> Dynamics

>  Lesson 2:  Rigid bodies and constraints

# Introduction

In Maya, a rigid body is a surface which has the attributes of an unyielding shape. Unlike conventional computer surfaces, rigid bodies collide rather than pass through each other during animation and are used for creating dynamic simulations. As well, rigid surfaces do not deform when they collide with other objects in Maya.

Rigid bodies can be created from polygonal or NURBS surfaces. Rigid body attributes can be assigned to the surfaces so they act and react in a simulation in specific ways. Examples of rigid body attributes are velocity, mass, and bounce.

To animate rigid body motion, you can use fields, keyframes, expressions, rigid body constraints, or collisions with particles or other rigid bodies.

Rigid body constraints restrict the motion of rigid bodies. The constraints simulate the behavior of real-world items you’re familiar with, such as pins, nails, barriers, hinges, and springs.

In this lesson, you use create a rigid body dynamic simulation in which you drop a ball on some planks and watch the simulation in action. In this lesson you learn how to:

• Create objects with physical properties.
• Apply hinge constraints to objects so they react in specific ways.
• Set attributes for the rigid bodies to be either active or passive for the simulation.
• Play back a rigid body dynamic simulation.

rigidBody.mov