Analysis of Whole-Body Vibration Using Electric Powered Wheelchairs on Surface Transitions

Area of Science:

• Biomechanics and Rehabilitation Engineering
• Human Factors and Ergonomics
• Assistive Technology Research

Background:

• Wheelchair users encounter whole-body vibration (WBV) during daily mobility, particularly on varied urban terrains.
• Limited research exists on WBV exposure for power wheelchair users in everyday environments.
• Surface transitions, like curb-ramps, can create significant WBV due to height differentials, impacting user comfort and health.

Purpose of the Study:

• To analyze WBV exposure in power wheelchairs with passive suspension over surfaces with varying thresholds.
• To evaluate a novel power wheelchair featuring active suspension for mitigating WBV on surface transitions.
• To compare WBV levels between passive and active suspension systems across different surface irregularities.

Main Methods:

• Three power wheelchair configurations were tested: passive suspension, active suspension, and active suspension deactivated.
• Testing involved driving over surfaces with five distinct threshold heights.
• Whole-body vibration, including root-mean-square and vibration-dose-value accelerations, was measured for each condition.

Main Results:

• No significant WBV differences were found among the tested electric power wheelchairs (EPWs) across all surfaces.
• Vibration-dose value increased with higher surface thresholds for the passive suspension system.
• The active suspension system maintained a constant vibration-dose value irrespective of surface threshold height.

Conclusions:

• The novel power wheelchair with active suspension demonstrated comparable WBV performance to the passive suspension system.
• While vibration-dose values varied with surface thresholds, all tested EPWs remained within safe limits defined by ISO 2631-1.
• Active suspension may offer consistent ride comfort by stabilizing vibration levels on challenging urban terrains.