod,



1 Cut stock ⅜” rod oversize, to around 1.375” length

Band Saw Vice 300 ft/mm

2 Hand file off the burr left from the band saw and install the material into the collet on the Lathe

Lathe File

3 Find datum points for Z axis

Lathe 1000

4 Move the Zaxis inward to cut approximately .020” off the end of part. to obtain a completely machined surfaced.

Lathe 1200

5 Remove the part and flip 180 degrees to repeat the process on the other end.

Lathe 1200

6 Remove the part and measure the length. Reinstall the part and continuing cutting in increments of 0.20” until the part is 1.25” long.

Lathe 1200

7 Find new datum Lathe 1000

77

points for Z and X axis

8 Move the tool to the end of the part and remove .080 of material off the diameter in the Xaxis to a length of .400 in the Zaxis. Then take a .005 deep cut, and rezero the Xaxis after this cut

Lathe 1200

9 Measure the diameter. Remove the difference to machine the diameter to 0.25”, traverse to the finish length of 0.450” in Z

Lathe 01” micrometer

10 Remove all burrs File, deburring tool

11 Install the drill chuck and the center drill. Move the tailstock within range of the part and lock it into position. Drill to a depth of approx. three quarters of the way up to the major diameter of the center drill.

Lathe Center Drill 1100

12 Remove center drill and install #78 drill bit into the drill chuck. Peck drill to a depth of 0.64”

Lathe #78 drill bit 1200

13 File and deburr File,

78

holes Deburring Tool

14 Hold part in vise Mill Barrel Vise


Mill Vise 900

16 Centerdrill and drill the .0625” diameter hole

Mill Vise Center drill, #1/16 drill bit, drill chuck

1000

17 Centerdrill and drill the other hole (.089” diameter hole)


1000

18 Deburr both holes Deburring Tool

Manufacturing Plan

Part Number : ME 250 023 Part Name: Lower Spur Gear (48 teeth) Team Name : Team 33 Raw Material Stock : Spur gear (48 teeth)



1 Set datam points X and Y

Mill Vice Edgefinder, drill chuck

900

2 Center drill and Drill hole (.0625” diameter)

Mill Vice Center drill, #1/16 Drill bit

1800


Manufacturing Plan

79

Part Number : ME 250 024 Part Name: Front Wheel Axles Team Name : Team 33 Raw Material Stock : ¼” Carbon Steel rod


1 cut rod to 4.3” and deburr edges

vertical band saw

300 ft/min

2 Touch side to make sure it’s fully machined. Break edges by hand

Lathe collet one contact cutting tool, file

400

3 machine other end as above and measure length with calipers


400

4 touch edge and set X to Zero

Lathe collet one contact cutting tool

400

5 Cut the part to 4.21" length, taking several passes at .05" per pass. Final cut at .01” remove from collet and measure length with calipers


400

6 touch edges and set X and Z to Zero

Lathe collet 400

7 cut groove for eclipse Lathe collett grooving tool

400

8 45°x.01” fillet on edges Lathe collet file 300

9 deburr groove deburring tool

80

10 switch sides and repeat steps 69 for other side

Manufacturing Plan Part Number : ME 250 025 Part Name: Frontwheel_Pillowblock Team Name : Team 33 Raw Material Stock : Aluminum 90 Degree Angle Stock 1"x1", 1/4" thick


1 Cut to 1 1/16” vertical band saw

300

2 Hold part in vise. Mill vise 3/4 inch 2flute endmill, collet

840


Mill vise 840


Mill file


Mill vise 3/4 inch 2flute endmill, collet

840


vise

81


Mill vise drill chuck


Mill vise edge finder, drill chuck

900

9 Centerdrill and predrill the pressfit hole.

Mill vise Center drill, P drill bit, drill chuck

800

10 Ream the pressfit hole to size.

Mill vise 0.3740" reamer

100

11 Remove part from vise. Deburr the hole.

Hole deburring tool





900

14 Centerdrill and drill the two holes.

Mill vise Center drill, #36 drill bit, drill chuck

1000

15 Deburr both holes. Hole deburring tool

16 Tap two #632 holes by hand, using the center to align the other end of the tap.

vise Center, drill chuck, #632 tap and handle

Manufacturing Plan

Part Number : ME 250032 Part Name: Bumper Team Name : Team 33 Raw Material Stock : ¼” Aluminum Plate



82

1 Cut the aluminum plate 7.5”x6.5”

Vertical Band Saw

230

2 File Edges File

3 Square up the stock

Mill Vice ¾ inch endmill and collet

900

4 Set datum points x and y

Mill Vice Edge finder 300

5 Center drill and drill

Mill Vice center drill, #36 drill

900

6 Adjust z axis Mill Vice

7 Drill .1 inch deep counterbore

Mill Vice ⅜ inch endmill

900

Manufacturing Plan

Part Number : ME 250033 Part Name: Pillow Block Team Name : Team 33 Raw Material Stock : Aluminum 90 Degree Angle Stock 1"x1", 1/4" thick

Step # Process Description Machine Fixture Tool(s) Speed (RPM)

1 Cut stock to 2 inches Vertical Band Saw

300

2 Hold part in vice Mill Vice



840


Mill Vise File

83


Mill Vise 3/4 inch 2flute endmill, collet


Mill Vise File


Mill Vise Drill Chuck



900

9 Centerdrill and drill the three holes


1000

11 Remove part from vise. Deburr the hole

Mill Vise Hole deburring tool


Mill Vise Drill chuck



900

14 Centerdrill and drill the other three holes.


1000

15 Deburr both holes Mill Hole deburring tool

84

Manufacturing Plan Part Number : ME 250 037 Part Name: Front Wheel Axles Team Name : Team 33 Raw Material Stock : ¼” Carbon Steel rod


1 cut rod to 4.3” and deburr edges

vertical band saw

300 ft/min

2 Touch side to make sure it’s fully machined. Break edges by hand


400

3 machine other end as above and measure length with calipers


400

4 touch edge and set X to Zero


400

5 Cut the part to 4.21" length, taking several passes at .05" per pass. Final cut at .01” remove from collet and measure length with calipers


400

6 touch edges and set X and Z to Zero

Lathe collet 400

7 cut groove for eclipse Lathe collett grooving tool

400

8 45°x.01” fillet on edges Lathe collet file 300

85

9 deburr groove deburring tool

10 switch sides and repeat steps 69 for other side

Manufacturing Plan

Part Number : ME 250 040 Part Name: Table Lift Team Name : Team 33 Raw Material Stock : 1/16 Aluminium Plate



1 Cut sheet metal to size of 2.6” x 6.64”

Bench Shears

2 Center Drill and drill holes on either end

Drill Press Vice center drill, drill bit size # 36

1000

3 Bend up both sides

Brake

Manufacturing Plan

Part Number : ME 250 041 Part Name: Bumper_Pillowblock Team Name : Team 33 Raw Material Stock : Aluminum 90 Degree Angle Stock 1"x1", 1/4" thick



300

86


840


Mill vise 840


Mill file



840


vise





900

9 Centerdrill and drill the four holes.


1000

10 Deburr all holes. Hole deburring tool

Manufacturing Plan Part Number : ME 250 042 Part Name: Frontwheel_Pillowblock Team Name : Team 33

87

Raw Material Stock : Aluminum 90 Degree Angle Stock 1"x1", 1/4" thick



300


840


Mill vise 840


Mill file



840


vise





900

9 Centerdrill and predrill the pressfit hole.

Mill vise Center drill, P drill bit, drill chuck

800

10 Ream the pressfit hole to size.

Mill vise 0.3740" reamer

100

88

11 Remove part from vise. Deburr the hole.

Hole deburring tool





900

14 Centerdrill and drill the two holes.


1000

15 Deburr both holes. Hole deburring tool

16 Tap two #632 holes by hand, using the center to align the other end of the tap.


Manufacturing Plan

Part Number : ME 250 046 Part Name: Motor Wheel Axle Driving Team Name : Team 33 Raw Material Stock : Aluminum Rod, .25” diameter



1 Cut rod to length of 1.25 in

Horizontal Band saw

300



750

3 measure the length

calipers

4 touch edge to the surface


89

and set Z

5 Cut length to 1.00 in


6 Find datum lines for X and Y

Mill Vice 900

7 Center drill and drill smaller hole

Mill Vice center drill, #45 drill bit

900

8 Find datum lines for X and Y

Mill Vice 900

9 Center drill and drill larger hole

Lathe Vice center drill, #16 drill bit

300

Manufacturing Plan Part Number : ME 250 047 Part Name: Hexagon for rear wheels Team Name : Team 33 Raw Material Stock : hex rod Tools needed: 3/4 inch 2flute endmill, collet, file, drill chuck, edge finder, center drill #1 drill bit, .2495” reamer


1 Cut .425” of hex rod vertical band saw

300

2 Hold part in vise Lathe hex collet

cutting tool

90

3 cut one end of part, just enough to provide a fully machined surface.

Lathe hex collet

840

4 Remove part from collett. Break all edges by hand.

file

5 Place part in collett to machine other end of part. cut the part to .30" length, taking several passes at .05" per pass. Turn off the spindle, and measure part with calipers.

Lathe hex collet

cutting tool 840


file

7 Install drill chuck. Return part to collet.

Lathe hex collet

8 Center drill and predrill the press fit hole.

Lathe Center drill, #1 drill bit

800

10 Ream the press fit hole to size.

Lathe .249” reamer

100

11 Remove part from collet. Deburr the hole.

Manufacturing Plan Part Number : ME 250 048 Part Name: MotorWheel_Pillowblock Team Name : Team 33 Raw Material Stock : Aluminum 90 Degree Angle Stock 1"x1", 1/4" thick

91


1 Cut to 1 1/16” and cut one side of angle stock to ⅝ inch

vertical band saw

300


840


Mill vise 840


Mill file



840


vise

7 Repeat Steps for the ⅜ inch edge until it is to size





900

10 Centerdrill and drill the four holes.


1000

11 Deburr all holes. Hole

92

deburring tool

Manufacturing Plan

Part Number : ME 250 049 Part Name: Control Box Table Team Name : Team 33 Raw Material Stock : 1/16 Aluminium Plate



1 Cut Sheetmetal to 5 inch by 1 inch

Bench Shears

2 Center drill and drill two holes on either side

Center drill, drill size #36

1000

3 Deburr Holes Deburring Tool

Manufacturing Plan

Part Number : ME 250 050 Part Name: Table Bottom Legs Team Name : Team 33 Raw Material Stock : Aluminum ½” Square Stock


1 Cut Square stock oversize to 2.85”

Vertical Band Saw

300


840

3 Mill one end of part, Mill vise 840

93

just enough to provide a fully machined surface.

4 Rotate and place part in vise to machine other end of part. Mill the part to 2.7" length, taking several passes at .05" per pass. Turn off the spindle, and measure part with calipers.


840


vise

6 Find datum lines for X and Y. Use a vise stopper to retain datum lines

Mill vise edge finder, drill chuck,

900

7 Centerdrill and drill the two holes 0.25” in depth


1000

8 Flip around and hold part in vise, drill one hole 0.25” in depth


1000

9 Flip to standing and reposition stopper. Find new datum lines for X and Y.

Mill vise edge finder, drill chuck,

900

10 Centerdrill and drill one hole 0.25” in depth


1000

11 Flip around and drill one hole 0.25” in depth


1000

12 Deburr all holes Hole deburring tool

94

13 Tap one #632 holes by hand, using the center to align the other end of the tap.


14 Tap four #440 holes by hand, using the center to align the other end of the tap.


APPENDIX C: C.1 : Items Purchased

Name Description Dimensions Supplier Qty Price Notes

Item for shovel Axle

3/8” Aluminum Rod

12” McMaster 1 $1.47

Pulley Shaft 12L14 Carbon Steel Tight Tolerance Rod 5/16" Diameter

12” McMaster 1 $3.04 http://www.mcmaster.com/#standardsteelrods/=ztazc6

Pulley Acetal Pulley for Fibrous Rope

1”x 0.7” McMaster 2 $1.80 each

http://www.mcmaster.com/#8901t11/=zta88f

Pulley Rope 3/16” diameter Fibrous rope

Amazon $6.35 http://www.amazon.com/RopeKingDBN31650DiamondBraided/dp/B005TLUYOM/ref=sr_1_3?ie=UTF8&qid=1447549666&sr=83&keywords=3%2

Timing Belt Pulley (28 teeth)

Light Weight Mxl Timing Belt Pulley, 1/4" Belt

McMaster 1 $6.50

http://www.mcmaster.com/#1254N22

95

http://www.mcmaster.com/#standard-steel-rods/=ztazc6







http://www.amazon.com/Rope-King-DBN-31650-Diamond-Braided/dp/B005TLUYOM/ref=sr_1_3?ie=UTF8&qid=1447549666&sr=8-3&keywords=3%2F16+fibrous+rope












Width, 0.88" OD, 28 Teeth

Timing Belt Pulley (42 teeth)

Light Weight Mxl Timing Belt Pulley, Fits 1/4" Belt Width, 1.24" OD, 42 Teeth

McMaster 1 $6.88 http://www.mcmaster.com/#1254N26

Timing Belt Mxl Series Neoprene Timing Belt, .08" Pitch, 96 Trade Size, 9.6" Outer Circle, 1/4" W

McMaster 1 $4.37 http://www.mcmaster.com/#7887k81/=108ah93

PURCHASE TOTAL

$32.21

Order Number Shipping Costs

1116JNG $5.30

1123JNG $10.46

SHIPPING TOTAL $15.76

TOTAL COST = $32.21 +$15.76 = $47.97 C.2 Traded Parts:

Tradein part Tradeout part(s)

From Positive Trade Deficits

Description

Double Gear Box 2 Planetary Gearbox

Crib $0 Needed 3 planetary gearbox

96




http://www.mcmaster.com/#7887k81/=108ah93



97

Documents

ME250 Final Report