CPG-based straight path control of a snake-like robot for moving in various space width

Maintaining a straight path for locomotion of a snake-like robot can be easily controlled using any control architecture such as sine-based, model-based or others. However, a problem occurs when one or more of the control parameters are modified online, where the trajectory of the snake-like robot will deviate from its original path. In this paper, a biomimetic approach based on central pattern generator (CPG) is utilized to control the straight path motion of a snake-like robot. The CPG model is based on the phase oscillator, in which only one control parameter is used to control the locomotion. The novelty of the approach is the online body shape transition of the snake-like robot which is useful in adapting to various space width especially for rescuing and searching tasks. The major parts of this paper include: 1) a brief introduction of the phase oscillator model and the proposed CPG network, 2) a proposed activation function to control the body shape transition of the snake-like robot, and 3) a straight path control strategy. Simulation results confirm the effectiveness of the proposed straight path motion control method.