Research On Forward-looking Interpolation Algorithm Based On Trajectory Smooth Transition Of Manipulator

At present,industrial robots have been widely used in transportation,welding,spraying and other scenes.With the continuous development of industrial intelligence,high-speed and high-precision work content puts forward higher requirements for the execution efficiency and movement stability of the robot.In order to give consideration to the efficiency and stability of robot motion control as much as possible,based on the trajectory planning of robot arm,this paper studies the algorithm of continuous trajectory smooth transition and motion control of robot arm,and proposes an improved forward-looking interpolation algorithm based on continuous trajectory cardinal spline transition.The main research contents are as follows:In order to minimize the collision free trajectory of the robot in the workspace,this paper studies the Dijkstra algorithm and A*algorithm in the trajectory obstacle avoidance algorithm.Based on the grid method,the two algorithms are simulated and compared in MATLAB,and the advantages of A*algorithm in the small range of trajectory search are highlighted in a visual way;through the establishment of arc transition model and cardinal curve transition model,the continuous zigzag trajectory obtained by obstacle avoidance algorithm is smoothed to reduce the jitter when the robot is running,and the characteristics of cardinal spline curve are emphatically analyzed based on the simulation results,highlighting the flexibility and efficiency of cardinal spline smooth transition algorithm in trajectory planning.In order to prevent the trajectory shape from changing due to speed,the limitation of the speed between continuous tracks is consideredIn order to take into account the efficiency and stability of interpolation control,this paper proposes a new flexible acceleration and deceleration control algorithm,which improves the cosine acceleration and deceleration algorithm by using the characteristics that cosine acceleration and deceleration algorithm and straight-line acceleration and deceleration algorithm have the same calculation results in trajectory planning,and uses Lyapunov stability theorem to prove the reliability of the algorithm.And the simulation results show that the new flexible acceleration and deceleration algorithm has the advantages of flexible control and short time consumption in MATLAB.Based on the new flexible acceleration and deceleration control algorithm,the forward-looking interpolation algorithm is optimized;considering the diversity of the continuous trajectory interpolation,the cardinal spline interpolation algorithm is also designed by using the Taylor expansion method.The visual interface in MATLAB is used to verify the spatial trajectory of the algorithm.Firstly,the kinematics of six axis manipulator is analyzed,and the D-H model is established by robotics toolbox,and the optimized forward interpolation algorithm is simulated based on the model.Secondly,several algorithms are used to simulate the optimal collision free trajectory,and the results show that the forward-looking algorithm based on arc ransition and the forward-looking algorithm based on cardinal curve transition are 26.32%and 27.52%more efficient than the traditional algorithm,and the efficiency of interpolation based on cardinal curve transition is 1.62%more efficient than that based on arc transition.Finally,the control system is built based on ER30 manipulator platform,and the interface and program for motion control are designed,and the stability and efficiency of the improved speed planning algorithm are verified by direct transition,arc transition and spline transition respectively.The results show that the manipulator can run efficiently and stably.