Influence of the operability on the structure of a competition wheelchair

Abstract

The objective of this study was to investigate influences of the operability on the structure of a competition wheelchair using a manipulability which was obtained from an inverse dynamics analysis. The simulation model was represented by restraining the contact area between the frame and seat of the wheelchair and the body model. The body model was constructed by decreasing strength of trunk muscle. Wheelchair models were constructed by varying the range of axle positions. A hand manipulability α was defined as the angle between the tangential vector of the wheel and the major axis of manipulating force ellipsoid which was available for evaluating a robot arm, and the α was calculated from the posture of the upper limb. This study investigates the relationship between the α and the posture of upper limbs with change of the structure of a competition wheelchair to evaluate the operability. As a result, a few of axle positions have a strong effect on the α which tends to depend on the posture of upper limbs at the beginning of push phase. Therefore, the α has a possibility of evaluating the structure of a competition wheelchair with a view to improve the performance of the wheelchair operation.