Design of acceleration/deceleration profiles in motion control based on digital FIR filters

Abstract

In motion control, the reference commands should pass through the acceleration/deceleration (Acc/Dec) processor before being fed into the servo loop. Consequently, not only can a smooth motion profile be obtained but undesirable vibration can be avoided. In this study, we develop a systematic design procedure for the Acc/Dec processor based on the discrete time finite-impulse-response (FIR) filter design technique with some necessary conditions. Compared with the conventional Acc/Dec scheme, the FIR Acc/Dec scheme poses the advantage that the contouring error can be analyzed. Also, the contouring error caused by the conventional Acc/Dec scheme is evaluated by demonstrating a mapping technique from the conventional Acc/Dec scheme to the FIR Acc/Dec scheme. The proposed Acc/Dec algorithm is quite flexible and efficient, creating space for users to use more sophisticated profiles to more efficiently match the system constraints with minimum contouring errors. Simulation and experimental results verify that the proposed Acc/Dec processor can effectively improve the motion accuracy. (C) 1998 Elsevier Science Ltd. All rights reserved.