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A blend is similar to a normal start, but allows a move to be synchronized and/or combined with the move that immediately precedes it. It has the same requirements for valid trajectory parameters as the Start Motion VI. The blended move uses the most recently loaded values of acceleration, velocity, target position, s-curve, operation mode, and so on to generate the motion profile.
If a stepper axis is in a killed state (not energized), halt the axis using the Stop Motion VI--with Stop Type set to halt stop--before you execute a Start Motion or Blend Motion VI. After you halt the axis, you might need to wait before executing a Start Motion or Blend Motion VI so that the stepper drive comes out of the reset state. If the stepper drive does not come out of the reset state before you execute the VI, the stepper axis might lose some steps during acceleration. To determine whether you need to wait before executing the VI, refer to your stepper drive documentation or contact the drive vendor.
The primary difference between a Start Motion VI and a Blend Motion VI is that the Start Motion VI is immediate and preemptive, while the Blend Motion VI waits and starts the next move upon the completion of the previous move.
Blending smoothly blends two move segments on an axis, axes, or vector space(s). There are three types of blends, controlled by the blend factor:
For sequencing multiple moves with blends, FlexMotion must complete one blend before parameters for the next move are loaded.
If motion on any axis involved in a blend is illegal due to a limit or other error condition, the entire Blend Motion VI is not executed and a modal error is generated. None of the axes are affected, and the move(s) in process complete normally and stop.
Below are some examples of how to use the blend function with your software.
Example 1
To blend motion on axis 4 only, call the Blend Motion VI with the following parameters:
Axis or Vector Space = 4
Axis/VS Map = don’t care
Example 2
To blend motion on vector spaces 2 and 3, call the Blend Motion VI with the following parameters:
Axis or Vector Space = 0x10
Axis/VS Map corresponds to the following.
Axis/VS1 False
Axis/VS 2 True
Axis/VS 3 True
Axis/VS 4 False
Axis/VS 5 False
Axis/VS 6 False
Related Links:
FlexMotion Software Reference Manual
If a stepper axis is in a killed state (not energized), halt the axis using the Stop Motion VI--with Stop Type set to halt stop--before you execute a Start Motion or Blend Motion VI. After you halt the axis, you might need to wait before executing a Start Motion or Blend Motion VI so that the stepper drive comes out of the reset state. If the stepper drive does not come out of the reset state before you execute the VI, the stepper axis might lose some steps during acceleration. To determine whether you need to wait before executing the VI, refer to your stepper drive documentation or contact the drive vendor.
The primary difference between a Start Motion VI and a Blend Motion VI is that the Start Motion VI is immediate and preemptive, while the Blend Motion VI waits and starts the next move upon the completion of the previous move.
Blending smoothly blends two move segments on an axis, axes, or vector space(s). There are three types of blends, controlled by the blend factor:
- Blend moves by superimposing the deceleration profile of the previous move with the acceleration profile of the next move (blend factor =-1).
- Blend moves by starting the next move at the exact point when the previous move has stopped (blend factor = 0).
- Start the next move after a programmed delay time between the end of the previous move and the start of the next move (blend factor > 0 ms).
For sequencing multiple moves with blends, FlexMotion must complete one blend before parameters for the next move are loaded.
If motion on any axis involved in a blend is illegal due to a limit or other error condition, the entire Blend Motion VI is not executed and a modal error is generated. None of the axes are affected, and the move(s) in process complete normally and stop.
Below are some examples of how to use the blend function with your software.
Example 1
To blend motion on axis 4 only, call the Blend Motion VI with the following parameters:
Axis or Vector Space = 4
Axis/VS Map = don’t care
Example 2
To blend motion on vector spaces 2 and 3, call the Blend Motion VI with the following parameters:
Axis or Vector Space = 0x10
Axis/VS Map corresponds to the following.
Axis/VS1 False
Axis/VS 2 True
Axis/VS 3 True
Axis/VS 4 False
Axis/VS 5 False
Axis/VS 6 False
Related Links:
FlexMotion Software Reference Manual
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