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ROBOTIS-GIT / DynamixelSDK

ROBOTIS Dynamixel SDK (Protocol1.0/2.0)
http://emanual.robotis.com/docs/en/software/dynamixel/dynamixel_sdk/overview/
Apache License 2.0
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Position Controller Feedforward Calculation #571

Open mrunaljsarvaiya opened 2 years ago

mrunaljsarvaiya commented 2 years ago

For a XM540 in position controller mode, could I get an explanation of how the first feedforward term is calculated (Referring to the block diagram at 2.4.25 at https://emanual.robotis.com/docs/en/dxl/x/xl430-w250/)? Is the feedforward based on the present motor position and goal position or does it use the previous goal position and the new incoming goal position to calculate a feedforward velocity?

ROBOTIS-David commented 2 years ago

As the image describes, the Feedforward refers to the generated profiles (Velocity Trajectory(136), Position Trajectory(140))

image

Thinking of what you are inquirying, you are looking the way of finding proper gains by referencing other data, I guess.

Make sure that internal controller gains should be determined by using experiment approach.

See - DYNAMIXEL Tips | DYNAMIXEL Position Controller PID Gain Tuning (feat. Arduino example)