Simple PID control class for Python.

based on the C example found here: PID Controller Written in C

More details on PID loop control can be found on Wikipedia

A calculator for tuning the PID loop is available here

Usage is simple:

• Create the a PID object
  • pid = PIDController()
  • pid = PIDController(kp, ki, kd)
• Set the initial values:
  • kp - (Proportional)
  • ki - (Integral)
  • kd - (Derivative)
  • limmin - Lower limit on the output delta
  • limmax - Upper Limit on the output delta
  • tau - Lag term for the Integrator
  • T - Time is seconds
  • limMinInt - Lower limit for the Integrator
  • limMaxInt - Upper limit for the Integrator
• Loop, updating the expected (setpoint) and actual (measurement) values for a given time

  setpoint = 1.0
  
  print("Time(s)\tSystemOut\tController Out")
  t = 0.0
  while t < 4.0:
      measurement = <function for real values>(pid.out)
      pid.update(setpoint, measurement)
      print(f"{t}\t{measurement}\t{pid.out}")
      t += 0.01