Abstract
In this paper, we have developed an analysis and synthesis method for mixed-sensitivity problems in sampled-data positioning control systems. To avoid complicated calculations, this method uses frequency responses of the controlled object and the digital controller for calculating the characteristics of the control system. This paper shows relationships between the sensitivity function and complementary sensitivity function for the mixed sensitivity problem in a sampled-data positioning control system. This paper also addresses the mixed sensitivity for multi-rate control systems that include an interpolator, a multi-rate filter, and a multi-rate hold. Simulations and experiments conducted on the sampled-data positioning control system of a head-positioning control system in a hard disk drive verify the validity of the proposed method.
