Edit Flexible Polynomial Motion-Law - Basic-Level

The Flexible-Polynomial Motion-Law is good for most motion design requirements.

The purpose of this tutorial is to learn how to use the Blend-Point Controls when the segments in the motion are all Flexible-Polynomial motion-laws.

After this tutorial, you should be able to use the Blend-Point Editor to edit Flexible Polynomial segments, at a basic level.


Recommended: It is best not to mix 'Flexible Polynomial' with 'Traditional' Motion-Laws.

It is recommended [but not essential] that you use segments that are:

ALL Flexible Polynomials Motion-Laws

or

ALL Traditional [also called 'Standard'] Motion-Laws

Video of this Tutorial

How to...Edit a Motion with Flexible-Polynomial Segments.

tog_minus        Important information to remember

The Blend-Point Editor can EDIT ONLY the:

Start of the RED Selected-Segment.
End of the Previous-Segment.

You cannot edit the:

End of the Red Selected-Segment

To edit the end of the Selected-Segment, you muse click the 'Next-Segment'.

As soon as you click the 'Next-Segment', it becomes the Selected-Segment!

tog_minus        The Default Motion has four Flexible Polynomial Segments

MotionGraphs-PVA

Number of Segments:

Four segments

Motion-Width (X-axis):

360º

Motion-Laws

All four segments are Flexible-Polynomial

Note: Only the bottom graph displays the X-axis values. All the motion-derivatives [P.V.A.J.] use the same X-axis values.


Make the second Blend-Point the Active-Blend-Point.

STEP 1.Click above or below the graph line of the second segment.

The second segment3s becomes the RED Selected-Segment. The Blend-Point1s-red at its start, has a RED [orange in image]

Terminology:

1s-b Active-Blend-Point: The Blend-Point at the left-side of the RED selected Segment, with the RED [or orange] around it.

2-R-RED-15 Previous-Segment: This is the segment before (earlier than) the RED Selected-Segment, and the Active-Blend-Point.

3-R-RED-15 Selected-Segment: This is the RED segment.

You can look at the Motion-Law Selector to confirm that the RED Selected-Segment is a Flexible-Polynomial.

tog_minus        Edit the X-axis Value of Blend-Point #2

Open Blend-Point Editor icon

Open Blend-Point Editor icon

STEP 1.Open the Blend-Point Editor.

Click the Blend-Point and Segment toolbar > Edit Blend-Point icon

 

STEP 2.Edit the X-axis value of the active Blend-Point.

In the Blend-Point Editor - see image below - you can see two Orange Separators.

You edit the X-axis value of a Blend-Point in the X-axis Values separator.

You move the Blend-Point to the left or the right as you edit the X-axis parameter in the data box.

The Blend-Point 'slides' across the motion, so that the Motion-Width does not change.

The X-axis value in the Blend-Point Editor and the X-axis value of the Blend-Point motion graph.

The X-axis value in the Blend-Point Editor and the X-axis value of the Blend-Point motion graph.

The image shows the virtual connection between the X-axis value in the Blend-Point Editorand the Blend-Point position along the X-axis in the motion-graph area.

tog_minus        Edit the Y-Value Position of Blend-Point #2

Edit Position of Blend-Point

Edit Position of Blend-Point

STEP 2.Edit the Y-axis motion-values of the active-Blend-Point.

In the Blend-Point Editor -you will see you can edit the Position Values.

This is where - in the Position Graph - the Blend-Point is at the start of the Selected-Segment.

To move the Blend Segment up or down, that is to edit the Position of the Blend-Point, you must edit the Position value in the data box.

STEP 3.Change the Position Value of the Blend-Point to 70º

Use the spin-box, to edit the Position Value from 90º to 70º

Control Buttons in the Blend-Point Editor.

1s-b Y-axis Values separator

2-R-RED-15 End Position Control-Button and the End Position data box are active .

Thus, we can edit its value. It controls the Position at the end the Previous-Segment.

3-R-RED-15 The Match Control Button is 'active'.

Because the Match Control Button is active, the Start Position4-R-RED-15 of the RED Selected-Segment is forced to be equal to the 'End-Position' of the Previous-Segment ; the Start-Position value is Read-Only.

 

With the Flexible Polynomial Motion-Law, the Match Control-Buttons are available for each Motion-Derivative:

When the Match-Control Button of a motion-derivative is active, the motion-value of the motion-derivative at the ...

... Start of the RED Selected-Segment ...

... is forced to become equal to the ...

... End of the Previous-Segment.

tog_minus        Edit the Velocity Y-Value of Blend-Point No2

Edit Velocity motion-values of Blend-Point

Edit Velocity of Blend-Point

In the Blend-Point Editor

1s-b Y-axis Values separator

2-R-RED-15 End Velocity data box [Velocity at end the Previous-Segment.

3-R-RED-15 The Match Control Button is 'active'.

When the Match Control Button is active, the Start Velocity4-R-RED-15 of the RED Selected-Segment is forced to be equal to the 'End-Velocity' of the Previous-Segment ;

The Start-Velocity value is Read-Only.

STEP 4.Change the End Velocity to 200º/s

Use your mouse to click on the left or right spin box button at the right-side of the End Velocity box2-R-RED-15.

You can see in the velocity motion-graph that the:

Velocity increases to 2005-R-RED-15.

tog_minus        Edit the Acceleration Y-Values of Blend-Point No2

Tut2-YAccControl

In the Blend-Point Editor

1s-b Y-axis Values  separator

2-R-RED-15 End Acceleration data box [Acceleration at the end of the Previous-Segment]

3-R-RED-15 The Match Control Button is 'active'.

When the Match Control Button is active, the Start Acceleration4-R-RED-15 of the RED Selected-Segment is forced to be equal to the 'End-Acceleration' of the Previous-Segment ;

The Start-Acceleration value is Read-Only.

STEP 4.Change the End Acceleration to -4000º/s2

Use your mouse to click on the left or right spin box button at the right-side of the End Acceleration box2-R-RED-15.

You can see in the acceleration motion-graph that the:

Acceleration changes to -40005-R-RED-15.

Tutorial and Reference Help Files for MechDesigner and MotionDesigner 13.2 + © Machine, Mechanism, Motion and Cam Design Software by PSMotion Ltd