Analysis and design of the integrated controller for precise motion systems

Recently, feedforward controllers like zero phase error tracking controllers (ZPETC) and cross-coupled controllers (CCC) have been developed to effectively reduce tracking error and contouring error, respectively. This paper proposes an integrated controller which combines ZPETC and CCC to achieve both tracking and contouring accuracy. Furthermore, studies indicate that ZPETC and CCC can be designed separately in the present integrated control design. In the provided experimental setup with a servo table, an optimal ZPETC and a robust CCC based on the contouring error transfer function (CETF) were designed to achieve desirable frequency responses and stability. Experimental results show that the proposed integrated controller renders significantly improved accuracy in both tracking and contouring.