Performance predictable design of robust motion controllers for high-precision servo systems

A performance predictable design method of robust motion controllers for high-precision servo systems is proposed. A stabilizing control input is designed based on Lyapunov redesign for the system in the presence of uncertainty and disturbance. A robust internal-loop compensator (RIC) is proposed based on the internal model following control. Using the structural characteristics of the proposed RIC, disturbance attenuation properties and the performance of the closed-loop system determined by the variation of controller gains are analyzed. Through this analysis, in some specific applications, it is shown that if the control gain of RIC is increased by N times, the magnitude of error is reduced to its 1/N.