Research On Improved Cubic Spline Robot Trajectory Planning Based On IPSO Algorithm

With the optimization and upgrade of the manufacturing industry,industrial robots have been deeply integrated with the core manufacturing processes,changing the traditional mode of work.Industrial robots play an increasingly important role in industrial production,offering significant advantages in reducing production costs and improving work efficiency.As a result,trajectory planning of robots has become a core research area.This paper selects the ABB IRB 120 robot as the research object,and conducts a detailed study on its forward and inverse kinematics,trajectory planning,and time optimization.The main contents are as follows:(1)The robot kinematics were analyzed and solved.The robot’s mathematical simulation model was established using the D-H method to establish the robot’s link coordinate system,and the forward kinematics and workspace were analyzed and solved.At the same time,the pose separation method was used to simplify the calculation,and the inverse kinematics problem of the robot’s end effector was converted to the wrist center,avoiding complex inverse calculations and improving the efficiency of the solution.(2)The trajectory planning method of the robot was studied.Linear and circular arc interpolation in Cartesian space and polynomial and cubic spline interpolation trajectory planning in joint space are investigated,respectively.The cubic spline interpolation function was improved by modifying the midpoint of the starting and ending time intervals,ensuring the continuity of speed and acceleration at each time node.By using the improved cubic spline interpolation,the acceleration of the robot at the start and end of the trajectory planning could be continuously varied from 0,while maintaining the continuity of velocity and acceleration at each time node.(3)The time-optimal trajectory planning of the robot was studied.Based on the standard particle swarm algorithm,a dynamic method was introduced to assign learning factors and the inertia weight was modified.The improved particle swarm optimization(IPSO)algorithm showed better convergence speed and convergence times.A method was proposed to establish the robot trajectory model using improved cubic spline curves and to perform time-optimal trajectory planning using the IPSO algorithm.The simulation analysis verifies the feasibility and effectiveness of the method designed in this paper for robot trajectory planning.The results show that the trajectory planning method shortens the robot’s motion time by 30%,greatly improves the work efficiency,effectively reduces the vibration caused by sudden changes in acceleration at the beginning and end of its work,and ensures the smoothness of work.