Research Of Time Optimal Trajectory Planning Algorithm On Industrial Robots Based On Dynamic Models

With the continuous improvement of automation control standards for industrial production lines,higher requirements have been placed on the trajectory planning ability of industrial robots.To improve their production efficiency,the most important aspect is the study of time optimal trajectory planning algorithms.The paper takes domestic six axis industrial robots as the research object,and aims to solve the problem of industrial robots stopping due to joint over-speed during interpolation motion when facing large poses,near singular movements,etc.,and to re plan a time optimal trajectory that meets the motion requirements.The specific research content is as follows:(1)According to the improved DH parameters,the kinematics model of the six axis industrial robot is established,and the forward kinematics analysis is carried out.Algebraic method is used to solve the inverse kinematics of the robot.Using Newton Euler iteration method and Lagrange equation method to model the dynamics of a six axis industrial robot,write its dynamics modeling program in MATLAB,and conduct data simulation tests to verify the correctness of the program.(2)A method using improved differential evolution(IDE)algorithm is proposed to optimize the excitation trajectory parameters in the dynamic parameter identification of six axis industrial robots.Firstly,a dynamic model of a six axis industrial robot is established using the Newton Euler iteration method,and the condition number of its minimum inertia parameter observation matrix is used as the optimization objective function;Secondly,by improving the differential evolution algorithm,a reverse optimal worst strategy is introduced to improve the initial value of the population,and an adaptive algorithm is used to improve the mutation factor and crossover factor;Finally,the improved differential evolution algorithm is used to optimize the design of Fourier series that meet the constraints of the robot as the excitation trajectory to complete the dynamic parameter identification of the robot.(3)In response to the problem of robots stopping due to joint over-speed during interpolation motion in the face of large postures,near singularity,and other movements,the S-type velocity planning algorithm is improved to obtain an S-type velocity planning algorithm with non zero initial and final acceleration.This enables the robot to re plan the over-speed zone of the joint and obtain the time optimal trajectory that meets the motion requirements.(4)By building an experimental platform for a six axis industrial robot,the dynamic parameters studied and the time optimal trajectory planning algorithm were tested and identified to verify the accuracy of the dynamic parameters and the feasibility of the time optimal trajectory algorithm.Run the improved S-type speed planning algorithm after simulation verification on the robot experimental platform to further verify the effectiveness of the algorithm.