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arXiv · 2302.11311

Model Based Position Control of Soft Hydraulic Actuators

Mark Runciman·Enrico Franco·James Avery·Ferdinando Rodriguez y Baena·George Mylonas
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Abstract

In this article, we investigate the model based position control of soft hydraulic actuators arranged in an antagonistic pair. A dynamical model of the system is constructed by employing the port-Hamiltonian formulation. A control algorithm is designed with an energy shaping approach which accounts for the pressure dynamics of the fluid. A nonlinear observer is included to compensate the effect of unknown external forces. Simulations demonstrate the effectiveness of the proposed approach, and experiments achieve positioning accuracy of 0.043 mm with a standard deviation of 0.033 mm in the presence of constant external forces up to 1 N.

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Mark Runciman, Enrico Franco, James Avery, Ferdinando Rodriguez y Baena, George Mylonas. 2023-03-03. Model Based Position Control of Soft Hydraulic Actuators. https://arxiv.org/abs/2302.11311

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