Nonlinear Control of a Hydraulic Exoskeleton 1-DOF Joint Based on a Hardware-In-The-Loop Simulation

Abstract

Aiming at the difficulty of debugging the exoskeleton control system driven by a hydraulic cylinder, a research method of a nonlinear control strategy for the hydraulic exoskeleton system with 1 degree of freedom (DOF) joint is proposed. Based on a hardware-in-the-loop (HIL) simulation, this method establishes the dynamic model of the 1-DOF joint system of the hydraulic driven exoskeleton, constructs the HIL simulation test platform based on the Linux real-time kernel patch, and studies the nonlinear control strategy of the 1-DOF joint system on this platform system. The control effects of the PID control algorithm and the backstepping method on nonlinear control are compared, and the controller parameters are tested on the HIL simulation platform. From the experimental results of the HIL simulation, the research method has the advantages of low cost, high efficiency of system development, safety, and reliability. It has important reference value for the development and debugging of a hydraulic exoskeleton control system.