L1 adaptive control for bipedal robots with control Lyapunov function based quadratic programs

This paper presents an approach to apply L1 adaptive control for output regulation in the presence of nonlinear uncertainty in underactuated hybrid systems with application to bipedal walking. The reference model is generated by control Lyapunov function based quadratic program (CLFQP) controller and is nonlinear. We evaluate our proposed control design on a model of RABBIT, a five-link planar bipedal robot. The result is the exponential stability of the robot with an unchanged rate of convergence under different levels of model uncertainty.

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