This project aims to design and manufacture a durable and accessible electric commuter bike for NYC, focusing on the frame, saddle, and wheels. The final design incorporates design specifications for comfort, weight, cost, stability, and aesthetics. How could I design a bike without knowing how to ride one?! Embark on my journey of designing and learning to love bikes through a design project!
The motivation for the bike frame is to build an aesthetic and structurally strong base that can seamlessly house driver controls and power train components. The frame consists of the head tube, down tube, top tube, seat tube, seat stay, chain stay, and drop outs. The goal is to design and build an electric bike that can carry a 300 lb payload and sustain the new york city road conditions while maintaining rider comfort and ease of riding while remaining under 40lbs.
The frame design optimizes weight, rigidity, and aesthetics to cater to New York City commuters as an alternative for bulky, heavy, and uncomfortable rental options.
Therefore, functionally, the bike must
Fit the battery and motor controller designed by the power train sub-system
Withstand road loading conditions
Fit the wheel and seat tube designed by the rest of the Frame sub-system
House the fork rake, headset, and crankshaft selected by the driver controls sub-system
This final design is an iteration of the previous design as it includes efforts to simplify manufacturing and reduce costs. The first version of this design included more aggressive angles, lengths that were not contiguous with other sub-system components, and unique tube shapes that required more difficult manufacturing processes. The Cooper E-Cycle is built on reusing bike tubes that were abandoned in 41 Cooper Square.
The design process began with market and user research. Working on this bike project meant doing a lot of research on bike mechanics and design which was difficult for someone who had never ridden a bike before. I consulted nearby bike shops, local bike experts, and the shop techs at Cooper to understand every part of the frame from the handlebars to the stays.
To address the function requirements challenges, I took the following approach:
BikeCAD 2D sketching: using open-source bike design software to analyze angles, lengths, and standard dimensions on existing bikes. I used these models to generate 2D bike designs
Literature Review: reading on the methods by which bike designers and manufacturers use to ensure comfortable riding design
3D Design: designing in Fusion360 and Solidworks collaborative to ensure cohesion to final product assembly.
ANSYS Simulation: validating functional requirements on design iterations to ensure that the designs can withstand varying NYC road loading conditions including curbs, pedaling, accidents, and more.
Manufacturing: consulting shop techs to understand what is feasible design for welding and notching. I used the water jet cutter to cut thicker sheets for dropouts and converted 3D sketches to manufacturing plans for welders
The bike design was built over two semesters. The first semester was dedicated to design justifications and the second semester was dedicated to manufacturing and validation.
The frame team delivered a robust frame for the battery team and Cooper Union End of Year show. The parts were assembled with minor adjustments for fittings.
Embarking on this project, despite my lack of prior bike-riding experience, became a personal challenge to prove my versatility in design. I navigated complex requirements, led a team, and learned the intricacies of practical manufacturing considerations. Unlike previous design-centric projects, this experience emphasized the fusion of aesthetics with practical engineering.
The successful testing of the frame at the end-of-year show was a significant milestone, highlighting the capabilities of Cooper students. This project, among my early completions, serves as a testament to my evolving engineering skills. Moving forward, I'm eager to apply these insights and skills to future projects, combining technical expertise with user-centric design.
Notably, this endeavor also coincided with a personal triumph—learning how to ride a bike. This achievement not only enhanced my engineering skills but also deepened my connection to the end-user experience. I look forward to leveraging these experiences in upcoming projects.