Robust nonlinear position control with extended state observer for single-rod electro-hydrostatic actuator
- Authors
- Son, Y.S.; Kim, W.
- Issue Date
- Oct-2021
- Publisher
- MDPI
- Keywords
- Electro-hydrostatic actuator; Position control; Position measurement; State estimation
- Citation
- Mathematics, v.9, no.19
- Journal Title
- Mathematics
- Volume
- 9
- Number
- 19
- URI
- https://scholarworks.bwise.kr/cau/handle/2019.sw.cau/50218
- DOI
- 10.3390/math9192397
- ISSN
- 2227-7390
2227-7390
- Abstract
- In the existing literature, studies on position controller design using only position feedback, considering the disturbances for single-rod electro-hydrostatic actuators (EHAs), have not been re-ported. Herein, we propose a robust nonlinear position control with an extended state observer (ESO) for single-rod EHAs. A new EHA model that consists of position, velocity, and acceleration with an internal state variable is developed. Instead of the separated port pressure dynamics, the acceleration dynamics were defined. The external disturbance, model, and input function uncertainties were lumped into a disturbance. An ESO is developed to estimate the disturbance, as well as the position, velocity, and acceleration. In practice, it is difficult to accurately estimate the disturbance because it includes the external disturbance, system dynamics, and input function uncertainty. The poor estimation performance may degrade the position tracking performance, but a high gain cannot be used to suppress the estimation error because of the measurement noise amplification. To resolve this problem, a robust nonlinear position controller is developed via a backstepping procedure. In the controller, a nonlinear gain is implemented to sufficiently suppress position tracking without the use of a high gain. The stability of the closed-loop system is mathematically proven using the input-to-state stability. The proposed method is simple and suitable for real-time control. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.
- Files in This Item
-
- Appears in
Collections - College of Engineering > School of Energy System Engineering > 1. Journal Articles
Items in ScholarWorks are protected by copyright, with all rights reserved, unless otherwise indicated.