Optimized Design of Dynamic Stiffness of 6-DOF Tandem Robot Based on Response Surface Method

In order to improve the structural stiffness and vibration frequency of industrial robots, a robot structure optimization method based on multi-objective dimensional optimization method is proposed in this paper. The method firstly establishes the finite element model of the whole robot considering the torsional and overturning stiffness of each joint, corrects the joint stiffness to reduce the error through the modal test alignment method, and obtains the inherent frequency and modal vibration pattern of each order of the robot. Then, based on this model, the sensitivity analysis of the optimized variables is performed, and the stiffness of the rotating seat is the most influential factor on the stiffness of the robot. Finally, the target drive size optimization method is used to optimize the structure size of the turntable. The method was successfully applied to the analysis and optimization of a 220 kg multifunctional robot for handling and welding, and the results verified the usability and effectiveness of the analysis and optimization method.