1. One or more non-transitory computer-readable media holding one or more executable instructions that, when executed on processing logic, tune parameters for a proportional integral derivative (PID) controller for an arbitrary nonlinear model, the media holding one or more instructions for: automatically determining a portion of the arbitrary nonlinear model to be linearized, the determination based on a desired operating point of the arbitrary nonlinear model; linearizing the determined portion of the arbitrary nonlinear model, the linearizing producing a linear model; computing an open-loop frequency response of the linear model; receiving a design specification on behalf of a user, the design specification defining: a desired gain crossover frequency for the open-loop frequency response, or a desired phase margin at the desired gain crossover frequency for the open-loop frequency response; and automatically tuning the PID controller parameters using the open-loop frequency response and the received design specification, the automatic tuning: solving algebraically at least two of a P, I, and D parameter of the PID controller for achieving a desired performance when the PID controller controls the linear model in a closed-loop.