This paper,closely based on the application of MD-1200 palletizing robot in point-to-point mode,had presented the method to optimize the trajectory of palletizing robot based on energy optimization,including kinematic and dynamic modelings,trajectory planning and optimization.Then,the experiment on MD-1200 palletizing robot was achieved.The main contributions were concluded as following:In terms of kinematics,the structure of MD-1200 palletizing robot was analyzed.According to D-H method,the robot connecting rod coordinate system was established and its direct and inverse kinematics model was deduced.Based on the dimension parameters,the workspace and cross section shape were obtained in MATLABIn the aspect of dynamics,Kane function was used to derive the joint driving torque.And palletizing robot inverse dynamic model without friction torque was established.Based on stribeck friction model,the friction torque of each joint was got.On this basis,the MD-1200 palletizing robot complete dynamic model was achieved.In the trajectory planning,based on the kinematic model,the 3-4-5 polynomial motion law had achieved the mapping relation between operating space kinematic parameters(displacement,velocity,acceleration)and joint space kinematic parameters(angular displacement,angular velocity,angular acceleration)in operating space.And using quintic non-uniform B-splint motion law,the mapping relation between joint space kinematic parameters and operating space kinematic parameters had been achieved in joint space.According to the inverse dynamic model,torque of each joint was obtained.The dynamic performance,friction energy and average energy of joins in unit time of the palletizing robot under the two trajectory planning methods were evaluated.And the maximum acceleration of end-effecter and period of motion and their effects on the energy of joints was considered.The result of simulation shows that quintic non-uniform B-splinemotion law has more advantages in terms of trajectory planning.Based on the weighting factor method,a multi-objective evaluation index including energy and dynamic performance was proposed.The optimization solution was obtained by using the genetic algorithm combined with quintic non-uniform B-spline motion law to optimize the trajectory.By comparing the dynamic performance,friction energy and average energy of joins in unit time of the palletizing robot before and after optimization under the "door" trajectory,the result shows that the optimized trajectory has significant effect on improving the dynamic performance and energy consumption.In the experiment,the MD-1200 palletizing robot experiment platform was established to verify the researches on trajectory planning and trajectory optimization.The method,which was aimed at energy trajectory optimization,was proved to be effective in ensuring the palletizing robot dynamic performance and improving the energy of joints.The research of this paper is of important significance in enriching the research of palletizing robot trajectory optimization and achieving lower energy operation in engineering application. |