Research On Path Planning Method Of Tea Picking Robotic Arm Based On Optimal Time Control

Taking Taiping Houkui tea in Anhui Huangshan as the research object,and planning the optimal picking path of the robotic arm to improve the tea picking efficiency of the robotic arm.Ant Colony Algorithm(ACA)and Polymorphic Ant Colony Algorithm(PACA)are analysis,and improve the polymorphic ant colony algorithm and apply it to the path planning of tea picking points in three-dimensional space;Analyze cubic polynomial interpolation and quintic polynomial interpolation,and combine the two to form a 3-5-3Partial path planning by piecewise polynomial interpolation.Analyze and improve the Firefly Algorithm(FA),and use the improved Firefly Algorithm to optimize the interpolation time.(1)Kinematics analysis and platform construction of the robotic arm.The DH(Denavit Harenberg)modeling method is used to establish the coordinate system of the connecting rod of the manipulator,and the forward kinematics and inverse kinematics analysis of the manipulator are carried out.Based on the Robot Operating System(ROS),the control platform of the GLUON robotic arm was built,and the Real Sense D455 depth camera was mounted on the robotic arm to perform hand-eye calibration,which laid the foundation for the robotic arm to pick tea.(2)Three-dimensional path planning of tea picking points,detailed analysis of the path planning of ACA and PACA,ACA convergence is slow and there will be detours.Although PACA can improve the search efficiency of the algorithm,it will be impossible to choose the next situation where the algorithm stalls at a picking point.The pheromone weighted value,the state transition probability weighted value and the maximum pheromone concentration were introduced to improve PACA,and the improved PACA was used to plan the threedimensional path of tea picking points.Compared with ACA and PACA,the path planned by the improved PACA is shortened by about 34% and 20% respectively,and the convergence speed is about 23% higher than that of ACA,slightly lower than that of PACA,but the algorithm is more stable.(3)Local path planning of the robotic arm.Using cubic polynomial and quintic polynomial interpolation to plan the path of the manipulator from one picking point to another picking point,the joint acceleration cannot be constrained,the calculation amount is large,and the Runge phenomenon occurs.Combining the cubic polynomial and the quintic polynomial into a 3-5-3 piecewise interpolation polynomial,the trajectory planned by the 3-5-3 interpolation polynomial is smooth and continuous,and can form constraints on the speed and acceleration of each joint at the same time,and the calculation amount is less than the fifth degree Polynomial interpolation,and no Runge phenomenon.The Firefly Algorithm(FA)is improved,and the improved FA is applied to the optimization of the interpolation time.The optimized interpolation time is shortened to about 20% of the original.And the convergence ability is improved by about 25%.The time-optimal tea picking path in this paper is mainly reflected in the shortest picking point path in three-dimensional space and the optimal local picking time.Combining the two can save a certain amount of time during the tea picking process,thereby improving the picking efficiency of the robotic arm.