The computer-aided design of a servo system as a multiple-criteria decision problem

This paper treats the selection of controller gains of a servo system as a multiple-criteria decision problem. In contrast to the usual optimization-based approaches to computer-aided design, inequality constraints are included in the problem as unconstrained objectives. This considerably simplifies the optimization problem when the constraints are imposed on the trajectories of a dynamic system. The objectives are evaluated by a simulation of the step response of the servo system over time. For the multiobjective optimization the DIDASS/N software package is used which can easily be linked with simulation software. The approach is promising for relatively small problems (up to ten objectives) as they appear in computer-aided design in (control) engineerin