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arXiv · 2004.00487

An Adaptive Periodic-Disturbance Observer for Periodic-Disturbance Suppression

Hisayoshi Muramatsu·Seiichiro Katsura
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Abstract

Repetitive operations are widely conducted by automatic machines in industry. Periodic disturbances induced by the repetitive operations must be compensated to achieve precise functioning. In this paper, a periodic-disturbance observer (PDOB) based on the disturbance observer (DOB) structure is proposed. The PDOB compensates a periodic disturbance including the fundamental wave and harmonics by using a time delay element. Furthermore, an adaptive PDOB is proposed for the compensation of frequency-varying periodic disturbances. An adaptive notch filter (ANF) is used in the adaptive PDOB to estimate the fundamental frequency of the periodic disturbance. Simulations compare the proposed methods with a repetitive controller (RC) and the DOB. Practical performances are validated in experiments using a multi-axis manipulator. The proposal provides a new framework based on the DOB structure to design controllers using a time delay element.

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Hisayoshi Muramatsu, Seiichiro Katsura. 2020-04-01. An Adaptive Periodic-Disturbance Observer for Periodic-Disturbance Suppression. https://doi.org/10.1109/tii.2018.2804338

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