Determination of gross weight limit for foldaway powered wheelchairs through isometric and psychophysical strength simulations

Abstract

This study concerns the maximum weight of a powered wheelchair for transfer to and from the trunk of a car by individuals with limited exercise endurance. The loading and unloading of a folded wheelchair from the trunk of a medium size American car was simulated. Both static and dynamic simulations were carried out. The isometric (static) and psychophysical (dynamic) strengths of eight adult males while simulating the loading/unloading activities were measured. The results indicated that: (1) the maximum weight of a powered foldaway wheelchair that individuals can load in the car and unload from the car is much lower than the weight of most commercially available powered wheelchairs, and (2) static simulation of the folded wheelchair loading and unloading activity provides wheelchair weight ceiling that is easily exceeded during the dynamic simulation of the activity. The upper limit on the weight of a foldaway powered wheelchair is provided and implications of this limit on future foldaway powered wheelchair designs are briefly discussed. In addition, the user gender and age effects on the foldaway powered wheelchair weight ceiling are also discussed.

Keywords:

• Isometric strength
• Psychophysical strength
• Foldaway powered wheelchair
• Loading/nloading simulation