Tracking Control of Snake Robots with Butterfly Spiral Propulsion for Multiscenario Applications

This work presents a butterfly spiral propulsion mode of snake robots to realize the tracking control on the objective trajectory in multiple scenarios. This method investigates the force mechanism of each body element in the yaw and pitch directions. The butterfly spiral gait mechanic and friction models are constructed to offset the lateral torque force caused by joint rotation. In addition, this work combines an integral part of improving the line of sight guidance scheme, which eliminates the robot's sideslip when tracking the curve track and enhances the body's adaptability to different scenarios. Lyapunov's theory proves the stability of the designed guidance strategy. Simulation and experimental results illustrate that the designed butterfly spiral gait and guidance scheme can provide the snake robot faster tracking results and more stable error performance than the cylindrical and conical spiral gait.