Vibration Characteristics Analysis And Optimization Of ATV Frame Using Modal Analysis Technology

All terrain vehicles are a new concept of the models. It’s often referred to ATV. The model different from cars, buses is that: use complex conditions; outstanding off-road performance; able to adapt to the sand, marsh, mud and other industries, can also b e used in military, fire, and other fields. According to the above features, the performance on the frame have higher requirements. Dynamic characteristics is one of the important performances. Frame is the skeleton of ATVs, have a greater influence on the vibration comfort. The thesis takes a company’s actual product(ATV frame) as example, the frame as study object, optimize the frame structure, improve the vibration characteristics so as to improve the comfort of the ATV based on dynamic performance analysis.The main text reads as follows:(1) According to the actual situation of the all-terrain vehicles frame, after appropriately simplified, use three-dimensional modeling software, build frame geometry.(2) After transform the geometric model into the IG S format. Import it into pro-processing Softwore, Hyper Mesh, then make the geometry cleanup, build the frame finite element model.(3) Based on the built finite element model, use the Radioss module in the FEM Softwore,Hyper Works, to performance the calculation modal analysis on the frame,gives the first eight natural frequencies and modal shapes of the frame structure, andanalyze the dynamic characteristics of the frame.(4)Use LMS modal testing system, performance experimental modal analysis on the frame, test the experimental output in the use of Modal Criteria and FRF France,and compare the experimental and the calculation output, verify the correctness of thefinite element model, And lay the foundation for the structure improving and size optimization below.(5) Analyse the effects from road and engine excitation on all-terrain vehicle vibration comfort, and determine what cause the frame resonance.(6) According to the results of modal analysis, combine modal characteristics, propose, two options to improve the frame structure.(7) In accordance with the actual situation of the structural optimization theoryand actual condition of the frame. Size optimization is used on the frame structure optimization. Through sensitivity analysis to identify the optional design variables, build the optimized verify the optimization results.