Research On Trajectory Planning Method Of Six-axis Manipulator Based On Time Optimality

In the modern manufacturing industry,intelligence is developing rapidly,more and more enterprises use industrial robots to replace human labor,in the dangerous working environment to ensure personal safety,while reducing the cost and greatly improve the production efficiency of enterprises.With the development of automation and computer and other disciplines,industrial robots are gradually improved in all aspects,making the current application more extensive.Nowadays,industrial robots occupy an important position.If our country wants to realize the transformation from industrial "manufacturing" to industrial "intelligent manufacturing",it is inseparable from the research and innovation of various technologies of industrial robots.As an important research topic in the field of robotics,trajectory planning is still a challenging problem that needs further research.In this paper,the trajectory planning method of six-axis manipulator based on time optimality is further studied.The specific work is as follows:(1)this paper introduces the background and research significance of manipulator trajectory planning,trajectory planning method at home and abroad and the research status,and the kinematics analysis was carried out on the robotic arm from the aspects of theory and use the MATLAB software is inverse kinematics simulation and analysis of the working space,to build six axis mechanical arm based on time optimal trajectory planning method research foundation.(2)analyze the cartesian space and under the joint space trajectory planning,the advantages and disadvantages of the final selection for trajectory planning in joint space,analysis of traditional trajectory planning method of polynomial,in view of the traditional 3-ph sigmoid jerk curve of trajectory planning method is put forward to improve after a period of 15-ph sigmoid jerk curve generated a smooth trajectory method.(3)The time optimization of the proposed method is analyzed,and the M coefficient is proposed to optimize the jerk curve,and the critical situation of each constraint condition is expounded.Finally,the running time of each joint is calculated,and the running time of each joint is synchronized to prevent unnecessary pressure on the actuator.(4)The feasibility of the method is verified by experiments.The experimental results show that the method can generate faster trajectories under the constraint conditions of each joint,and ensure the operation of the manipulator in the effective range.It also has better performance in efficiency and jerk inhibition.Compared with other methods,the experimental results show that the efficiency of the improved method is significantly improved compared with the existing methods,and the adverse effects caused by the degradation phenomenon can be minimized in the degradation mode.In the calculation time,the proposed method is obviously less than the previous methods.In addition to improving efficiency,another advantage of the15-ph sigmoid jerk curve trajectory is the suppression of the jerk value,which is of great significance for the precise operation of the robot.Comparing the spectrum of different methods,the experimental results show that the proposed method is more suitable for the application of robotic arm.Through the measurement position of the built-in encoder and the corresponding tracking error,it can be seen that the actual measurement curve is quite close to the reference curve with good consistency.The torque distribution changes smoothly throughout the motion without any saturation.The robot arm can track the trajectory accurately with ease.The experimental results on a robot arm are satisfactory,and the practicability of the method is verified.