Rigid-Body Motion

 

Definitions

• Kinematics: The study of a body's motion without regard to its mass or applied forces.
• Rigid Body: A rigid body has size and may rotate as well as translate.

 

Types of motion

• Pure translation: A body only translates with no rotation.
• Pure rotation: A body rotates about a fixed axis.
• General planar motion: A body rotates and translates.

 

Motion characteristics

• Angular position: (θ) Angular position relative to an inertial coordinate axis. Similar to how θ was measured in polar coordinates.
• Angular velocity: (ω) How fast a body is rotating.
• Angular acceleration: (α) How fast a body's rotation rate is increasing or decreasing.