Motion-Law: Constant-Velocity

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Motion-Law: Constant-Velocity

Constant-Velocity Cam-Law, Motion-Law

This is a Polynomial motion type

See also : Constant-Velocity: Specify Two Positions.

Motion-Values:

You CAN specify its:

Start-Position

The Start-Position usually flows from the End-Position of the Previous-Segment  

Start-Velocity

The Start-Velocity usually flows from the End-Velocity of the Previous-Segment

You CANNOT specify its:

End-Position

End-Velocity

End-Acceleration or End-Jerk


The End-Position is a calculated from the:

oStart-Position,

oStart-Velocity, and

oSegment-Width

Then End-Velocity is (obviously) equal to its Start-Velocity


Example

VELOCITY DIS-CONTINUITY

Definition of discontinuity: the derivative of the motion-derivative changes instantly, There is an instant change of the motion-value for the motion-derivative.

A step-change in Velocity is not recommended, of course.

A discontinuity in Velocity is also infinite acceleration - mechanically impossible.

A step-change puts a kink in the Position graph.

It is here as an example.

1.Use the Motion-Law Selector to change a motion-law of a segment to a Constant-Velocity.

2.Click above or below the segment in the motion-graphs.

The Constant-Velocity segment is now the Selected-Segment.

3.Open the Blend-Point Editor

MT-BPE-CB-DoNotFlow

4.Set the Match Control-Button to Do Not Match

5.Enter a Start-Velocity value that is not equal to the End-Velocity value.

Blend-Point Editor: Velocities at Blend-Point are not Equal

Blend-Point Editor: Velocities at Blend-Point are not Equal

Step in Velocity Graph, & Kink(corner) in Position Graph. Step in gradient at Blend-Point in Position-Graph.

Step in Velocity Graph, & Kink(corner) in Position Graph.
Step in gradient at Blend-Point in Position-Graph.

Example continued...

Velocity Continued.

1.Use the Motion-Law Selector to change a motion-law of a segment to a Constant-Velocity.

2.Click above or below the segment in the motion-graphs.

The Constant-Velocity segment is now the Selected-Segment.

3.Open the Blend-Point Editor

MT-BPE-CB-DoFlow

1.Set the Match Control Button to Do Flow / Do Match - see image

Blend-Point Editor: Velocity Equal at Blend-Point.

Blend-Point Editor: Velocity Equal at Blend-Point.

Smooth Flow of Velocity at Blend-Point Equal Gradients of Position Graph at Blend-Point

Smooth Flow of Velocity at Blend-Point
Equal Gradients of Position Graph at Blend-Point