Observability of the performance evaluating area and optimized robust control of an ultra-precision stage

An optimized robust control is presented for an ultra-precision stage. The concept of performance evaluating area is used in the cost function in the optimizing specification. To obtain the information of performance evaluating area, the observability analysis is introduced after lumped parameter modeling of the stage. A standard PID controller is used and its robustness is discussed with sensitivity function. Advantage of the optimized parameter is shown in the result of simulation.