Kinematic Analysis And Calibration Method Of 6-DOF Serial Robot With Non Pieper Configuration

Reconfigurable and flexible have become the development direction of the current industrial robot.The traditional Pieper criteria of the industrial robot is constrained by the criteria,it is difficult to meet the needs of configuration diversification.So the robot with non Pieper criteria has become a hot spot in the current research.In this paper,the kinematics model is studied.On the basis of solving the inverse kinematic model,the terminal trajectory is planned.Kinematic calibrating is carried out by using laser tracker.It lays a scientific foundation for the realization of the diversification of the 6R robot configuration.The main research contents are as follows:(1)Take the 6R robot developed with non Pieper criteria in the laboratory as carrier.The overall design scheme of the control system of chardware and software is introduced.Based on the D-H method,the robot's each link coordinate system is established.The forward kinematics model of the robot is derived.By using differential transform method to construct the Jacobian matrix,the singularity of the robot is solved.(2)The inverse kinematics model of 6R robot with non Pieper criteria is studied.The 14 linear independent inverse kinematics equations based on vector multiplication is utilized.With the elimination law and the method of characteristic value decomposition are combined,the unknown parameters are eliminated by using known connecting rod parameters.Then the symbolic matrix is transformed into a numerical matrix.Finally the robot inverse kinematics solution is got.(3)The robot manupulate trajectory planning is carried out in Cartesian space and joint space,and Utilizing four elements,three spline interpolation method,mooth trajectory motion of robot manupulate are completed.Based on the Robotics toolbox,the joint space trajectory simulation is carried out to determine the circular arc planning curve of any three points in the task space.And with the prototype of the trajectory planning algorithm to verify,robot trajectory planning accuracy is tested.(4)The error model of the robot is deduced by using differential transformation method.With the help of FARO laser tracker,parameters of each connecting rod by circumference method is measured.The kinematic calibration is completed by using geometric identification and parameter identification method to determine the parameters error of the robot link parameters,calculating the compensation value of each connecting rod by the method of least square estimation and improving the kinematic model.The kinematic analysis of 6R robot with non Pieper is studied in the article,and the end of its trajectory planning accuracy meet the requirements of the motion control of palletizing and carrying,so it has certain engineering application value.