Research On Structural Topology Optimization Of Electric Bicycle Frame

Electric bicycle frame is the most important structure, connecting and supporting various components, while bearing various forces and moments, so it must be sufficient reliability. In addition, the frame mass should be minimized, to reduce vehicle's total mass. Thus topology optimization is implied to the electric bicycl design process for a reasonable frame structure. The following research achievements and conclusions have been completed.Based on the electric bike frame finite element mode, static and dynamic characteristics analysis was carried out. From the static loading stress, strain contours and some typical natural frequencies with mode shapes, a preliminary assessment on the frame static and dynamic characteristics was executed.The electric bicycle frame finite element model of topology optimization was established through optimization design software HyperWorks. A flexible coupling dynamic model of the electric bike was established and then dynamic performance test was carried out on typical road condition. Results indicated that the model can be used for dynamic simulation. Dynamic loads of all key points were gained by adding a typical road excitation to electric bike flexible coupling dynamic model, and whose peak value was extracted, which would be used in topology optimization. With analysis of how the key parameters in HyperWorks affected topology optimization result, parameters'appropriate value was obtained. The horizontal force, battery load weight, battery location and other factors'influence on the optimization results was also analyzed. Last the final frame of topology optimization design was completed.Lightweight design for the new model built according to HyperWorks topology optimization results was carried out through HyperWorks'dimension optimization design function. With thickness as design variables, strength as constraints, frame weight as the objective function, dimension optimization design was finished with electric bicycle frame lightweight size.In accordance with the topology optimization, sizing optimization result, the electric bicycle frame was re-established in Solidworks, then strength analysis, modal analysis were carried out. Calculation results showed that the optimization result was effective, providing a reference experience for electric bicycle frame structure design in future.