DC and Quasi-DC Acceleration Observation for Servosystems with Piezoelectric Accelerometers

具有壓電式加速規的伺服系統直流與準直流加速度觀測

呂有勝(Yu-Sheng Lu) ； 李柏辰(Po-Chen Lee)

《中國機械工程學刊》 43卷5期 (2022/10) Pp. 421-429

摘要

This paper presents two observers, which combine a piezoelectric accelerometer with a positional sensor that commonly exists in a servo system. The piezoelectric accelerometers have wide measurement bandwidth but cannot measure an acceleration's dc and quasi-dc components. The proposed observers can estimate dc and quasi-dc components of an acceleration, avoiding the piezoelectric accelerometers' drawback. In contrast to commonly used capacitive accelerometers, the proposed observers can produce wide dynamic bandwidth owing to the use of a piezoelectric accelerometer. Compared with existing acceleration observers, the proposed observers do not require a plant's model and are thus completely insensitive to model uncertainties. Moreover, the proposed observers do not directly differentiate the positional signal twice with respect to time and are thus more immune to positional sensor noise. The proposed observers are experimentally applied to a linear motion stage to investigate applicability and feasibility of the proposed schemes.

關鍵字

acceleration ； observer ； piezoelectric accelerometer ； servo system

並列摘要

本文介紹了兩個觀測器，它們融合了壓電式加速規（piezoelectric accelerometer）與經常存在於伺服系統中的位置感測器。壓電式加速規具有高的測量頻寬，但無法測量直流和準直流加速度。本文所提出的觀測器可以估測直流和準直流加速度，避免壓電式加速規的缺點。與現有的加速度觀測器相比，本文所提出的觀測器不需要受控體的模型，因此對於受控體模型的不確定性完全不敏感。此外，本文所提出的觀測器不會直接將位置訊號微分兩次，因此對於位置訊號的高頻雜訊較不敏感。透過將所提出的觀測器應用於線性運動平台，本文以實驗方式驗證其適用性和可行性。