PID inconsistency
I am tuning my PID controller for each joint of a manipulator. I tuned a prismatic joint and made sure that I set P, I and D that gives no steady state errors. When I change the .yaml file with the new PID values and give the same step reference like that done during tuning, the response is different than what I got before and I have a steady state error. Why is this? I haven't changed anything from the model such as weight etc.
I think that you should ask this at https://robotics.stackexchange.com/ instead. Unless you can update your question with more information, this appears to be a question about robotics in general and not ROS-related.