Improved extended state observer-based global sliding-mode finite-time control for displacement tracking of a hydraulic roofbolter

Abstract

The dead-zone nonlinearity and uncertain dynamics inevitably weaken the tracking performance of the displacement system for a hydraulic roofbolter. To address the above problem, this paper proposes a global slidingmode controller based on a reduced-order PD-type extended state observer (GSMC-PDESO). Firstly, the displacement system model of a hydraulic roofbolter is built by using a compensation technique to suppress the effect of dead-zone nonlinearity on control performance. Following that, a novel extended state observer that has less dimensions and few gains than standard one, called reduced-order PD-type extended state observer, is designed, with the purpose of improving the estimation performance and suppressing noise amplification. Moreover, a global sliding mode unit mainly composed of a novel global integral sliding-mode surface (NGISMS) and a novel global sliding-mode control law (NGSMCL) is developed, which aims to improve global robustness, eliminate the chattering and adverse impact on estimation error of disturbances, as well as provide an effective and continuous control law. By comparing the proposed GSMC-PDESO with ten control methods, the comparative experimental results verify the effectiveness of the proposed GSMC-PDESO and strategies.

Adaptive Sliding Mode Control of an Electro-Hydraulic Actuator With a Kalman Extended State Observer

“…Another approach to mitigate the adverse effects of high gains on noise amplification is to adopt a cascade structure within the ESO [31]. Additionally, reduced-order ESO designs have been proposed to avoid noise amplification associated with high gains [45]. Departing from conventional strategies of nonlinear gain adaptation or reduced-order ESOs to address the impact of measurement noise, this paper introduces a novel approach: utilizing Kalman filter techniques to design ESO gains, resulting in the Kalman extended state observer (KESO).…”