Kinematics of a Rigid Body: Basic Concepts

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Kinematics of a Rigid Body Basic Concepts

• Particle vs. Rigid body
• Planar motion vs. Spatial motion
• Type of planar motions

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Review Planar Kinematics of a Rigid Body

• 1. Particle Versus Rigid Body

Rigid body A and B may have different motions
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• 2. Planar motion vs. Spatial motion

Example 1
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Example 2
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Spatial motion - Example
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Planar motion Scientific Definition

• All particles of a rigid body move along paths
  which are equidistant from a fixed plane, the
  body is said to undergo planar motion

A body system consists of several rigid bodies.
When all rigid bodies undergo planar motion, the
system is said to undergo planar motion
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3. Types of planar motion

• Translation

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3. Types of planar motion
Rotation at a fixed axis
Planar general motion
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Types of planar motion Scientific definition

• Translation every line segment on the body
  remains parallel to its original direction during
  the motion

Rotation about a fixed axis all the particles
move along circular paths
General plane motion a combination of
translation and rotation.