Research On Trajectory Planning And Control Simulation Of Quadruped Robot

Based on the body posture change of quadruped robot,the key problem of quadruped robot research is to improve the motion stability and environmental adaptability of quadruped robot by controlling the active joints of legs.In this thesis,the trajectory planning of quadruped robot and the control strategy to improve the stability of gait are studied.The main research contents of this thesis are as follows:In order to realize the stable motion of quadruped robot,the basic structure of quadruped robot is analyzed and the gait trajectory is planned.Firstly,the kinematics model of quadruped robot is established by D-H method;The inverse kinematics solution of quadruped robot is calculated by geometric method.Then,by analyzing the dynamics of quadruped robot,the mechanical stability of quadruped robot is studied,and the inverse dynamics of joint space is solved by PD control method.And,based on the spring loaded inverted pendulum(slip)model,the trajectory planning of the supporting phase end of the quadruped robot is carried out;Based on the compound cycloid,the trajectory planning of quadruped robot’s swing phase end is carried out.Thus,the diagonal gait movement of quadruped robot is realized,which provides a theoretical basis for the next research on gait stability control algorithm.Aiming at the problem that the body posture of quadruped robot is disturbed by the imbalance of support force in the process of diagonal gait movement,so as to affect the motion stability,the optimization control is carried out from two aspects to improve the stability of diagonal gait.The first is to control the initial position of the swinging leg end of the diagonal gait.The second is to compensate and control the landing point of the swinging leg end according to the body attitude feedback by detecting the change of the body posture of the quadruped robot in real time.Thus,the adjustment and control of body posture is realized,so that the body tends to the desired balance state when the robot moves.By building a quadruped robot simulation system on the MATLAB Simulink simulation platform,the above control strategy and algorithm to improve the motion stability of quadruped robot are verified and analyzed,which proves the rationality and effectiveness of the control strategy studied in this thesis.The experiment is carried out on the physical data of the prototype.Finally,the main research work and proposed methods are summarized,and the shortcomings are analyzed.Then,it puts forward the problems to be solved in the next research,as well as the research direction and ideas.