We actually did this with a quadcopter for my undergrad capstone project. It had a tendency to wildly flail about so we had to go to the indoor basketball court/gym when no one else was there. It took a couple of weeks, but we got it working pretty well and developed and entire system for the quadcopter to take off, track/follow, and land on a moving RC car. Fun times!
True to that, but this tool hopes to provide an educated initial guess.
Watch your device whirr and attempt to jump off your table as your algorithm is trying to optimize the P factor! Quickly estimate how good the fit is just by looking at the actuator!
(Disclaimer: think hard about safety before doing this, and make sure your device is strong enough or your motor is weak enough to ensure that no parts will be flying into people)