Setting Up the Simulation

Introduction to reactor

Preparing Output

 

Autodesk 3ds Max Tutorials > Special Effects > Introduction to reactor > 

Using Hand-Animated Rigid Bodies

Something that you will often want to do is to use hand-animated rigid bodies in a physical simulation. These rigid bodies are referred to as unyielding rigid bodies and have the Unyielding property turned on in the Rigid Body Properties dialog. They behave as their keyframes dictate and other rigid bodies react to them. You do not need to give them a mass. In this example, you will hand-animate your toy box so that it tips over and spills the toys out onto the floor.

Add hand-animated rigid bodies to a physical simulation:

1. Select the toy box.
2. Open the Rigid Body Properties dialog. On the Physical Properties rollout, turn on Unyielding.

   

3. Turn on Auto Key and move the time slider to frame 60. Rotate the box clockwise by about 125 degrees so that the objects will pour out when physically active. Turn off Auto Key. Be careful to move your floor below the final position of the toy box so that the two are not interpenetrating. This would not generate errors in simulation, but would look strange.
   NoteYour toys may exhibit some strange behavior when you are hand-animating the box, but don't be alarmed. This is because the objects have not been keyframed yet. They will, however, behave correctly in the preview window.
4. Click Preview Animation.

   Your box tips over and the toys pour out onto the floor. You may want to increase the size of your floor so that the toys don't all wobble over the edge.

   

5. At this stage, you may want to tweak the physical properties of your objects. For instance, if your objects are piling up as they fall out of the box, you can reduce their friction and the friction of the floor, so that they spread further after colliding with the floor and the other toys.
   NoteRemember that to change the physical properties, you must open the group and change the properties of the group helper object. You can change the properties of more than one object at a time.