MotionDesigner Reference & User Interface > Motion Laws > Constant-Velocity : Specify Two Positions

Constant-Velocity | Two Position

The Constant-Velocity motion-law is defined by its Velocity.

In the case of a segment that is a Constant-Velocity motion-law, you can enter only its Start-Position and Start-Velocity. Its End-Position is a function of its Segment-Width.

However, it is often useful to define a Constant-Velocity by its Start Position and End-Position. In this case, you must use the Flexible-Polynomial motion-law.

Flexible-Polynomial : Two Position | Constant-Velocity

Motion-Law-2Position-CV

SEGMENT EDITOR: Control-Buttons for a 'Two Position | Constant-Velocity motion-law.

Step 1: Make sure the motion-law is a Flexible-Polynomial motion-law in the Motion-Law Selector.

Step 2: Deselect ALL 'Flow' Control-Buttons

Step 3: Deselect Start Velocity, Start Acceleration, and Start Jerk Control-Buttons

Step 4: Deselect End Velocity, End Acceleration, and End Jerk Control-Buttons

Step 5: Select the Start-Position and End Position Control-Buttons

Step 6: Enter the Start and End-Positions

Step 7: Enter the correct X-axis values.

Notes: You must enter the Velocity at the 'End of the Previous-Segment' and at the Start of the Next-Segment to make sure there is Velocity continuity in the motion.

The Acceleration and Jerk Values at the start and end of the segment are zero.

Constant-Velocity: 'Conveyor' Motion-Law

Motion-Law-2Position-CV2

SEGMENT EDITOR: Control-Buttons for a 'Two Position | Constant-Velocity motion-law.

This a single segment for one machine cycle.

The Control-Button states define the Start-Position and End-Position.

Note:

When you have a single segment and need it to be a constant velocity, you can also use a Gearing FB, and use Gearing as Ratio Ratio radio-button.

Enter 360 as the Input Pulley parameter, and the End-Position as the Output-Pulley parameter.