Fractional-order Virtual Model Control for Trotting Motion of Quadruped Robot

Virtual model control (VMC) is the most widely-used method for motion control of quadruped robot. VMC could decrease the abrupt ground reaction force and realize compliant interaction between foot and ground at the cost of control precision. To improve the robustness and precision of VMC, we integrate a fractional-order virtual damper with the classical VMC and propose a fractional-order VMC (FOVMC) for quadruped robot trotting motion. And we provide the implementation details about optimization-based FOVMC parameter tuning method and carry out the trotting experiments on the quadruped robot platform. The experiment results demonstrate that FOVMC could improve the precision of single-leg motion control and achieve a better whole-body trotting performance than classical VMC.