BS in Mechanical Engineering
Mechanical Engineering Department
The adapted recumbent project was to redesign a disabled veteran’s recumbent bicycle. The main areas of concern were the crank pedal, chain tension, braking and steering system, and ergonomics. Since the customer is an avid biker, this bike will be used often, so the design is based on the ease of repair and replacement. The crank system was redesigned to a lightweight, adjustable part with chain clearance and high strength. The chain tension was improved by replacing the existing single idler wheel/chain tube system with a dual idler wheel system. The dual idler has a titanium sprocket in one of the wheels and a smooth low friction surface for the other wheel. A rear mechanical disc brake was added with a locking brake lever. The locking brake was added to make it easier for the user to get in and out of the seat. A weld was made on the rear seat stay in order to place a bracket for the rear brake calipers. The front hydraulic brakes were replaced with two mechanical disc brakes with mechanical lines routed to a single dual pull lever. Additional custom seat padding was made specifically for this recumbent tricycle. Using closed cell foam in a nylon cover with sewn on straps, the new seat simply attaches to the existing seat for increased comfort. Total cost for the entire project was $1489.86. A cost breakdown for each specific system is provided in the report. Testing for all implemented systems was conducted and verified using the design specifications as stated in the report. All systems have passed specified design criteria.