Efficient autonomous feedback controller parameter design considering robust stability for galvanometer scanner

Robust stable feedback (FB) controller design against plant perturbation is crucial for industrial servo systems. However, since the controller parameter design generally requires expert skills and/or considerable labor by engineers, an autonomous controller design technology would be promising. This paper presents an efficient autonomous design method that optimizes the parameters of a cascade structure FB controller to achieve robust stabilization. Conventionally, robust stabilization is realized by imposing stability constraints on all the perturbed plant model sets in a parameter optimization problem. As a result, the design time would be much longer owing to the complicated optimization problem. The proposed method makes the parameter optimization considering robust stability more efficient than the conventional method, by simplifying the stability constraint definition and optimizing the specified circle radius for the stability constraint based on a bisection method. The effectiveness of the proposed method is evaluated through an example FB controller design for a laboratory galvanometer scanner.