[dellagd]

It seems what you described is not PID control, but more simply just P control, which will most likely not get to a set point on an elevator that would fall by gravity if the motor was sent a zero voltage.

The I value of PID will allow the controller to accumulate the error over time, such that the longer the elevator is away from its set point, the more error that will accumulate, and the harder the controller will consequently drive the motor to get to said setpoint. With more load, the I value will take longer to accumulate the error required, so it probably wouldn't reach the set point as fast, but regardless of weight, it should lift it fully, as long as the elevator is physically capable of it.

As the elevator is at its set point, this I value persists (unless intentionally reset), and will hold your elevator at that point. If you do this though, be careful about it, as you are stalling the motors, which is pretty bad unless you're using something sealed like a CIM (and you're careful about it).


However, more of the code would help, such as for the elevator itself and what class contains the setSetpoint() method so we can all see how you define the PID controller.