Ultrasonic motors used in high-precision mechatronics are characterized by strong frictional effects, which are among the main problems in precision motion control. The traditional methods apply model-based nonlinear feedforward to compensate the friction, thus requiring closed-loop stability and safety constraint considerations. Implementation of these methods requires complex designed experiments. This paper introduces a systematic approach using piecewise affine models to emulate the friction effect of the motor motion. The well-known model predictive control method is employed to deal with piecewise affine models. The increased complexity of the model offers a higher tracking precision on a simpler gain scheduling scheme.
@article{arxiv.1305.6379,
title = {Robust Precision Positioning Control on Linear Ultrasonic Motor},
author = {Minh H-T Nguyen and Kok Kiong Tan and Wenyu Liang and Chek Sing Teo},
journal= {arXiv preprint arXiv:1305.6379},
year = {2013}
}