Bionic Structural Design And Bounding Motion Simulation Of Quadruped Robot With A Spinal Joint

Quadruped robot research is a hot area in robotics. With the higher demanding of movement efficiency in the execution of their job functions, whether the quadruped robot can achieve high speed has been an important index to measure the movement performance of the robot. In order to solving the problem of robot with rigid body can hardly increase higher speed with the morphological change of body during moving,the dissertation proposes a new bionic structure that a quadruped robot with a spinal driving joint on body. The robot kinematics is analyzed, simplified model has been proposed and dynamic analysis of the simplified model is completed. The assessment of movement performance of the robot with a spinal driving joint is conducted by ADAMS experimental platform. The main research content of the dissertation is:Firstly, the present situation of quadruped robot is summarized and the movement limitation of the robot with rigid body is proposed. Based on the observation of the cheetah and other animals, the dissertation presents a model of a quadruped robot with a spinal driving joint, the bionic structure of the robot is designed, including the DOF Calculating, the determination of the size parameters,the choice of drive mode,The bionic structural design of the leg and the spinal joint, and finally completed the fabrication of the prototype.Secondly,the robot kinematics is analyzed. Using the D-H theory,the coordinate system of each leg’s DOF is established,the direct and inverse kinematics problems are solved by the generalized coordinate transformation and Euler transformation. The reachable workspace of the end of each foot is solved by the SimMechanics mechanical simulation module.Thirdly, according to the SLIP theory and Raibert’s virtual theory, the bionic structural model is simplified to be a planar model with two spring legs, and use the simplified model as the dynamic analysis model,use the bounding gait as the robot’s cyclic gait,then doing the dynamic analysis of the robot, and trigger conditions of each phase in bounding gait are judged.Finally, the dissertation applies ADAMS simulation software in the virtual simulation of the quadruped robot, and the simulation results of the quadruped robot with rigid body and quadruped robot with a spinal joint are compared, then analyzes the improvement on quadruped robot’s movement performance of the spinal driving joint. The related solutions are proposed according to the problems in the simulation, which establishes the foundation for the later prototype experiment.