Quote:
|
Originally Posted by maxlobovsky
ok, but i thought the solution to that is to sum over a shorter period of time and use a small enough coeffecient. The integral term just becomes an additional proportional term in the code posted above when the error is large enough.
.... on second though, that isnt really a problem as the integral term isn't needed when the error is large. And i was presumptious enough to think that years of science and engineering could be faulty....  |
The PID controller is a vast simplification. It takes a while to get a handle on all the things going on and why it works, or, more importantly, doesn't work.
The best way to think of the integral term is that it, eventually, will compensate for all those unknown things that prevent you from getting to your goal (position or velocity). The problem is that if your position setpoint is moving all the time (plus & minus, typical for an arm) the integral needed going forward is precisely the wrong thing for moving in reverse! Best to just leave out.