Frame Structure Analysis And Related Issues Research For A Sweeper Vehicle

Vehicle Frame as the important bearing part of an automobile, supports someaccessories such as engine, transmission system, steering system, suspension, drivingcab, container, and withstands all kinds of force．So the performance of frame structureaffects the whole vehicle performance． It can realize the static and dynamiccharacteristics of vehicle frame as early as possible, to provide guidance for vehicleframe optimization by using finite element methods. Topology optimization for framecan improve its mechanical property; reduce the use of material, save research anddevelopment costs.It has been found that the whole frame stiffness of a sweeper vehicle is small andthe deformation of middle frame is large in its modified design and prototypetrial-manufacture phase. In order to solve the problem of large bending deformation offrame to improve its mechanical property, this paper taking the vehicle frame for theresearch subjects, creates the finite element model with shell as basic unit in thesoftware of HYPERMESH, and analyzes static response of frame by use of generalFEM software of ANSYS. Deformation and stress distribution of frame in Typicalworking conditions are analyzed, and frame bending deformation of heavy hammer testare compared. Natural frequencies of the fame are obtained through modal analysis,and the weakness of the frame is found out by frame harmonic response dynamicanalysis using Ls-dyna software.In consideration of the existence of uncertainty in frame actual structure, theanalysis results of frame certain structure will deviate from reality. In order to simulatethe mechanical properties of the frame really and fully consider some of theuncertainty factors to the influence of static and dynamic response of frame, based onthe analysis of certain frame structure, the uncertain frame parameter model isestablished. Using interval analysis method to analyze the response range of framewith structure and material uncertainty parameters, and compare the results with thatof certainty analysis.Based on the former static and dynamic analysis results and interval analysis results,topological optimization is carried out. The volume fraction of the frame is taken asthe optimization objective function, and the bending deformation of frame asconstraint, the new local topological structure of frame is obtained. As result, it improves frame stiffness and bending deformation.