Abstract: Biological snakes in nature have a variety of periodic motion patterns such as serpentine motion, linear motion and lateral motion. Gaits diversity has greatly improved the adaptability of natural snakes to complex environment. Biologists has proved that such rhythmic movements of vertebrate animals are generated by CPG (the central neural pattern generator). Special mechanical structure of a snake robot with high degree offreedom and locomotion characteristics of different gaits was considered to bulid a suitale CPG network model. Hopf oscillators were chosen as neuron models of a central pattern generator owing to their stable features. A snake robot prototype consisting of nine links and eight joints was designed to achieve serpentine locomotion in horionzonal plane and sidewinding locomotion in three-dimensional space using a simulation tool of ADAMS. A switching method between the two locomotion gaits was discussed. Simulation results show that the proposed model is effecitive in locomotion control of snake robots.

Key words: snake robot, Hopf oscillator, serpentine locomotion, sidewinding locomotion