YES U CAN – ADAPTIVE CYCLING University of Delaware, Department of Biomedical & Mechanical Engineering, Newark, DE Team Members: Brendan Farrell, David Huegel, Shane Kelly, Zack Rogers, Laura van der Post Advisors : Dr. Steve Timmins & Dr. Jennifer Buckley Drive System Key Highlights: - Two chains and a stepper motor drive the trike via a joystick - 1 st chain: Drive motor sprocket to cassette 2 nd chain: Cassette to the front sprocket - Goal is to allow a quadriplegic (who has no movement in her legs) to exercise Figure 1: Mock-up of stepper drive motor connection Introduction Purpose: Yes U Can is a non-profit organization that creates opportunities for those with physical disabilities to become more active. Customers: 1.Vickie George, CEO and President, is a quadriplegic and suffers from a degenerative form of Multiple Sclerosis 2.Wayne Hunter, YUC engineering consultant, is working with us in developing the drive, braking, and steering systems Braking System 1.A balance bar attaches to all three brake cables (2 from back and 1 from front) 2.A linear actuator with a connected spring will be attached to the balance bar and will help in providing tension in the cables 3.Braking by default system: the brakes are always engaged unless the user provides input through the joystick Figure 6: Model of the complete assembly with all systems incorporated Steering System 1.Utilizes a linear actuator to push and pull on a 3 inch lever arm located at the front of the trike 2.Features a 30 degree turning angle in each direction, which has been calculated to be safe and efficient 3.Clamps are used to connect the linear actuator to the frame of the bike with a clevis attaching to the steering rod The Design The project scope is to prototype an electrically-driven tricycle that allows a quadriplegic to become more physically active The overall design encompasses the following: Linear actuator controlled braking and steering systems Stepper motor drive system Battery powered electrical system Balance bar braking concept Aluminum machined clamping systems FES (Functional Electrical Stimulation) will act as the main drive system with the electrically-driven system serving as a backup Figure 5: YUC – Adaptive Cycling team with Vickie George and Wayne Hunter Figure 2: Mock-up of drive system chain connections on the trike Figure 3: Model of the steering actuator system Acknowledgements Dr. Steve Timmins – YUC Trike Team Advisor Dr. Jennifer Buckley – YUC Assistant Advisor FSAE Team Vickie George & Wayne Hunter – Yes U Can University of Delaware – Mechanical Engineering Figure 4: Model of the clevis attachment clamp to lever rod Electrical 1.Batteries – Four 12V 35Ah batteries will be used to power the bike 2.Proof of concept of electrically-driven systems is demonstrated with a toggle switch 3.A battery pack has been manufactured to store the heavy batteries on the back of the trike Figure 7: Model of the braking system with associated clamps and linear actuator Figure 8: Model of the balance bar concept which provides accurate tension in each brake cable Figure 9: Electrical setup for joystick control of drive stepper motor Metrics & Testing Plan FEA (Finite Element Analysis) – high factors of safety Engineering calculations Physical testing with team members and Vickie Table 1: Wants & needs along with associated metrics and evaluation plans for testing Want/NeedMetricEvaulation Plan SafetyStopping distanceBrake test AffordabilityCostCost analysis Comfort# of sharp objectsRoad testing Durability Time until components need replacement Calculation based on battery capacitance