Variable structure control of a capsule robot system

Capsule robots have attracted great attention from researchers due to their potential applications in medicine. In this paper, the capsule robot system is studied from the control point of view, i.e. an underactuated system which has two degrees of freedom but only one control actuator. An exponentially stable robust nonlinear control scheme based on Lyapunov stability theory is studied on the capsule robot system. The proposed scheme is robust to parameter uncertainty caused by the imprecise measurement in real experiment. Simulation results are presented to demonstrate the robustness of the proposed scheme.