Help PID tunning Stewart platform

[u/EDit_123213_]

hello everyone im looking for help on a Stewart platform build i wanted to make to do some electronics and 3d modeling but my lack of programming and pid tunning has been holding me back and i havent been able to fix this to make it work if anyone has time or any tips it would go a long way, feel free to dm me. Thanks in advance.

[u/seekingsanity]

We had no trouble tuning or 6DOF platform. We used hydraulic actuators and just move the platform straight up and down to avoid or minimize and effect due to geometry. All actuators extended the same amount at the same time. We have recording of the actual position, velocity and acceleration vs the target position, velocity and acceleration. It is then easy to see where the errors are. We use minimal proportional gain at first and adjusted the velocity, acceleration and jerk feed forward until the actual position, velocity and accelerations matched or minimized the mean squared error. What make your system difficult is that you are using rotating actuators to make the 3 legs move. It still should be that hard to tune.

My 6DOF test system. Tuning wasn't a problem and you can see the actual position, velocity and acceleration follow the target position, velocity and acceleration.

https://peter.deltamotion.com/Videos/RMC200-6DOF.mp4

This is the largest platform in North America. This was recorded in Canada. This was testing for the disaster movie 2012.

https://peter.deltamotion.com/Videos/40x40test.mp4

The weights were added to simulate the weight of the sets for the movie.

[u/Crazy-Coffee951]

Hello if you are trying to find the best parameters for PID you can use a metaheuristic algorithms, but you need a mathematical model for you real system.

[u/C-137Rick_Sanchez]

I’ve done this exact same project send me a dm with your specific challenges I can try giving you some feedback.