| Abstrakt: |
In the aim of investigating the influence of various mechanical parameters on wheelchair propulsion efficiency during real life displacements, either outside or inside the laboratory, a wireless wheelchair ergometer (WWE) has been designed, which is able to measure the six components (F[x], F[y], F[z], M[x], M[y], M[z]) of the efforts applied by the subject on right and left handrims and on the seat. Wheelchair's kinematics is measured by two angular potentiometers fixed on rear wheels' axles, a 3-D accelerometer and a Y-axis gyroscope fixed on wheelchair's frame. The 24 signals produced by these sensors are sampled at 500 Hz by a 16-bit A/D conversion card slotted into a mini PC fixed under the seat, and data are then sent to a remote computer using the IEEE 802.11b and TCP/IP wireless protocols. A preliminary study with one able-bodied subject who performed a straightforward 60-m's run on the track of an indoor stadium demonstrated that the WWE allows exploring some unknown aspects of wheelchair locomotion directly on the field. The future results obtained with this original research instrument should provide some answers to the numerous questions encountered by clinicians in their practise, and help wheelchair manufacturers to improve their products. [ABSTRACT FROM AUTHOR] |
