A Study On The Optimization Of The Inverse Solution Of Six-degree-of-freedom Serial Manipulator

The laser processing technology has been widely applied in many fields such as aerospace and automobile manufacturing, and it has been developing to the trend of NC and integration. The control system of laser processing system is used to ensure the accuracy of laser processing system. Six-degree-of-freedom serial manipulator is widely used in laser processing system as the control platform because of the repeatability and precision characteristics.In this paper, the main research contents of the manipulator inverse kinematics and optimization are as follows:In this paper, the inverse kinematics solution of manipulator is analyzed. Firstly, coordinate system of each link of the manipulator is established by the method of D-H, secondly, the forward kinematics equation is derived by using homogeneous transformation matrix equation, and finally, on the above bases, the inverse kinematics equation of manipulator is derived.To solve the problem called singular configuration in the process of inverse kinematics solution frequently, the Jacobian matrix is obtained by using the method of differential transform and the singularity analysis is accomplished on this base, thus three singular conditions are obtained. The method of using the “improved damped reciprocal” instead of the original inverse is established for making the manipulator pass through the singular region and suppress the mutation joint velocity. Simulation results show that this method can greatly meet the requirements of passing through the vegetation smoothly and also can improve the accuracy of processing. The advantages of this method are avoiding solving the minimum singular, simplifying the algorithm and getting high accuracy.There may be machining error caused by the practical work piece pose deviation from the ideal posture in the laser machining process, thus the correction of work piece pose is of important significance in practical machining. In this paper, the transformation relations between work piece coordination and the coordinate system of the manipulator is obtained by using the coordinate difference between the practical coordinate values and the ideal coordinate values, which is called the method of 3 points. N umerical simulation results show that this method can make the machining position error no more than 0.0001 mm and the angle error no more than 0.0002°.This method reduces the machining error successfully.