User-Centered Design and Spatially-Distributed Sequential Electrical Stimulation in Cycling for Individuals with Paraplegia

Abstract

Background In this work, we share the enhancements made in our system to take part in the 2020 Cybathlon Global Edition Functional Electrical Stimulation(FES) Bike Race. The main improvements were: first, an overhaul of the system and user interface developed with User-Centered Design principles with remote access to enable telerehabilitation. Second, the implementation and experimental comparison between the traditional single electrode stimulation (SES) and spatially distributed sequential stimulation (SDSS) applied for FES Cycling. Methods We report on the main aspects of the developed system. To evaluate the user perception of the system, we applied a System Usability Scale (SUS) questionnaire. In comparing SDSS and SES, we collected data from one subject in four sessions, each simulating one race in the Cybathlon format.Results User perception measured with SUS indicates a positive outcome in the developed system. The SDSS trials were superior in absolute and average values to SES regarding total distance covered and velocity. We successfully competed in the Cybathlon 2020 Global Edition, finishing in 6th position in the FES Bike Race category. Conclusions The Cybathlon format induced us to put the end-user in the center of our system design principle, which was well perceived. However, further improvements are required if the intention is to progress to a commercial product. The SDSS trials were superior in absolute and average values compared to SES, indicating that this technique enhances the performance of FES Cycling systems. Although, more extensive studies are required to assess these aspects.