Research On Kinematics And Motion Planning Of6R Robot Manipulator

In order to adapt to the modern manufacturing’s large-scale production and improvework efficiency, it requires that robot manipulator should have high-efficient inversekinematics algorithm and smooth and time-optimal trajectory. Therefore, this paperdiscussed and studied the solution to inverse kinematics and time-optimal trajectoryplanning problems. A new inverse kinematics algorithm based on the back propagationneural network and the radial basis function neural network, and a new time-optimaltrajectory planning algorithm based on genetic algorithm were proposed in this paper.Firstly, the theoretical knowledge of robotics was introduced. The representation ofrobot manipulator’s position and posture and homogeneous transformation matrix wereprovided. The D-H parameters and coordinate system of robot manipulator werediscussed. Forward and inverse kinematics were analysed and the correctness ofkinematics was verified by MATLAB simulation. This part provided theoretical basis ofsubsequent research.Secondly, the solution to inverse kinematics was studied. For the highly complexand nonlinear solution to inverse kinematics, a kind of mixed networks for inversekinematics solution were presented in this paper. The structure of mixed networks wasbased on one RBF (Radial Basis Function) neural networks and two BP (BackPropagation) neural networks. The number of RBF neural networks’ hidden nodes wasconfirmed automatically when trained. The BP neural networks used high-efficiencyLevenberg-Marquardt algorithm. The simulation compared several algorithms of BPnetworks. And it also showed that inverse kinematics problem could be solvedeffectively.Lastly, the trajectory planning problems were researched. The ploblems of trajectoryplanning in both Cartesian space and joints space were discussed. The principle, qualityand solving method of control points of the fourth order cubic B-spline curve werediscussed in this paper. This paper also discussed the principle of genetic algorithm thenproposed a new time-optimal trajectory planning algorithm based on genetic algorithm.This algorithm used fourth order cubic B-spline curve to plan trajectory of PUMA560manipulator’s first three joints, then used genetic algorithm to achieve time-optimaltrajectory planning. The simulation results showed that this method could solve theproblem of time-optimal trajectory planning of robot manipulator.