Position measurement and output feedback tracking method of hydraulic servo system based on pressure sensor

• Published in: Measurement and control (London) Vol. 58; no. 7; pp. 843 - 856
• Main Authors: Weiping, Wang, Xinyi, Zhou, Shun, Lu, Jialu, Zhang
• Format: Journal Article
• Language: English
• Published: London, England SAGE Publications 01.07.2025; Sage Publications Ltd; SAGE Publishing
• Subjects: Closed loops; Controllers; Hydraulic equipment; Hydraulics; Integrated approach; Load; Methods; Nonlinear control; Output feedback; Position measurement; Position sensing; Pressure sensors; Sensors; State observers; Systems stability; Tracking; hydraulic servo system; auxiliary variable-based observer; hydraulic accumulator; Output feedback; desired compensation
• ISSN: 0020-2940; 2051-8730
• DOI: 10.1177/00202940241277103

Instead of using position sensor, a position measurement and output feedback tracking method is proposed based on pressure sensor for a class of hydraulic servo system. First, the desired accumulator pressure is calculated and obtained in an open-loop way according to the desired cylinder position. Then, the position tracking task can be indirectly realized by achieving the pressure control. As a result, only one pressure sensor is required instead of position sensor, which is different from almost all the traditional output feedback position controller of hydraulic system. For the closed-loop pressure tracking, a desired compensation method and an auxiliary variable-based state observer are integrated to form the nonlinear controller. The theoretical and numerical simulation results demonstrate that the presented controller can attain satisfactory pressure tracking performance.