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arXiv · 1305.6379

Robust Precision Positioning Control on Linear Ultrasonic Motor

Minh H-T Nguyen·Kok Kiong Tan·Wenyu Liang·Chek Sing Teo
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Abstract

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.

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Minh H-T Nguyen, Kok Kiong Tan, Wenyu Liang, Chek Sing Teo. 2013-05-28. Robust Precision Positioning Control on Linear Ultrasonic Motor. https://arxiv.org/abs/1305.6379

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