My background is in mechanical engineering, but I'm working on a project for which I need to design a control system for a linear actuator. I want to design the actuator using a roller screw mechanism, which in turn will be conected to a 3 horsepower electric motor through gear reduction. I need to control both the force that the linear actuator will be applying or the speed with which it it moves. I know I can use strain gauges to measure applied force and then use a PID algorithm to control it to a desired level. Also, I can use hall effect sensors attached to the motor to control speed by similar means. The problem is: the AC motor which will be used (probably something like this) needs a variable frequency drive (VFD), and I'm not familiar with those. I've used Arduino to control speed of small DC motors, but never AC motors this size. Would it be better if I use something like a PLC to accomplish this task, or do you have any other suggestions? Any hints would be helpful.