Simulation Analysis And Optimization Of Rigid-flexble Coupling For The Loader Working Device

Loader often works in large-scale construction sites or open-pit mine,which made it prone to strength,stiffness and stability failure because of changing operating sites,complex environment,the structure of a variety of working conditions.The design of working is a direct impact on the work loader performance which is composed of boom,rocker,connecting rod and bucket.The dynamic model becomes more complex due to the coupling between rigid body motion and elastic deformation,which brings great difficulties to the practical problem.In fact,the complex dynamics between the large-scale motion of the flexible body and its own deformation has been recognized as a difficult problem.This research has become one of the hotspots in this field.Based on the multi-body dynamics and finite element theory,the kinematics and dynamics simulation of the loader are analyzed with Solidworks and ADAMS,and the mechanics analysis and modal analysis of the working equipment are carried out based on the dynamic and static method and finite element method.The optimization of the parameters of the boom is done,which provides a reference for the theoretical research and development of the loader working device.Firstly,the loader machine model is built by solidworks,according to the fine ratio to determine the standard,the key components on the working device are defined under four operating conditions,which defined as rigid body components directly into ADAMS,the model of the flexible body is flexibly processed in ANSYS,and then the modal data file obtained after the modal analysis is imported into ADAMS.Constraints is added to the model In ADAMS,the rigid-flexible coupling model was established under the backgrounds of the edit driver and load function were added to the four operating modes respectively.Then the kinematics and dynamics of the rigid-flexible coupling model are simulated and analyzed.The velocity and the stress history curve of the main hinge of the boom are obtained,the dangerous working position obtained and the inertia force is calculated according to the acceleration curve under different working conditions,then based on the dynamic and static method the position of maximum deformation and the maximum stress were found by the mechanical analysis of the boom.The elastic modulus of the oil was calculated,and the first six modes of the device were analyzed according to the results of the elastic restraint analysis.The factors influencing the natural frequency were found and the resonance frequency was determined with the engine excitation frequency.Finally,the parameters of the boom were optimized according to the above analysis results,and the optimization results were analyzed and verified.the stress distribution of the boom is more closer to the isostatic distribution and the structure is more compact and light after optimization,which indicated the design is more excellent.In this thesis,the rigid-flexible coupling model is obtained based on the method of multi-body dynamics and finite element method.The slenderness ratio is taken as the basis of flexible body.The finite element analysis of the boom in the working device is carried out based on the simulation results obtained from kinematics and dynamics,.The results provide reference for the optimization design of the boom parameters.The research ideas and methods of this paper can provide references for the virtual simulation of engineering machinery and the optimization of structural parameters.