Design of digital controllers for motion control systems via model reduction

A new algorithm for the design of digital controllers is proposed. Using this approach the designer can obtain closed-loop systems with the following properties: the output will have a minimum overshoot; there will be no ripples between samples; and the output will follow the specified profile very closely. The proposed technique is somewhat similar to the design of deadbeat controllers except that pole/zero cancellation is not employed. Instead, it makes use of a new transformation for z transfer functions as well as Pade approximation in the transformed domain in order to obtain finite-impulse-response controllers of any order. As a result, the designer has greater flexibility in specifying the profile that the system has to follow