Constrained Motion Types Defined

Constrained motion occurs when the movement possibilities of an object are restricted. Key types include:

• Completely Constrained Motion: Allows only one degree of freedom (single path).
• Incompletely Constrained Motion: Allows multiple degrees of freedom (multiple possible paths).
• Successfully Constrained Motion: Constraints enforce a specific intended path, preventing others.

Analyzing Motion Constraints Examples

We need to find the option that is NOT incompletely constrained, meaning it should be completely constrained. This analysis assumes ideal scenarios with perfect fits, which typically define specific constraint types.

Shaft Constraint in Circular Hole

A shaft with collars in a perfectly fitted circular hole:

• The hole matching the shaft diameter eliminates radial and tangential play.
• Perfectly fitted collars eliminate axial play.

This configuration restricts motion to only rotation. Therefore, it represents completely constrained motion and is NOT incompletely constrained.

Bearing Constraint for Shaft

A shaft in a perfectly designed footstep bearing:

• Prevents significant radial and axial play.
• Allows only rotation.

This is considered completely constrained motion and therefore NOT incompletely constrained.

Square Bar Constraint in Square Hole

A square bar within a perfectly fitted square hole:

• Prevents rotation and radial/tangential movement.
• Allows only translation along the bar's axis.

This represents completely constrained motion, hence it is NOT incompletely constrained.

Conclusion on Constraint Classification

Assuming perfect fits, scenarios 1, 2, and 3 all demonstrate completely constrained motion. Consequently, none of them are examples of incompletely constrained motion.

The choice 'All option are correct' signifies that options 1, 2, and 3 are all valid instances of motion that is NOT incompletely constrained. This aligns with the provided answer.