Good Day, I have the task of rerofitting an AC inverter that controls the long travel on a crane at a shipping terminal which has built in software to prevent swaying of the load automatically. It is operator driven and this control is to compensate for operator short falls. The only feedback that I have from the system is the rope length in the form of a 4-20mA signal. The rest of the signals are operator driven like the speed reference from the joystick and the stop/run signals. What would be the best way to approach this type of control?