Trot Gait Planning And Control Of Quadruped Robot On Non-flat Terrain

As a typical mobile robot,quadruped robot based on tetrapods has good flexibility and environment adaptability.It has great advantages and development potential in transportation,patrol,rescue and recreation.However,these advantages bring not only wide application prospects for quadruped robot,but also higher requirements for its motion control.With the development of quadruped robot technology,stably walking on flat ground can no longer meet the application requirements of robot in higher level,and its development trend is moving towards in more complex environment.But in fact,fast and stable motion of quadruped robot in non-flat terrain still faces a series of problems and challenges.In order to solve such problems,this thesis will carry out research from motion planning and motion control.Firstly,the mechanical structure of the quadruped robot was analyzed based on the research on the physiological structure and motion characteristics of the biological dog.On this basis,the single-leg kinematics model of the quadruped robot was established,the forward and inverse kinematics and Jacobian matrix were solved,and the single-leg foot reactable workspace was analyzed.Secondly,the planning of the trot gait is completed.According to the movement characteristics of the trot gait,the generation of the landing point,the trajectory planning of the swinging foot and the trajectory planning of the centroid position were completed.At the same time,aiming at the problems of the robot moving on the non-flat terrain,the control strategy of the robot moving on the non-flat terrain is proposed.Thirdly,the motion control of quadruped robot on non-flat terrain was studied.The design of support phase controller based on MPC and swing phase controller based on VMC are completed respectively.The state machine containing non-flat terrain motion control strategy is used to combine the two controllers and complete the motion controller design.At the same time,the whole robot simulation platform was built to complete the robot motion simulation research under the flat,slope and convex plate terrain.Finally,on the basis of the above theory and simulation analysis,to verify the feasibility and effectiveness of the motion planning and motion control theory of quadruped robot moving on non-flat terrains.a prototype experimental platform of quadruped robot was built to complete the experimental research in three different terrains: flat,slope and convex platform terrain.The research results of this thesis solve the problem of stable motion of quadruped robot with trot gait under non-flat terrain to some extent,and have a certain research significance to improve the robot’s motion performance and environmental adaptability.