The NIHR i4i funded WheelSense project was a collaborative project between Coventry University and 3 NHS Trusts: Birmingham Community Healthcare Trust, Kings College Hospitals Foundation NHS Trust, and Glan Clwyd Hospital.
The project aimed to design, develop and evaluate a system for assessing the stability and performance of wheelchairs before they are released to the client and used in the community.
The resulting system (Figure 13) measures the centre of gravity of the client / wheelchair system and maps the stability points. This information can then be used to inform the tuning of the wheelchair to meet client needs, and used predictively to model the effect of changes to the wheelchair on the performance and stability.
Figure 13 – The Wheelsense® System
Wheelsense® (patent WO2015004454 (A1)) is a computer-based system incorporating force measurement technology within a custom made rig. It calculates the centre of gravity, and maps the stability points of the user-wheelchair system.
The design incorporates:
• A folding platform-based weighing system
• Underlying mathematical modelling and electronics
• Software and graphical user interface.
For portability, the platform was designed as a foldable four quadrant frame linked with suitable hinges so that it could be transported by car and used in a clinic, or out in the community.
The platform senses the wheelchair wheel and castor position and determines dimensional information. The assessment procedure involves 3 easy steps whereby the wheelchair is moved sequentially into position on the platform and sensor data collected.)
The resulting stability mapping is presented to the wheelchair prescriber on a Wi-Fi connected tablet computer to inform their tuning of the wheelchair. The data collected can also be used to predictively model the effect on stability of alterations to the wheelchair, for example adjustment of the wheel, castor, or seat position, or the additional of assistive technology. A visual image is presented that can be used to help educate the client on the limits of stability of their chair.
Discussion and Conclusions
The development of Wheelsense® involved a multi-disciplinary design team including product design, software design, clinical expertise, human factors, engineering and mathematical modelling. The development was guided by a user-centred design process. The project was initially informed by interviews with 15 wheelchair prescribers and an online survey completed by 48 participants. The results led to the specification of user and system requirements that guided subsequent development.
Iterative design has ensured that the elements of the system have been effectively integrated and that the system meets the needs of the users and target market. From the initiation of the project, a stakeholder group was formed comprising of wheelchair users, a carer, and representatives from wheelchair services, manufacturers, and commercial providers. The group met every 6 months providing an opportunity for the research team to feed back progress and the stakeholders to inform the design of the system and future commercialisation plans. The active involvement
of end-users (wheelchair prescribers, wheelchair users) and stakeholders in the design process has been achieved through co-design workshops and design reviews of both hardware and software mock-ups and prototypes.
Towards the end of the project a fully functional prototype was tested within the 3 partner NHS Trusts for a 3 month period. The effectiveness and usability was considered through observations of the system in use; semi-structured interviews with engineers and occupational therapists; surveys of patient and carer experience and usability assessments. The results suggested that the system is regarded as a useful clinical tool and easy to use aside from some minor recommendations for improvement. The prescription process using Wheelsense® is efficient and the displayed results are useful for client and carer education. The positive evaluation results are a testament to the user-centred design process and effective interdisciplinary team working employed during this project.
WheelSense (2015). [online]. Last accessed 19th June 2015 at: http://www.coventry.ac.uk/business/health-design-technology-institute/health-design-technology-institute-research-projects/wheelsense/