Gait transition based on CPG modulation for quadruped locomotion

Quadruped robots are required to implement a fast transition between gaits in situations such as an abruptly increase in speed, an unexpected obstacle to stride over. Considering these situations, we propose a novel approach to achieve fast gait transition within a step cycle period of locomotion. This approach relies on the central pattern generators (CPGs) to produce rhythmic control signals, along with a CPG modulation to harmonize the limb phases. Therefore, smooth and fast gait transition can be obtained. We implement our approach on a simulated quadruped model. Simulation results demonstrate the adequacy of the approach to execute smooth and fast gait transition within a step cycle period. In addition, we analyze the ground reaction force (GRF), the pitch angle and the roll angle of the quadruped model to evaluate the proposed gait transition approach.