Design And Research Of Large And Medium-sized Heavy-duty Bar Transport Manipulator

Gantry crane is the main method for some electrical equipment company to transport the large bar(5-13 meters,2-12 tons)to the machine for twining insulation materials.During winding process,dust and temperature in workshop greatly affect product quality,so enterprise upgrades workshop to closed constant temperature dust-free workshop,and raw feeding method is no longer applicable.According to the actual needs,a large and medium-sized heavy-duty rod transport arm is developed in this paper,and the overall mechanical scheme is designed.Then,multi-body system dynamics analysis and durability analysis are conducted by ADAMS.At last,parametric modeling and optimization,structural lightweight design and vibration analysis are made on its key parts to further improve the manipulator.The specific work is as follows:1)Overall design of heavy-load transport manipulator.To ensure safety,this paper takes the maximum bearing capacity of 16 tons as the design target.Firstly,the overall design scheme of heavy-duty transport manipulator with two-degree-of-freedom is determined,according to the workshop layout and production requirements.Secondly,comparing the advantages and disadvantages of different mechanical arm axial expansion drive schemes,finally choose the ball screw drive.Due to the large load,it requires high stability and safety.The stiffness check is carried out for the parts where the mechanical arm is under a large force,and the reinforcement is designed for the B-level mechanical arm to ensure the stiffness requirements;2)Modeling and simulating of heavy-duty manipulator based on ADAMS.According to the overall scheme,the dynamics simulation model of the manipulator is established.Its key parts are flexibly with ADAMS/Flex module to establish the rigid-flexible coupling model,the operation shows that the mechanical arm works reliably and with no flipping.Then the stress and deformation cloud pictures of key parts during movement are obtained in ADAMS/Durability module,and compare it with the above stiffness calculated results.The simulation results show that the designed heavy-duty manipulator can ensure the motion accuracy and meet the requirements of strength design;3)Analysis and optimization of heavy-duty mechanical arm based on ADAMS.The reinforcement bar of the B-class mechanical arm is optimized through the simulation iteration.When the plate thickness is 20 mm,right-angle triangles(400mm×60mm)of the same shape are cut off at each end of the reinforcement.In addition,eight rectangular holes(120mm×80mm)are dug on the bottom of the A-level mechanical arm for lightweight design.Finally,Adams/Vibration module is used to obtain the modal mode pattern diagram and corresponding frequency.In accordance with the lowest natural frequency,it can be concluded that the mechanical arm does not resonate with the motor.The design and research of heavy-duty transportation mechanical arm based on ADAMS can effectively improve its strength and stiffness,save materials and reduce inertia force.It provides certain reference for the design and manufacturing of physical prototype.