Body Powered Standing Wheelchair

Employer: Shiley Ryan AbilityLab

Role: Research Engineer III

Key Design Features:

• Hand track which was used to both drive the chair but also raise and lower the chair

• Automatic safety wheels which retract in the seated position to allow for wheelies and curb clearance, but deployed in the standing position to provide more stability and safety to the user.

• Compact and lightweight were design goals to make it easier for users to load into and out of vehicles if needed.

• 100% mechanical operation to keep weight down (no battery or heavy lifts), make maintenance user friendly, and to improve drive proprioception.

• Optional hydraulic lift and battery installation with quick disconnects. This was to provide more functionality to users who didn't want to always use the hand track to raise and lower the chair.

This project was being led by another engineer in our lab and supported the design and user evaluation work. My contributions are listed below:

• Coordinated with clinicians to design a user testing protocol for evaluating the functionality of the design over currently available models

• Designed mounting hardware and quick-disconnect features for the modular addition of hydraulic press as an alternative to the manual lift system

• Incorporated OTS disc bicycle brake rotors and calipers to increase functionality and stopping power of the chair assembly as well as lock out the wheels for standing/sitting transtions. Designed all mounting features and routing for new brake hardware.

• Assembled and debugged chain drive hand grips and tensioning system

• Designed and debugged safety wheel mechanism which was required in standing mode for increased stability but needed to be automatically stowed in sitting mode for wheelies and curb clearance.