The following is a tutorial on how to create the old Webble toy. This is not a modeling tut, as you will see, just a touch of what you can do with Reactor.

Step 1: Creating your Webble.
Body: Sphere: Radius (20)
Head: Sphere: Radius (10)
Eyes and Nose: Sphere: Radius (2)
Arms: Cylinder: Radius (5) , Height (60)
Weight: Box: Dim. (5x5x5)

Create a Plane (400 x 400) underneath the Webble

Now place all of the objects accordingly to resemble the picture.

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Step 2: Create a Rigid Body Collection
On the main menu bar select: Animation>reactor>Create Object>Rigid Body Collection

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Step 3: Open the Property Editor
On the main menu again, select: Animation>reactor>Open Property Editor

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Step 4: Give each object some Mass
Start by selecting an object and make the appropriate changes:
Body: Mass (10), Elasticity (1.0) and Mesh Convex Hull selected
Head: Mass (3) and Mesh Convex Hull selected
Eyes and Nose: Mass (1) and Mesh Convex Hull selected
Arms: Mass (2) and Mesh Convex Hull selected
Weight: Mass (20) and Mesh Convex Hull selected
Plane: Just mark this as "Unyielding" and Concave Mesh So it doesn't move but gives a collision surface

The goal here is to make the bottom of the Webble's body heavier that the rest. We don't give the Plane any mass due to the fact that we do not want it to move.
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Step 5: Group all of the Webble's parts
Move the "Weight" box into the center of your Webble's body as shown in the illustration. "Do not let the box extend out of your Webble's body". This weight will act as the center of gravity.
Select all of the items (Body, Head, Eyes, Nose, Arms and Weight) and on the main menu, select: Group>Group and name the group Webble_01 or just leave it to it's default.

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Step 6: Adding Items to the Rigid Body Collection
To have your animation work correctly, you have to add all of the item included in the animation to the Rigid Body Collection.
Click on the Rigid Body Collection and bring up the Modifier Panel
Normally, when you add a Rigid Body Collection to a scene it will automatically add an item that you may have selected on the screen. Delete this item by selecting it and pressing the delete button and we will add any item from a list.
Go ahead and click the "Add" Button.

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Step 7: Select Rigid Bodies
A screen will appear after pressing the "Add" button in the modifier panel. By holding down control, select the following items:
* Plane01
* Weeble_01 (Group)
Then press "Select"

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Step 8: Confirming selection
You should now have the Plane01 and Weeble_01 in the RB Collection Properties.

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Step 9: Positioning your Webble for animation
Move your Webble above the plane as shown. To get the full effect of the Webble's center of gravity, rotate it. Your Webble will achieve a better animation if he starts off center.

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Step 10: Previewing Animation
On the main tool bar, select: Animation>reactor>Preview Animation

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Step 11: Previewing Animation (cont)
Two separate screens will appear: Reactor Messages and Real-Time Preview
The Reactor Messages box will display any errors that may accure during the simulation.

To preview the simulation, just press "P" and your Webble should animate. Press "P" again to pause the animation or press "R" to reset and "P" to play again. In this screen you can use your wheel to Zoom, Hold down your wheel to pan, left click and drag to orbit and also right click on your weeble during the animation and you can move him and redrop or even throw him (Pretty cool)

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Step 12: One option
This is just a side note. If you were just trying to acheive a natural pose of a subject and are not going to animate as I did in this marble scene, here is what you can do. http://www.3dsmaxforum.com/image/marble-scene.jpg
* Go to the menu bar on the Real_Time Preview window and select: MAX>Update Max

This will update your viewport with the pose you see in the Real_Time Preview and no animation will be created. You will not see your viewport update until you close the Real-Time Preview

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Step 13: Creating your animation
To create your animation across the default 100 frames do the following:
* Goto the Main tool bar and select: Animation>reactor>Create Animation

This will create 100 frames of animaton. To be able to create more frames of animation, change the "Time Configuration" in the bottom right hand corner of your Max screen to the desired number of frames for this animation and then goto Step 14.

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Step 14: Animation timing and Collision distance settings
To get to this screen, click on the "Hammer" or "Utilities" tab on the Command Panel and select "reactor"
By default, the end frame of animation is set to 100. Change this to reflect how long of a reactor animation you desire.

One thing to note on this rollout is the Col Tolerance. By default, it is set to 3.937. If your animation looks like the pieces are hovering above the plane, you can adjust this down until you achieve what you are after.

I have uploaded a demo movie of several Webble's falling to give you an idea of how it should look. If you are using Firefox 3.0, it may try to block my site, just ignore it.

http://www.rickspitler.com/webbles.zip

Enjoy!

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Rick

http://www.3dartconcepts.com