The goal of this project was to develop a lightweight and efficient hybrid bicycle design. A series approach to design of the hybrid bicycle was used to allow for more technical advances to be made. This approach required the project to be divided into three subsystems. During this reporting period graduate students were assigned to two subsystems, i.e., the drive line design and composite material design with the intent of assigning a third graduate student to the third subsystem frame member design in the future. A double planetary gear drive was developed to couple the power from the electric motor and bicyclist. The drive was mounted on a typical bicycle frame for evaluation. Efficiency and experimental data is currently being collected. A computer program using a genetic algorithm was developed to efficiently determine engineering properties of composite materials. This program was numerically verified with commercially available software and textbook composite examples.
Insights into the development process were gained during the course of this project. Advantages to the series approach to design in the university environment were found. Higher-risk designs, such as the genetic algorithm, were attempted with less financial burden. Subsystem designers were free to follow different development paths without interference issues from other subsystems.