Structural Design And Simulation Research Of Automatic Loading/Unloading Robot Based On Continuous Stamping

It is the rapid development of China's manufacturing industry,which has promoted the transformation of traditional stamping technology and the formation of advanced stamping technology.Due to large labor costs,low efficiency and poor safety,traditional stamping can no longer meet the producing needs.So robots and automation technologies have been introduced into stamping producing.Because of the features of scale,individualization and batch in stamping parts producing,robots will occur a serial of problems when it is operated on different production lines,such as the accuracy of loading/unloading and the changing trajectory.In the view of the above situations,this article will design a six-axis loading and unloading robot with specific configuration.Meanwhile,the corresponding kernel technologies of structural design,kinematics,trajectory planning,dynamics and so on are studied in-depth in this article,and trajectory control can be achieved by modular.The main research contents include:(1)By analyzing the disadvantages of traditional stamping producing,the application requirements of existing automated stamping producing lines are proposed in terms of efficiency,flexibility and precision.Taking the processing of the sheet metal chassis as an example,a three-dimensional model of automated stamping producing line was constructed.(2)According to the positional relationship between the robot and the punch press,main technical parameters of the robot are determined,and the main transmission components are selected and calculated,therefore a loading and unloading robot is designed.Finite element analysis of the main transmission components is accomplished with ANSYS Workbench to optimize structural design based on stiffness requirements.(3)Based on D-H method,the bar coordinate system of the loading and unloading robot is constructed,and the forward and inverse solutions of the kinematics are theoretically calculated.The robot model is established with MATLAB robotic toolbox and the D-H parameters are verified,then the forward and inverse solutions of the kinematics procedure are saved in two computing modules.According to the result of forward solution,the working space of the robot is simulated,and the influence of the main parameters of the robot is analyzed.(4)The trajectory planning is completed in Cartesian coordinate space to obtain the discrete data of each joint angle.The fifth-degree polynomial interpolation method is used to fit the discrete points of each joint angle into the driving function,and the trajectory procedures for loading and unloading are saved separately.The forward and inverse kinematics module and trajectory module are adopted in the MATLAB/Simulink simulation system to conduct an experiment,and the effect of robot stability on loading and unloading tasks can be analyzed by the experimental results.With driving functions of every joint imported into ADAMS,the visual trajectory of the virtual robot prototype is simulated to validate the rationality of the trajectory.(5)Based on the Newton-Euler equation for basic dynamic analysis,with the dynamic computing platform built in SimMechanics module,curves of each joint's driving torque are obtained so as to check whether the main transmission components at the joint of the robot meet the requirements.The simulation control interface of the loading and unloading robot is designed in the MATLAB/GUI module to control and display the simulation results of kinematics,loading and unloading trajectory and dynamics.The research shows that the requirements of loading and unloading trajectory used for the automated stamping producing line are met through the modular processing of the trajectory control,which has the value of popularization and use in stamping producing.