Terminal Trajectory Planning Of Six Axis Series Industrial Robot

When the industrial robot performs the tasks of handling,welding and painting,it has strict requirements for the position trajectory,attitude trajectory and speed curve of the end of the industrial robot.However,the common position trajectory planning algorithm and attitude trajectory planning algorithm have the problem of trajectory mutation,and the speed planning algorithm has the problem of speed step,which will reduce the operation efficiency of industrial robots.To solve the above problems,this paper studied the Terminal trajectory planning algorithm of six axis series industrial robot,and designed the position trajectory planning algorithm,attitude trajectory planning algorithm and speed planning algorithm of the end of six axis series industrial robot to improve the operation efficiency.The main research contents were as follows:(1)Aiming at the problem of trajectory mutation in common position trajectory planning algorithms,the cubic quasi uniform B-spline curve was used as the position trajectory transition section to replace the part of trajectory mutation to realize the smooth transition,and the position trajectory transition planning algorithm was designed.The conditions to realize G2 continuity at the starting and ending points of position transition were analyzed.Therefore,the calculation method of spline control points was optimized,and the difficulty of algorithm implementation was reduced.The length of the position trajectory transition section was obtained by the complex six point Gauss-Legendre integral method,and the interpolation calculation of the position trajectory transition section was carried out by using the Newton iterative method combined with the six point Gauss-Legendre integral method.(2)Aiming at the problem of trajectory mutation in common attitude trajectory planning algorithms,an attitude trajectory transition planning algorithm based on cubic quaternion quasi uniform B-spline curve was proposed.The conditions to realize G2 continuity at the start and end of attitude transition were analyzed,and a simple method to obtain the control points of quaternion spline curve was given,which reduced the difficulty of the implementation of the algorithm.The angular displacement length of the attitude trajectory transition section was calculated by the complex six point Gauss-Legendre integral method,and the interpolation calculation was carried out by using the Newton iterative method combined with the six point Gauss-Legendre integral method.(3)According to the synchronization requirement of the total running time of the position trajectory and attitude trajectory at the end of the six axis series industrial robot,an asymmetric S-curve acceleration and deceleration control algorithm based on a given time was designed,and the synchronous speed planning algorithm was improved.In order to overcome the speed and angular speed step problems existing in the synchronous speed planning algorithm,a synchronous forward-looking speed planning algorithm was designed.The speed of the position trajectory and attitude of the end of the six axis series industrial robot after the smooth transition was planned.The synchronization requirement of the total running time was met.And the continuous speed curve,angular speed curve,acceleration curve and angular acceleration curve were obtained.The kinematics model of six axis series industrial robot was built in MATLAB software,which was used as the simulation platform to simulate the terminal trajectory planning algorithm of six axis series industrial robot.The simulation results verified that the algorithm can obtain smooth and continuous position trajectory,attitude trajectory and joint trajectory,continuous speed curve,angular speed curve,acceleration curve,angular acceleration curve and joint speed curve.And the operation efficiency of the robot was improved.Then,the actual verification was carried out on the actual robot platform,and the actual verification results were analyzed to further verify the effectiveness of the algorithm.