Effects Of Head And Tail Movements On Dynamic Walking Performances Of A Quadruped Robot

Quadruped robot is a hot topic for robot research institutions and scholars because of its movement stability and flexibility, and large weight-bearing potential. Currently, the performances of quadruped robot are improving from low speed and static movement to high speed and dynamic movement. Previous studies have been mainly focused on bionic design and motion control of legs that play the role of supporting and propulsion. To achieve balance under high dynamic movement, it requires complex dynamic computation and increases the burden for control system. Inspired by the scenes that dogs and horses swing their heads forth and back rhythmicity when galloping and cats swing their tails left and right when walking on a balance beam, a14degrees of freedom quadruped robot D-Cat with a head and a tail acting as regulating mechanisms was proposed. By controlling the swing of the head and tail, the regulation of the body’s balance of the robot was realized, and the dynamic movement performances of the quadruped robot were improved. The main work of this dissertation are as follows:A quadruped robot experimental platform was built which includes a14degrees of freedom quadruped robot D-Cat with a head and a tail, and a control system with real-time servo motion control functions.A CPG network model with15coupled hopf oscillators for the14degrees of freedom of the quadruped robot D-Cat was established. The rhythmic signals generated by the CPG network were used as control trajectory of the robot’s joints, and rhythmic motion control of both trot and bound gait was achieved.The influence between the movements of the head and tail and the body movement was studied based on dynamics analysis and bionics observation. Finally, the control strategies of the head and tail were presented.The comparative experiments were designed for studying how the head and tail movements could improve the performances of the quadruped robot in terms of running speed, posture balance of the body and foot force.Experimental results showed that the head and tail movements could improve foot dragging, stabilize moving direction and decrease foot force from the ground. Quadruped robot D-Cat translational steadily in both trot and bound gait with speeds of0.402m/s and0.60m/s respectively.The results showed that utilizing head and tail etc. as regulating mechanisms has a positive effect on improving dynamic movement performances for quadruped robots.