Currently, there are not many options available for hospitals to cheaply measure the activity of a manual wheelchair user during wheelchair use. The wheel chair ergometer project addresses this through designing, building and testing a device which will measure the distance, speed and work done on a manual wheelchair by a user.

This project is done in collaboration with Dr. Andrew Nunn at the Royal Talbot Rehabilitation Centre, and is designed primarily to be used for physiotherapy purposes in their spinal rehabilitation centre. The information gathered will enable the tracking and assessment of the rehabilitation process.

Through the use of several sensors, a microprocessor and memory, distance and acceleration parameters will be measured and stored over a period of 24 hours, and then uploaded to a PC via a USB port. Further data processing can then be performed to extract the desired information, such as work done by the user throughout the day.

This project demonstrates a mix of sensor theory, hardware and software design, as well as the bio-mechanics of wheelchair propulsion. Further extensions to the project are envisaged, such as adding body temperature and pulse monitoring. A potential source of error is in accounting for the rolling resistance of the chair. To overcome this, surface identification techniques may be employed to reduce this error.

By keeping the project cheap, easy to use and transferable between wheel chairs it is anticipated that several of these units may be produced and used by the hospital as part of a larger data gathering project.

Felix Liebrich, Terry Williamson,
Dr Lachlan Andrew