The Structural Analysis And The Dynamic Characteristic Research With Engine Vibration Of The Motorcycle Frame

Motorcycle chassis frame is one of the key parts of motorcycle. The structure of chassis frame directly influences the comfortableness and security of motorcycle.Basing on the measure data of a sample motorcycle chassis frame, establishing the frame mode of Pro/E, making the use of the finite element method and applied ANSYS to analyze it, the dissertation include static stress, deformation, analysis data, and display. Consequently, according to the analysis' result, searched of the key place of danger stress, presented matters need attention to preventing some problems of design and process procedure so that it can decrease the danger stress of key place.Road excitation and engine excitation are two origins causing the vibration of motorcycle chassis frame. This paper focuses on how to reduce the resonance resulted from the force frequency of engine in accord with the inherent frequency of the frame . The Finite Element Analyze (FEA) has been used to analyze the characteristic of the vibration of the frame. The dynamic characteristic has been deeply and systematically comprehended through the modal analysis and harmonic response Analysis. Modal analysis is a well-established technique, which provides the definition and paths of inherent dynamic properties (natural frequencies and mode shapes) of the structure that are related to the stiffness and mass properties of structure. Harmonic response analysis provides the ability to predict the sustained dynamic behavior of structures by sustained cyclic load, to verify whether the designs will successfully overcome resonance, fatigue, and other harmful effects of forced vibrations. It provides the important basis of solving the vibration of the motorcycle.According to the characteristic of the crank-connect rod mechanism of the single-cylinder engine, the mathematical model of two-mass point has been established. Analysis of the model provides the method to calculate engine's inertia force. The excessive balance has been analyzed systematically for the engine of motorcycle in theory. Predict the effect of the key factors influencing the vibration and put forward the relevant designs of vibration damping based on excessive balance system.