Constant-Velocity : is a 'Polynomial' Motion-Law.
Segment-Editor AND Blend-Point Editor
CAN specify the:
• | Position at the START of the segment. |
• | Velocity at the START of the segment. |
The Position and Velocity motion-values usually flow from the START of the Previous-Segment, especially when it is Flexible-Polynomial motion-law.
CANNOT specify the:
• | Velocity at the END of the segment, because the Velocity at the END must EQUAL the Velocity at the START of the segment! |
• | Position at the END of the segment... |
...the Position at the end of the Constant-Velocity segment is a function of the:
o | Position at the START of the segment |
o | Velocity at the START of the segment |
SEGMENT-EDITOR: Control Buttons to specify the Constant-Velocity segment
VELOCITY DIS-CONTINUITY
'Discontinuity' means we allow a 'step' in the Velocity graph. This puts a 'kink' In the Position graph.
1. | Click the Constant-Velocity segment to make it the RED Selected-Segment |
|
Open the Segment-Editor
|

|
2. | De-select the Velocity 'Match' [Flow] Control-Button at the left of the Velocity motion-derivative |
|

|
3. | Make sure the 'Edit Start' Control Button is active, to the left of the 'Start Velocity' motion-value |
|
![^^ SEGMENT-EDITOR: Control Buttons to give a 'DIS-CONTINUITY [STEP] in Velocity with the CONSTANT-VELOCITY motion-law^^ ^^ SEGMENT-EDITOR: Control Buttons to give a 'DIS-CONTINUITY [STEP] in Velocity with the CONSTANT-VELOCITY motion-law^^](se-constantvelocitynomatch.png) ^^ SEGMENT-EDITOR: Control Buttons to give a 'DIS-CONTINUITY [STEP] in Velocity with the CONSTANT-VELOCITY motion-law^^
|
4. | Enter a value in the 'Start Velocity' data box. [see below, 1,480 as an example] |
|
VELOCITY CONTINUITY
1. | Click the Constant-Velocity segment to make it the RED Selected-Segment |
|
In the Segment-Editor
|

|
2. | Select the 'Match' [Flow] Control-Button at the left side of the Velocity Control |
|
See below: Segment Editor Control-Buttons for the Constant-Velocity Segment with 'flow'
The Start-Velocity Control Button becomes write-only because:
• | the Velocity at the Start of the Selected-Segment is specified by the Velocity at the end of the Previous-Segment. |
The Edit End Control Button becomes write-only because:
• | the Velocity at the End of the Selected-Segment is equal to the Velocity at the start because it is defined as a 'Constant-Velocity' motion-law. |
|
 Segment Editor: Control-Buttons for the CONSTANT-VELOCITY segment with 'flow'
|

|
In the Segment-Editor:
3. | Click the 'Previous' button to make the Previous-Segment become the Selected-Segment. |
|
The Previous-Segment now becomes the Selected-Segment[!]. In this motion, the Previous-Segment happens to be a 'Flexible-Polynomial' motion-law. Thus, you can specify its Velocity at its end: its End-Velocity
4. | Enter a value in the 'End-Velocity' data box. [see below, 1,380 in this example]. |
The End-Velocity of this segment 'flows' to the Next-Segment, which is the Constant-Velocity segment.
|
 Segment-Editor: Flexible-Polynomial Segment and the 'PREVIOUS-SEGMENT' that 'flows' to the CONSTANT-VELOCITY segment.
|
See also: Tutorial 3: Constant-Velocity with Flexible-Polynomial
|

|
Example in image:
The Velocity of the Constant-Velocity Segment is 1380 º/sec.
The Previous-Segment and the Next-Segment are Flexible-Polynomial Motion-Laws.
Application Notes:
For example, a transfer mechanism that makes a transfer to a belt moving at Constant-Velocity.
'On-the-fly' cutting, printing, filling, labeling machines.
|