Application of deadbeat controllers and pole placement methodologies for friction compensation in mechanical systems

Abstract

Friction is an almost unavoidable component of many mechanical systems. When not taken into account in designing control systems, the effect of friction may result in the degradation of controlled system performance. This thesis deals with the problem of designing a control system, for friction compensation in mechanical systems, via pole placement and deadbeat methodologies. Pole placement design is based on different performance measures and indices such as settling time, overshoot and ITAE. Deadbeat controller design is based on parameterization of Diophantine equations which depend on the reference signal to be tracked. System performance is analyzed on simulation level by the application of the two methodologies in a hierarchical feedback system structure, which provides both position and velocity control separately. Simulation results show that both methodologies provide acceptable performance as compared to the existing compensation schemes in literature and control performances are improved with respect to their accuracy of tracking. In addition, deadbeat controller is observed to be more promising in terms of minimum settling time.