Rigid-Flexible Coupled Simulation And Optimization Of Backhoe Hydraulic Excavator’s Working Mechanism

As one of the main types of construction machinery, excavator is the main mechanical equipment which is used in earth-rock projects. There are all kinds of excavators, which are usually classified by their working member. As an important part of excavator, the working member is always in the very bad working condition. So the rationality and reliability of its structural design have received considerable attentions, which results in the necessity of carrying out further research.The traditional design method of excavator has been adopted in China for a long time. A series of feasible scheme can be listed on the basis of previous empirical formula. Then the ideal design can be selected to guide the design and production. However, this traditional method has many disadvantages, such as heavy workload, long design cycle, high costs. To meet the requirement of modern market, shorten the product cycle, reduce the costs and design the better product, it is necessary to use the modern design method in designing and researching excavator. The virtual prototype technology is the practical and feasible option which can meet the mentioned requirements above very well.The research object of this paper is the backhoe hydraulic excavator whose three-dimensional geometric model is set up. Then the kinematics and dynamic simulation and structure optimization are carried out. The main research contents are as follows.(1) Firstly, the basic composition, working principle of hydraulic excavator and several important parameters during the digging process are researched. The digging resistance is calculated and analyzed. Various hydraulic excavator parts models are created with Pro/E and they are assembled into the whole machine model.(2) Secondly, the three-dimensional model of the excavator is imported into ADAMS. Besides, the model of boom and dipper stick which are created in Pro/E are respectively imported into the finite element analysis software ANSYS. Then they are divided in mesh and the nodes are rigidified, through which the MNF neuter file of the boom and dipper stick can be exported(3) Thirdly, the boom and dipper stick model in ADAMS are replaced with the MNF neuter file to create the rigid-flexible coupling model and the kinematics and dynamics simulation proceed with the model.(4) Finally, with the ADAMS software the optimization design of the bucket-link mechanism is done.