Trajectory Planning Research Based On Cam Design Theory For Multi-joint Manipulator

With industrial robots are playing an increasingly important role in modern society,the multi-joint manipulator has an irreplaceable role in many fields because of its flexibility,which makes people have more stringent requirements on its performance.Under the condition that the terminal trajectory of the manipulator is known,and the working time has been determined,in order to make the manipulator accurately complete the work task,the force of the actuator and the mechanical structure arm is reduced,to generate a smooth and coordinated movement.Therefore,the joint acceleration of the manipulator is researched and analyzed,and a trajectory planning method of the multi-joint manipulator based on the CAM design theory is proposed,so that it can complete the work with better performance than the original trajectory planning method.The paper introduces the development status of robot technology at home and abroad as well as the research results of trajectory planning of multi-joint manipulator,and then discusses the characteristic index analysis of trajectory planning of manipulator and interpolation method of trajectory planning in joint space,and then analyzes the problems caused by the excessive maximum acceleration of manipulator joints.Combined with the analysis of the joint acceleration of the manipulator and the synthesis of the advantages of each trajectory function,a combined function trajectory curve method is proposed.This paper expounds the theory of CAM design,deeply studies the motion function programming of CAM theory,and makes a comparative analysis of CAM motion constraint and manipulator motion constraint.The modified trapezoidal acceleration trajectory function based on CAM design theory is proposed under the condition of satisfying the constraint condition of manipulator trajectory planning and fixed working time.The CAM motion trajectory function and the manipulator motion constraint condition are combined to solve the proposed function,and the modified trapezoidal acceleration trajectory function equation is solved.3R manipulator as the carrier,by study of the trajectory function for application analysis.Firstly,the D-H method is used to establish the mathematical model of the 3R manipulator,and then the kinematic analysis of the manipulator is carried out to obtain the kinematic equation,and the relationship between the joint variables and the end-effector posture is obtained.Then,the workspace simulation of the manipulator is analyzed.Finally,according to the requirements of the actual working space,the new method is applied to the trajectory planning of the manipulator,and the original manipulator trajectory planning is analyzed with examples.Finally,a 3R manipulator simulation model is established with MATLAB Robotics toolbox,and the trajectory function of the manipulator is simulated by MATLAB software.By comparing the maximum acceleration of each joint of the manipulator with two trajectory planning methods,the results show that the maximum acceleration of each joint drops by 15.33%.Trajectory planning method based on the theory of CAM design can not only ensure smooth trajectory curve,and decreased the joint maximum acceleration,to produce smooth coordination of movement.In this study,the actual work condition and the CAM design theory were established together,this paper put forward a more effective solution to improve the trajectory performance of the manipulator,which opens up new ideas and directions for further study on the trajectory planning of the manipulator.