Study And Application On The Motorcycle Virtual Prototype Technique

The application of virtual prototype technology to develop the products of motorcycle is an effective way to increase the abilities of technology innovation and development on our own technology through using the experience for reference, assimilating and absorbing the foreign advanced manufacture technology. With the help of virtual prototype technology, during the phase of product design of motorcycle, those performances, which are kinematics, dynamics, strength, stiffness, vibration characteristics, can be proceeded to simulate. Therefore the overall performances are matched and the products are optimized integrally. Consequently it is of great importance to study the virtual prototype technology of motorcycle to shorten the development cycle of product, lower production cost, improve the quality of design and increase the ability of market competition.The dissertation is supported by CNSF project, the science and technology brainstorm project of Chongqing and the Zongshen bloc of Chongqing. It has researched a certain number of key problems of virtual prototype of motorcycle. The research works of this dissertation lay the foundation to the development of motorcycle virtual prototype. They are showed as the followings.1) The structure of virtual prototype design system had been researched systematically. The virtual prototype design system of motorcycle had been established basis on virtual prototype modeling and dynamic design. Also the dissertation had presented that the key technologies to the development of virtual prototype.2) According to the characteristic of the motorcycle cover, of which many aspects had been discussed, such as the process of rebuilding, the disposal and segment of the measurement data, the rebuilding of initial surface, split joint and the evaluation of the quality of surface. The utility method of rebuilding the digital model of motorcycle cover had been summed up, and it was successful applied on four type of motorcycle products development.3) Aim at dynamic analysis modeling low-level efficiency, the method of parameter feature modeling was put forward through the integration-oriented of CAD/CAE, and the parameter feature model of the frame was built. And the research works of this dissertation lay the foundation to shorten the design cycle and realize thereuse of digital model.4) The dynamic design theory and modeling method of the virtual prototype of motorcycle was studied in the dissertation. According to the demand reduced vibration of motorcycle, the dynamic design principle of motorcycle was presented which are frequency design principle and dynamic response design principle.5) Based on the dynamic design method. A balance principle and method was studied to reduce the inertial force of engine. And the results were applied to a type of engine. The inertial force of engine was lessened largely.6) Based on the dynamic design method, the structural dynamic analysis of the frame had also done. And the dynamic response characteristics of the frame were studied under the action of change inertia force of engine. As a results, the theoretical foundation was supplied to optimize structural dynamic characteristic of the frame, realize dynamic characteristics of engine and frame good match, reduced vibration of motorcycle.7) The elastic vibration isolation system of engine was studied. And it had presented an elastic isolation vibration principle and frequency design criterion, established the dynamics model of elastic system of engine, and confirmed the dynamic characteristic parameters of system. And it was applied to reduce vibration of motorcycle. The test results have showed that the elastic vibration isolator can effectively separate the high frequent vibration of engine from the frame, which can efficiently solve the problem of vibration of motorcycle.