Emulating Candidate Ankle-foot Prostheses to Inform Prescription

Robotic ankle-foot prostheses can improve walking performance for amputees compared to conventional designs [1], but prescription has been hindered by their high cost and uncertainty about the degree to which individuals will benefit. The typical prescription process cannot well predict how an individual will respond to a device they have never used, as it bases decisions on subjective assessment of an individual's current activity level [2]. We propose a new approach to prescription in which individuals ‘test drive’ candidate devices using a prosthesis emulator while their walking performance is quantitatively assessed and results are distilled to inform prescription decisions [3]. Figure 1: The emulator consists of a lightweight prosthesis actuated through a tether by a powerful motor and controller. Metabolic and heart rate, maximum walking speed, and user satisfaction are measured to assess the emulated behaviors.