Mechanism Design And Anlysis Of Heavy-Duty Blank Transfer Robot

In recent years,with the development of China's railways,urban subways and large construction machinery,the demand for large shaft parts has grown rapidly.At present,there are problems of high labor intensity and low degree of automation in the transfer of large shaft blanks.It is of great significance to use heavy-duty robots to transfer shaft blanks to improve the production efficiency of shaft parts and reduce the use of manpower.The purpose of this paper is to design a heavy-duty blank transfer robot that can complete the transfer of shaft blanks from the heating furnace to the forging press on the premise of meeting the requirements of high rigidity,high strength,and easy control,and carry on the structural size design and dynamic characteristic analysis to it.Firstly,a four parallel four-bar transfer robot of four-DOF based on technical parameters and task requirements was designed.The D-H parameter method,inverse transformation method and geometric analysis method were used to solve the forward and inverse kinematic problems;The total differential equation method and the vector product method were used to solve the robot's Jacobian matrix.And then,the length of the main link of robot is used as the design variable,combined with the specific constraints,and the global speed performance index is used as the target function,and the length of the link is optimized with the help of the MATLAB optimization toolbox;Solve the working space of the robot's end operator in the global coordinate system through MATLAB programming to verify whether the working space of the robot meets the task space of the subject.With the lightest weight of the link as the objective function,the strength conditions of the link,the pressure bar stability conditions and the amount of deformation as constraints,the width and thickness of each link are optimized with the help of ANSYS Workbench,and finally,based on the optimized link size,the robot structure is specifically designed,and the strength and end deformation of the robot are verified using the static analysis module of Workbench.It has been verified whether the designed robot meets the stiffness and strength conditions.Finally,the trajectory planning of each active joint of the robot is performed in the trajectory space,in order to obtain the joint angle trajectory with smooth motion trajectory and no sudden changes in speed and acceleration;The flexible parts discretized in ANSYS are imported into ADAMS to replace the original rigid body members,and the dynamic characteristics of the robot are simulated and analyzed.The motion stability of the robot under the rigid-flexible coupling model is studied.