A snippet illustrating 20% and 30% PWM as well as the hardware emergency stop switch

PWMsnippet.py

def decide(sensors, cycle, lastCommand):
  if sensors.userCommand == Commands.NONE:           #no changes to input
    sensors.userCommand = lastCommand
  if sensors.frontBumper:                            # hardware stop triggered so stop regardless of user's opinion
    newState = State(Commands.STOP)
  elif sensors.userCommand == Commands.FORWARD_slow:
    if cycle in [3,8]:                               # slow is 20% duty cycle
      newState = State(Commands.FORWARD_full)
    else:
      newState = State(Commands.STOP)
  elif sensors.userCommand == Commands.FORWARD_medium:
    if cycle in [3,6,9]:                             # medium is 30% duty cycle
      newState = State(Commands.STOP)
    else:
      newState = State(Commands.FORWARD_full)
  else:
    newState = State(sensors.userCommand)
  return newState