Mechanical Engineering Science

Robust Sliding Mode Control for a 2-DOF Lower Limb Exoskeleton Base on Linear Extended State Observer

CHENZhenlei, GUOQing, YANYao, JIANGDan

Abstract


For the 2- Degree of Freedom (DOF) lower limb exoskeleton, to ensure the system robustness and dynamic performance, a linear-extended-state-observer-based (LESO) robust sliding mode control is proposed to not only reduce the influence of parametric uncertainties, unmodeled dynamics, and external disturbance but also estimate the unmeasurable real-time joint angular velocity directly. Then, via Lyapunov technology, the stability of the corresponding LESO and controller is proven. The appropriate and reasonable simulation was carried out to verify the effectiveness of the proposed LESO and exoskeleton controller.


Keywords


lower limb exoskeleton; linear-extended-state-observer; robust sliding model control; uncertain nonlinearity

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References


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DOI: https://doi.org/10.33142/mes.v2i2.3160

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