Research On Kinematics And Robust Tracking Control Of Multi DOF Manipulatorrobust

With the development and breakthrough of basic subject theory and the progress of application technology,the related theory and technology of robot have been developed rapidly.With the application of robot in many fields,higher requirements are put forward for its structure,control accuracy and working efficiency.In this paper,the kinematics,dynamics and trajectory tracking control of a 6-DOF manipulator are studied.Firstly,the D-H method and the screw theory are used to derive the forward kinematics equation of the manipulator and the corresponding Jacobian matrix,and the correctness is verified by numerical calculation and simulation.On this basis,the singular configuration of the manipulator is found,and the correlation function between the torque of the end effector and the torque of each joint is determined;the operability of the manipulator is studied and analyzed,and the corresponding evaluation index is given.In order to solve inverse kinematics,a new algorithm is proposed,which is to use geometric method to find closed solution,then substitute the closed solution as the initial value of iteration into Newton Raphson method,and find the relatively accurate analytical solution,and verify the effectiveness of the new algorithm by numerical simulation.Secondly,the motion planning problem is divided into two sub problems: path planning and trajectory planning.Aiming at the path planning problem,this paper studies them in Cartesian space and joint space respectively,analyzes the advantages and disadvantages of the two path planning methods,puts forward corresponding planning strategies,and verifies them by numerical simulation.Aiming at the problem of trajectory planning,this paper first analyzes the point-to-point trajectory planning,puts forward several trajectory planning methods according to different design requirements,and then proposes the trajectory planning through the middle point on the basis of it,and verifies it by numerical simulation.Then,Lagrange method and Newton Euler method are used to establish the dynamic model of the manipulator.Considering the structure and practical significance of the 6-DOF manipulator,it is appropriately simplified,and the dynamic equation of the manipulator is established.The dynamic model is simulated by ADAMS software and programming,and the correctness of the dynamic equation is verified by comparing the results Then,the moment of inertia and gravity terms in the dynamic equation are simulated to analyze the influence of joint angle changes on them.Finally,uncertainties such as model error,friction term and external environment will cause disturbance to the control system,which makes the actual trajectory deviate from the trajectory obtained according to the theoretical model,resulting in the decline of trajectory tracking accuracy.Considering the influence of model uncertainty on trajectory tracking control,the neural network adaptive method and the control strategy of HJI theory are used to complete the corresponding robust control.Through the simulation analysis,it is verified that the designed robust controller can effectively weaken the disturbance of uncertainty to the control system,and achieve better trajectory tracking effect.