Dynamic Modeling Analysis And Structure Optimization Of Industrial Robot With Consideration Of Multiple Closed Chains

In the research and development of the design of palletizing robot body, dynamics analysis not only relates to selection of driving motor, but also plays an important role in guiding for lightweight design, trajectory planning and other aspects. So establishing an accurate dynamics model of palletizing robot for analysis is of great significance. The driving torque characteristics of the palletizing robot which contains multiple local closed chains can not be reflected well in simplified dynamic model of the single closed chain because of its lower calculation precision.In this paper, a kinematics mathematical model was established and the related analysis was done. Considering the interaction of multiple local closed chains, a rigid body dynamic model was established. After verifying the accuracy of the model, a dynamic optimization target was proposed to optimize structure parameters of the palletizing robot.Firstly, a palletizing robot kinematics model was established based on D-H method, and the expressions of positive and inverse solutions of robot’s joints were obtained. A quantification assessment method of the reasonableness of the workspace was proposed through analyzing the characteristics of the workspace. Based on the analysis of structural characteristics which contains multiple local closed chains, the palletizing robot’s dynamic equations were establish by using Kane method and the expressions of positive joint torque were deduced. Then, a virtual prototype model of palletizing robot was established for kinematics and dynamics simulation analysis in ADAMS. By comparing the results of simulation analysis with mathematical model calculation, the accuracy of the mathematical model was verified. Based on the model, dynamic multi-objective optimization evaluation index was put forward, and the bar parameters of palletizing robot were optimized. Meanwhile, by taking the influence of spring balance structure on the palletizing robot dynamic characteristics into consideration, the dynamic optimization for structural parameters of spring balance was carried out. Finally, a group of parameter values were get to optimize the dynamic performance of the palletizing robot.