Co-simulation Of Wheel Loader Hydraulic System And Operation Mechnism

The loader industry in our country is still in the traditonal design and reserch mode that result in long perid and high cost for new project development. Nowadays, in the wake of mechanical electronic and hydtraulic technique intergration, the wheel loader is more complex than ever before and the traditonal mode is hard to fit the development trend. During the background this paper studied the co-simulation methord then built the mechnical and hydraulical intergration model that is helpful for evaluating and optimizing loader's comprehensive perfomance.1 After resrching on mechnical system modeling theory, built the 3D geometry model of wheel loader's operating mechanism with accurate dimensions, and then established the dynamic system by applying pysical joint restricts and prime motion for mechnism's character study.2 This paper studied complex hydraulic system modeling method by using EASY5 according to the basic equation of hydraulic mathematical model and the composition and function of the real system. The parameters of hydraulic model is determined by components'structure size, performance index and the hydraulic experimental platform's test results. Studying the dynamical characteristics of hydraulic system in a working period.3 Resrching on mechanical system and hydraulic system co-simulation methord. Refering to hydraulic cyliner's piston dyanmic equation and chamber pressure and flow equations, the parameters'interaction between different system is acquired for establishing input and output variables then realizing co-simultion. The accuracy of the combined modle is validated through the comparison the simulation results to the phsycal loader and experimental platform combination experiments'data, which is specially designed for flow and load controlling.4 Bucket resistance when spading is loaded based to the combined model for considering the influence of external load vary and mechinism motion to the hydraulic force during an working piriod.Because of considering the mechanical system inertia and hydraulic system dynamic characteristics, integrating the mechnical model and hydraulical model through parameter correlation makes the effective mass and external load vary with the moving of operating mechanism, which makes the co-simulation result in an working pirod more exactly than a single filed simulation. The intergrating model can partly replaced the physical prototype experiment, quickly get hydraulic system and mechnism's dynamic characteristics and provieds important reference for multiple optimization of loader. It could be applied to loader development process that will rich the characteristics of the loader evaluation mode, reduce development costs.