High-Precision Tracking of Periodic Signals: A Macro-Micro Approach With Quantized Feedback

• Published in: IEEE transactions on industrial electronics (1982) Vol. 69; no. 8; pp. 8325 - 8334
• Main Authors: Salton, Aurelio T., Zheng, Jinchuan, Flores, Jeferson Vieira, Fu, Minyue
• Format: Journal Article
• Language: English
• Published: New York IEEE 01-08-2022; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Actuators; Asymptotic properties; Bandwidth; Coders; Control design; Dual-stage actuator; Error analysis; Feedback; Feedforward systems; Harmonic analysis; macro–micro; Measurement; Microactuators; motion control; periodic signals; quantization; Quantization (signal); Tracking; Tracking errors
• ISSN: 0278-0046; 1557-9948
• DOI: 10.1109/TIE.2021.3109511

This article proposes a novel control design method for high-precision positioning systems. The method aims to eliminate the tracking error caused by measurement quantization present in positioning systems with incremental encoders. By employing a combined internal model based feedback and quantized feedforward design, we are able to make the output of the positioning system asymptotically track any input signal with one or more sinusoidal components of known frequencies and a possible constant component. When combined with a micro-actuator, the resulting dual-stage positioning system is able to track any continuous periodic signal with a known period. Besides theoretical guarantees, the proposed design is validated experimentally and proved able to achieve asymptotic tracking error below <inline-formula><tex-math notation="LaTeX">\pm \text{1}\ \mu</tex-math></inline-formula>m when subject to a sensor quantization level of 5 <inline-formula><tex-math notation="LaTeX">\mu</tex-math></inline-formula>m.