"If you zero the gains (or don't write the code for) the integral part, which slowly closes the error over a period of time, and the derivative part, which smooths out the operation, that's exactly what this does."

"I think you're missing how a proportion-derivative-integral (PID) controller works, what the inputs are to this particular controller, and how those input are driven by the system and the environment.  The wind and water current will push the USV…"

"Linked are a couple of papers from Florida Atlantic University that present a station keeping PID controller that uses GPS and heading sensor inputs.  They were tested off-shore in the Gulf Stream in small craft with good results.  Looks simple to…"