Shape-based Feedforward Tuning
Shape-based Tuning has been broken up into four main sections:
Before You Start
You will need to tune the closed loop parameters (PID or PIV or etc.) before tuning the feedforwards. The closed loop tuning does not need to be perfect, but you will need to make several aggressive moves to optimize your feedforward coefficients.
Before attempting to turn the servo with Shape-based Feedforward Tuning, you will need to properly set up Motion Scope so that you can evaluate the motion with the appropriate data. You can easily designate which traces you wish to include on the motion plots by clicking the "Traces" button and selecting the following traces:
It is also important to read the changes in position error from one trial to the next. In Motion Console, turn off auto scaling on the position error trace by clearing the "During Acquire" and "During Display" options under Traces Edit.
A Trust TA 9000 will be used for the following examples, unless otherwise noted (www.trustautomation.com).
What is a good starting move?
Which feedforward term do I start with?
For all the shape-based tuning examples, the integral
will be set to zero (Ki = 0).
For more information about the different types of shape based tuning, please see the following sections:
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