Tracking Control Method of the Centre-of-Mass Velocity for aSnake-like Robot Based on the Continuum Model

The dynamics equations of the snake-like robot are reasonably simplified based on the continuum model. Based on the dynamics equations, the joint angle parameter set can be obtained to stabilize the centre-of-mass velocity in the case of no sideslip. Then, the parameter for stabilizing the centre-of-mass velocity with the limited normal friction is obtained by analyzing the relation between the probability of sideslip and the control parameter. On the basis of the stability of the centre-of-mass velocity, the parameter is acquired based on the continuum model to complete the velocity tracking when the robot doesn't sideslip. Finally, a controller is designed based on the above theoretical values. The above theoretical values are used as the initial values of the joint angle parameters, and the joint angle is adjusted by the speed feedback to eliminate the velocity error caused by the model approximation and the environment difference. The simulations are programmed based on Open Dynamics Engine. The simulation results show that the centre-of-mass velocity can track the expected speed, which verifies the validity of the proposed control method.