Efficient and Smooth Enhanced Curve Path Following of Underactuated Snake Robots

This paper investigates a curve path following problem for a class of planar underactuated bio-inspired snake robots. Based on an improved time-varying line-of-sight (LOS) guidance law and parametric cubic spline interpolation (PCSI) path-planning method, we propose a more advanced algorithm that is able to make snake robots follow an arbitrarily generated curve path on the ground. The improved LOS helps the snake robot to steer aggressively at a sharp turning point. Furthermore, to avoid the side-slip caused by the ground friction change, an integral controller is introduced in the design of the heading reference. Simulation and experiments on an 8-link custom-built snake robot are extensively conducted, and the results demonstrate and validate the effectiveness of the proposed algorithm.