Study Of Modeling And Vibration Suppression For The Reconfigurable Robot Handling Flexible Payload

In modern manufacturing industry,the robot is widely used,with the accelerating of the manufacturing automation process;robot must be endowed the more flexible ways of working and wider applications.The traditional robot configurations are fixed when it designed based the same or similar tasks,so it has the poor flexibility.The modular reconfigurable robots were introduced to deal with the disadvantage of the traditional robot.In the fields of automobile and aerospace,the tasks about handling,locating and assembling of some flexible payload are completed by robots.Because of the inertness and gravity of the flexibility payload itself,it will cause the vibration to the payload during the movement of the robot;it will lead to the lower accuracy of the task.The static errors caused by structural parameters of the robot and the dynamic errors caused by the inertness and gravity of the robot itself both affected the accuracy of the robot similarly.The static errors of the reconfigurable robot are involved in the geometric errors of the module when it is produced and assembled.Due to the joints and connecting links are not rigid bodies absolutely,the inertness and gravity of the robot will cause the flexible deformation to itself.In this the position error of end effector caused by the static and dynamic error is analyzed.In order to study the vibration of the reconfigurable robot which handling flexible payload,this paper established the dynamic equation of the robot by using Lagrange equation firstly,then the flexible deformation of the payload was analyzed based on the deformation of screw and FEM(finite element method);and the position and orientation of a point on the flexible payload can be obtained.Then the dynamic equation of the flexible payload is established by using Lagrange equation.At last,the dynamic equation of the overall system is established by the interaction between end effector and the payload.The flexible payload will be caused vibration during the movement.For this problem,this paper using the superposition of basic functions and Particle Swarm Optimization to restrain the vibration.The joint angular velocity is planned by the superposition of basic functions,and takes those parameters of superposition function as the optimization parameters.The vibration suppression can be transformed into the optimization to the parameters based the relations between the modal coordinates and joint motion,and the relations between modal coordinates and deformation of the screw,then using Particle Swarm Optimization to complete the process.