3ds Max Reactor Robo Arm

8/2/2019 3ds Max Reactor Robo Arm

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below it to download the scene, or download the scene including the bones by clicking the

link below Picture 3h, or just watch the pictures if you do not feel like actually doing any of

this right now.

Picture 3a.

Download scene here (robotleg_start.zip)

The red dots in the picture above represent the pivot of the object. In the scene you can

download, I have already moved them to the correct position. The UpperLegs pivot ispositioned at exactly the same position as the pivot of Cylinder01, and LowerLegs pivot is

at the same position as the pivot of Cylinder02. When switching to the top view, they are

all aligned. It is essential that the bones you add start or end exactly at those pivot points.

A way of making sure the bones are positioned correctly is to snap to pivots. When you use

this method it is also essential that all the pivots are aligned when viewing from the top. If

in your robot they arent and it is too complex or difficult to align them, you can skip thefollowing snap settings and just draw the bones, select them all and move them to the

center of the leg (Top view). To use the snap setting, right-click the Snaps Toggle button onthe main toolbar and select Pivotand clear others if necessary (see Picture 3b). Now click

the Snaps Toggle button again (with the left mouse button) to enable it.
http://www.3dvalley.com/tutorialsdata/robotrigging/robotleg_start.ziphttp://www.3dvalley.com/tutorialsdata/robotrigging/robotleg_start.ziphttp://www.3dvalley.com/images/RiggingRoboticJointsin3DStudioMax_5394/clip_image003.gifhttp://www.3dvalley.com/tutorialsdata/robotrigging/robotleg_start.zip


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Picture 3b.

Click theBones button in the Systems section on the Create tab of the Command Panel as

displayed in Picture 3c below. Choose SplineIKSolveras the IK Solverand enableAssign to

Children (you can use another IK Solver or none at all, if you prefer).

Picture 3c.

Now draw the bones, by clicking on the spots 1, 2, and 3 shown in Picture 3d and then

right-click anywhere in the viewport to stop. Spots 1, 2 and 3 are the pivot points of

Cylinder01, Cylinder02, and Cylinder03.
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Picture 3d.

When the Spline IK Solverdialog shown in Picture 3e below opens, just click OK.

Picture 3e.

Now before you link the bones to the leg, you should make sure that the pivots of the bones

are positioned correctly on the pivot of the limbs, the Spline IK Solver we added moved

them slightly. To move a bones pivot, click the Affect Pivot Only button on theHierarchy

tab of the Command Panel, and disable the Enabled button on the Motion tab of the

Command Panel.


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Picture 3f.

Then select the pivot of the bone and move it to the correct position. Make sure you zoomin and place it exactly in the center ofthe limbs pivots. You also might want to disable thesnap to pivot setting first by clicking the Snaps Toggle button again. If for some reason you

cannot get them in the right position, there is no need to continue, as the whole setupdepends on the pivots position.

When you are sure the pivots are positioned correctly, select Cylinder01 and link it toUpperLeg. Select Cylinder02 and link it to the LowerLeg, and select Cylinder03 to

LowerLeg as well. To link one object to another click the Select and Link button on the

main tool bar, select the object you want to link and drag to the object you want to link to.

If you do it correctly, the object you link to, will flash white once.

We will use the same select and link method to link the objects to the bones, instead of

using a Skin modifier. Link UpperLeg to the upper bone, and link LowerLeg to the lower

bone.

Picture 3g.

When you done all of the above, or download the scene including the bones by using the

link below, select the IK Chain or any of the point helpers and move it. The knee joint


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should now operate as shown in Picture 3g, without any of the objects deforming during

movement.

Picture 3h.

Download scene here. (robotleg_end.zip)

4. Another Approach

Before we continue with this leg and add some muscles, we will use another method ofrigging this leg. As someone kindly pointed out to me, there is no absolute need to use

bones . If you are new to rigging characters or robots in particular, you may want to go for

the bones method discussed above, but a robot is often a skeleton by itself, eliminating the

need for bones. 3D Studio Max allows any object to act like a bone, and allows you also toassign IK solvers to any hierarchical set of objects. Also in this type of bone setup, it is

absolutely imperative that the pivots of the objects are in the correct position. We will

illustrate this with some pictures later.

To make this work with the previous example (delete the previous bone structure or use the

scene you downloaded earlier), and link the objects to each other as followed:

Cylinder03 LowerLeg

LowerLeg Cylinder02

Cylinder02 UpperLeg

UpperLeg Cylinder01

Press the Schematic View (Open) button on the main toolbar to check if the hierarchy is

now correct as displayed in Picture 4a.
http://www.3dvalley.com/tutorialsdata/robotrigging/robotleg_end.ziphttp://www.3dvalley.com/tutorialsdata/robotrigging/robotleg_end.ziphttp://www.3dvalley.com/images/RiggingRoboticJointsin3DStudioMax_5394/clip_image010.gifhttp://www.3dvalley.com/tutorialsdata/robotrigging/robotleg_end.zip


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Picture 4a.

Now all you need to do is add an IK Solver to this hierarchy to make it act like a robotic

leg. You can use the IK Solver you prefer, but in this example, we are going to use theHistory Independent solver. Select Cylinder03, choose HI Solver from the IK Solvers

section in the Animation menu, and select Cylinder01. To prevent you from linking the

solver to UpperLeg instead of Cylinder01, use the Select by Name option, which basicallymeans you should press the H key on your keyboard after you choose HI Solverfrom the

menu, and then pick Cylinder01 from the list, instead of clicking on it in the viewport.

If you performed the previous tasks correctly, the results should be like in Picture 4b with

the IK Chain selected. If you move the IK Chain the leg should work. To make the task of

animating this leg a bit more convenient, you should link the IK Chain to a Point Helper.

A Point helper can be created by clicking the Point button in the Helpers section of the

Create tab on the Command Panel, and clicking somewhere in the viewport, as depicted inPicture 4b below. In this case, I suggest you place it somewhere at the bottom of the leg.

Use the same Select and Link method as discussed earlier to link the IK Chain to the Point

helper, so you can animate the leg by moving the Point helper.

Picture 4b.


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If your robot has a complex geometry and animating the individual objects slows down

your computer too much, you can configure 3D Studio Max to display the objects as bones.

When using our example leg from the previous steps, you should select Cylinder01, 02, 03,UpperLeg, and LowerLeg, and select Bone Tools from the Character menu. Enable the

Bone On option on theBone Tools dialog as shown below.

Picture 4c.

Next, open the Display tab on the Command Panel, scroll down, and in the Link Display

section enable theDisplay Links option and theLink Replaces Objectoption.

Picture 4d.

The results should be as depicted in Picture 4e below.


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Picture 4e.

Alternatively, you can enable only the Display Links option and right above the Link

Display section enable the Display as Box option in the Display Properties section. Theresults should be as depicted in Picture 4f below.

Picture 4f.

Download the scene here. (robotleg_ik_end.zip)

5. Muscles

As I mentioned earlier, the leg used in the example above is not very realistic; it needssome muscles to make it move automatically and at the same time give it some strength.

You can make up your own mechanisms, but you can also use one of the three main

methods used in modern real world robots:

Electrical motors

For the example leg from above, this would be the easy way out, as you would only have

to increase the size of the knee joint and modify it into to something like shown below in

Photo I, so it becomes viable an electrical motor could fit inside. Additionally, rigging therobot is easy as you can use one of the methods we discussed earlier.
http://www.3dvalley.com/tutorialsdata/robotrigging/robotleg_ik_end.ziphttp://www.3dvalley.com/tutorialsdata/robotrigging/robotleg_ik_end.ziphttp://www.3dvalley.com/images/RiggingRoboticJointsin3DStudioMax_5394/clip_image016.gifhttp://www.3dvalley.com/images/RiggingRoboticJointsin3DStudioMax_5394/clip_image015.gifhttp://www.3dvalley.com/images/RiggingRoboticJointsin3DStudioMax_5394/clip_image016.gifhttp://www.3dvalley.com/images/RiggingRoboticJointsin3DStudioMax_5394/clip_image015.gifhttp://www.3dvalley.com/tutorialsdata/robotrigging/robotleg_ik_end.zip


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Photo I. Industrial robot arm powered by electrical motors.

Hydraulic/Pneumatic/Magnetic pistons

Another commonly used method to power robots arepistons. A piston (see Photo II below)

is basically consists of a metal bar that goes inside a tube. Pressurized air or oil is pumped

into the piston to push out metal bar. This is usually the sound you here when a robotmoves. If you want to make them realistic, you should attach a hose to it, which leads to a

compressor somewhere in or on the robot. These hydraulic or pneumatic pistons are much

more powerful than electrical motors. Smaller pistons may use magnetic force to either pullor push the metal bar. The latter would have electrical wires attached to it, instead of a

hose.

Photo II. Crane powered by hydraulic pistons.

Picture 5a and 5b show our second example leg. It includes a piston that is made of two

cylinders called Piston_PA and Piston_PB. Two additional cylinders (P_Axis_A and

P_Axis_B) form the axis of the pistons parts.
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Picture 5a. Picture 5b.

As you can see in Picture 5c below, we already rigged the leg with two bones and an

IKSplineSolver. You can download the scene by clicking the link below the picture.

Picture 5c.

Download the scene here. (robotleg_pistons_start.zip)

First, we will link the pistons parts to the leg as followed:

P_Axis_A UpperLeg

P_Axis_B LowerLeg

Piston_PA P_Axis_A

Piston_PB P_Axis_B

The hierarchy of the leg should now be exactly like in Picture 5d.
http://www.3dvalley.com/tutorialsdata/robotrigging/robotleg_pistons_start.ziphttp://www.3dvalley.com/tutorialsdata/robotrigging/robotleg_pistons_start.ziphttp://www.3dvalley.com/images/RiggingRoboticJointsin3DStudioMax_5394/clip_image021.gifhttp://www.3dvalley.com/images/RiggingRoboticJointsin3DStudioMax_5394/clip_image020.gifhttp://www.3dvalley.com/images/RiggingRoboticJointsin3DStudioMax_5394/clip_image019.gifhttp://www.3dvalley.com/images/RiggingRoboticJointsin3DStudioMax_5394/clip_image021.gifhttp://www.3dvalley.com/images/RiggingRoboticJointsin3DStudioMax_5394/clip_image020.gifhttp://www.3dvalley.com/images/RiggingRoboticJointsin3DStudioMax_5394/clip_image019.gifhttp://www.3dvalley.com/images/RiggingRoboticJointsin3DStudioMax_5394/clip_image021.gifhttp://www.3dvalley.com/images/RiggingRoboticJointsin3DStudioMax_5394/clip_image020.gifhttp://www.3dvalley.com/images/RiggingRoboticJointsin3DStudioMax_5394/clip_image019.gifhttp://www.3dvalley.com/tutorialsdata/robotrigging/robotleg_pistons_start.zip


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Press the H key on your keyboard, select P_Axis_B, and click the Pickbutton. Piston_PA

now changes its orientation. To make sure it point in the original direction, enable the Keep

Initial Offsetoption on the Parameters section on theMotion tab of the Command Panel, asdepicted in Picture 5g below. (The parameters section opened automatically when you

added theLook Atconstraint.)

Picture 5g.

Repeat this step for the other part of the piston, in other words: select Piston_PB, select

Look Atconstraint from theAnimation menu, pick the P_Axis_A as the target (using the Hbutton to pick it). Also enable the Keep Initial Offsetoption again. So what we did is make

one part of the piston looks at the opposite parts axis. The orientation is depicted with a

blue line. If you select the helper Point03 and move it again, you will see that the metal bat

slides neatly into the tube, as shown in Picture 5h below.

Picture 5h.

Download the scene here. (robotleg_pistons_end.zip)

To make it more realistic, we need to attach a pipe or hose to the hydraulic or pneumaticpiston, and we need to make sure it moves and/or bends when the leg moves. There are
http://www.3dvalley.com/tutorialsdata/robotrigging/robotleg_pistons_end.ziphttp://www.3dvalley.com/tutorialsdata/robotrigging/robotleg_pistons_end.ziphttp://www.3dvalley.com/images/RiggingRoboticJointsin3DStudioMax_5394/clip_image026.gifhttp://www.3dvalley.com/images/RiggingRoboticJointsin3DStudioMax_5394/clip_image025.gifhttp://www.3dvalley.com/images/RiggingRoboticJointsin3DStudioMax_5394/clip_image026.gifhttp://www.3dvalley.com/images/RiggingRoboticJointsin3DStudioMax_5394/clip_image025.gifhttp://www.3dvalley.com/tutorialsdata/robotrigging/robotleg_pistons_end.ziphttp://www.3dvalley.com/tutorialsdata/robotrigging/robotleg_pistons_end.zip


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many ways of doing this, but a relatively easy one is to use the extended primitive Hose.

The advantage of using the Hose primitive is that you dont need to rig it; no bones, and no

IK. Instead, we are going to add two extra Cylinders, in addition to the Hose, and let theHose start and end at those cylinders.

In Picture 5i below you can see where we placed the two cylinders. The cylinder on the leftis linked to UpperLeg, and the other is linked to Piston_PA. These cylinders represent the

entry points of the hose, or the connector of a wire for example. You will probably want touse something more sophisticated than a cylinder, but make sure it is a separate object.

Picture 5i.

Next, create the hose by selectingExtended Primitives on the Create tab of the CommandPanel, clicking theHose button, and drawing a hose in any viewport, as shown in Picture 5j

below. Dont worry about its size, location, or shape yet.

Picture 5j.

On the Modify tab of the Command Panel, enable the Bound to Object Pivots. Click the

Pick Top Objectbutton and click on the left cylinder. Click the Pick Bottom Objectbuttonand click on the right cylinder (or use the H key on your keyboard).


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Picture 5k.

Depending on the orientation of the cylinders we use to connect the hose and the viewport

you created them on, you may have to rotate the pivot of one or both cylinders. So ifnecessary, select the cylinder, enable the Affect Pivot Only button (picture 3f), and rotate

the pivot. While you rotate the pivot, the hose will bend with it so you can easily see when

it is at the right angle.

When the hose is correctly aligned to the cylinders, click the hose again, scroll down below

on the Modify tab, and disable the Flex Section Enable option as shown below in Picture5l. Also decrease theDiameter: value in theHose Shape section to a value that is less than

the cylinders.

Picture 5l.

As you can see, the hose is too long and needs to hang more tightly against the leg. You can

do this by decreasing the Tension values (see Picture 5k). In the final images below, we

used 25 for both cylinders. If you move the leg again using on of the helpers, you will

notice that the hose will stay in position and even bend when it has to. Click on one of theimages to see the final animation.


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3ds Max Reactor Robo Arm