<< Click to Display Table of Contents >> Navigation: Getting Started Tutorials - MotionDesigner > Tutorial 5: Edit the Start of Traditional Motion-Law |
With a Traditional Motion-Law you can specify the Start-Position and End-Position.
You CANNOT (usually) edit the Velocity, Acceleration, or Jerk at the Start and End of the Traditional Motion-Law.
The velocity and acceleration values are usually zero at the Start and End of a Traditional Motion-Law.
See Standard or Traditional Segments
In this Tutorial, we show you how to edit the Start-Position of a Traditional Motion-Law.
We cannot edit the Velocity, Acceleration or Jerk values at their Start or their End, They are defined by the mathematical definition of the Traditional Motion-Law.
We consider the two cases:
How to edit the position at the start of a Traditional Motion-Law when:
Case 1: The motion-law of the Previous-Segment is a Traditional Motion-Law.
Case 2: The motion-law of the Previous-Segment is a Dwell Motion-Law.
VIDEO
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In the image above, the:
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![]() Start Blend-Point Editor |
To edit the Position at the End of the Modified-Sinusoid - when it is also the Position at the Start of the Modified-Trapezoid Motion-Law 1.Click the Modified-Trapezoid segment 2.Click the Blend-Point and Segment toolbar > Start Blend-Point Editor icon |
![]() Position Values in the Blend-Point Editor |
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In Y-axis Values of the Blend-Point Editor (see image above) 3.Make sure the Specify End Position Control-Button is active 4.Make sure the Match Control-Button is active 5.Edit the End-Position The End-Position value is the position at the end of the Modified-Sinusoid Segment CASE 1 is easy and the normal case. |
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Question: Why are the Velocity, Acceleration, and Jerk Control Buttons disabled? Answer: You cannot edit them. The motion-derivatives are defined by the mathematical function for the Modified-Sinusoid and Modified-Trapezoid segments. The Velocity and Acceleration values are zero - by definition of the Mathematical Function - the Motion-Law. |
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In the image above, the:
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![]() Start Blend-Point Editor |
To edit the Position at the End of the Dwell - when it is the Position at the Start of the Modified-Trapezoid 1.Click the Modified-Trapezoid Segment 2.Click the Blend-Point and Segment toolbar > Start Blend-Point Editor icon |
![]() Blend-Point Editor Y-axis Position Values |
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In the Y-axis Values separator of the Blend-Point Editor : The End-Position Control-Button Thus you cannot enter a value in the data boxes ! First Remember: Start-Position = Start of the Selected-Segment (the Modified-Trapezoid) End-Position = End of the Previous-Segment (the Dwell) Why are they READ-ONLY? |
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Definition 1 : |
DWELL: Position at End of Dwell = Position at the Start of Dwell |
Rule 1 : |
Dwell: You must edit the Start-position of the DWELL Segment |
Rule 1: Select the Dwell segment 3.Click the Previous-Segment icon in the Blend-Point Editor. |
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![]() Blend-Point Editor Y-axis Position Values |
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The Dwell Segment is now the Selected-Segment. We cannot edit its Start-Position Again, why? a MotionDesigner Rule: |
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Rule 2 : |
If the Match Control-Button ... you must edit the end-Position of the Previous-Segment (to the Dwell-Segment) |
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Rule 2 : 4.Use the Spin-Box (or enter a value with your keyboard) to edit the End-Position In the image below, the End-Position=100 Notice : Start-Position This is because the Match Control-Button |
![]() Blend-Point Editor Y-axis Position Values |
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SUMMARY: How you must edit the Start of a Traditional Motion-Law when the Previous Segment is a Dwell. Select the Dwell Segment ... ... edit the End-Position of the Previous-Segment to the Dwell ... automatically, the End-Position of the Dwell Segment = Start-Position of the Dwell Segment (see Definition 1 of DWELL: End-Position=Start-Position) ... automatically, the Start-Position of the Modified-Traditional segment = End-Position of the Dwell Segment Note: The above statements are with Match-Control Buttons = active. |