P14007: Wheelchair Assist Final Presentation Che-An Lee – Industrial and System Engineer Dan Schuster – Mechanical Engineer Phil Medalie – Mechanical Engineer Tom Elliot – Electrical Engineer Sponsor: Multidisciplinary Senior Design Program

Agenda Project Description Design Concept System Architecture Project Status Test Results Conclusion

Project Description Design a low cost device that maintain the characteristic of a manual wheelchair and prevent the wheelchair to roll back Key Customer Needs and Engineering Metrics:

Design Concept Pawl Brake Disk Bearing Block Ratchet Caliper

Design Concept Cont. Pawl Brake Disk Bearing Block Ratchet Caliper

Design Concept Cont.

1.Left Generator Input Banana Clips 2.Right Generator Input Banana Clips 3.Both Bridge Rectifiers 4.Circuit Breaker Switch 5.Zener Diode 6.Buck-Boost Regulator 5 Volts 7.USB out with USB Circuitry.

System Architecture

Project Status Design meets all customer needs except: Weight (0.5 lbs over) Charging system is not on the chair Unable to test: Maximum weight at 10 degree incline Completed BOM for working prototype Completed all mechanical systems under budget

Test Results

Conclusion Current Results: Demonstrated a cost effective solution for rolling backwards Design maintains important characteristics of a manual wheelchair Generator system succeeded in charging a battery Future Work:  Weight reduction  Universally adaptable to most manual wheelchairs  Incorporate movement assist into design  More efficient generator system to charge batteries at lower speeds

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