Animating with Physical Properties

The Asset browser Physical Properties folder contains Physical Property assets that you can use to simulate complex interactions between 3D objects and their environment. The Physics solver lets you create collision and rigid interaction effects that are difficult to obtain with keyframing and motion capture techniques.

The three physical descriptions, Rigid Body, Ragdoll, and Joint provide a description of the objects in the scene to the Physics Solver. You can use the Rigid body physical description to prevent interpenetration of characters, objects and other scene elements. You can use the Ragdoll physical description to animate the character’s Control rig for increased realism to produce a character that waves his arms as he falls. You can use the Joint physical description to create motion behavior that is inherent to objects, such as door hinges, chains, or rope.

Note On 64-bit systems, the Physics solver cannot process objects that have degenerated polygons or invalid normals. When this occurs, a warning message appears that identifies the models that have this problematic geometry, and bounding boxes are used to approximate these shapes instead. Using these bounding boxes for the joint solve may produce solve results that differ from the expected behavior. If possible, use the Cube, Capsule, or Sphere approximations to match your geometry with more precision. For more complex geometry, reconstruct your model with 3D software to avoid these non-standard geometry problems. This problem does not occur in the 32-bit version of MotionBuilder.

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