The Structure Strength Analysis Of Motorcycle Frame Based On Virtual Prototype Technology

With the rapid development of China’s economy, motorcycles have been verypopular around the country. Consumers also put new requirements to motorcycles’appearance and function. So it is very essential for the existence of an enterprise todiversify its product appearance, improve product function and decrease the period ofnew products development. With complicated carrying capability, frame is the skeletonof a motorcycle that plays a role in supporting motorcycle engine, fuel tanks and eachcover panels as well as in bearing the weight of motorcycle users and goods. Thetraditional design method of motorcycles cannot meet the market demand anymore, soadvanced modern design method must be applied to ensure more reasonable structuresof motorcycles, reduce the design period, improve the motorcycles’ quality and enhancethe market competitiveness of an enterprise.This thesis sets the motorcycle frame of certain type as research object, applyingvirtual sample technology to give a static and dynamic strength analysis of motorcycleframe. Based on the analysis results and combined with Structure Strength Theory,corresponding structure of motorcycle frame has been improved so as to meet therequired strength. The main content of the thesis are as follows:①The establishment of CAD model for motorcycle frame: according to the CADdrawings provided by enterprises, it is in UG that the three-dimensional model,comprising the major parts of motorcycle frame, has been set up and fit together. In theend, the motorcycle frame model has been shaped.②The establishment of motorcycle frame’s the finite element model: Firstly weput the CAD model into HyperMesh (Pre-processing and Post-processing of the FiniteElement Software) that is the mainstream of the current industry and provide the modela geometry cleanup and grid partition. Secondly, we will set up the motorcycle frame’sthe finite element model. Finally, we will employ the RADIOSS of HyperWorks tocompute the first six rank free mode of frame (not including the sixth rank rigid mode)and contrast with experimental mode of frame to verify the reliability of the finiteelement.③The static strength analysis of motorcycle frame under all kinds of workingcircumstances: in the rated load, we regard the total weight of the driver, the passenger,goods, motorcycle engine, the fuel tank (tank with oil) and other parts as corresponding equivalent to the particle on the motorcycle frame. Besides, the frame structure strengthwill be analyzed under the condition of standstill and emergency braking.④The dynamic strength analysis of motorcycle frame under the circumstance ofbump barricade condition: we will set up rigid–flex multi-body-dynamics model ofmotorcycles and have a dynamic analysis of motorcycles passing through the bumpbarricade. At last, we will examine the stress and strain of flexible body frame and rearfork as well as check the dynamic strength based on the first strength theory.⑤The improvement of motorcycle frame: according to the static and dynamicstrength analysis, we aim to find out the weak points of frame strength and have acorresponding structure improvement. In the end, we will give a strength analysis to theimproved frame and check its structure again with the application of the first strengththeory.