Steering-wheel grip force characteristics of drivers as a function of gender, speed, and road condition

Abstract

This paper presents the results of a steering-wheel grip force study of male and female drivers driving an automobile on two different road conditions (smooth and rough asphalt) at two different speeds (45 mph=72 km/h and 65 mph=105 km/h). Thirteen subjects (males and females) participated in this study. The force measurements were made through a custom-made capacitive pressure mapping system wrapped around the steering wheel. Results indicated significantly higher absolute force and net grip force values for the male drivers in comparison to the female drivers. On the other hand, the vehicle speed and the road condition did not significantly affect these response variables. In comparison, the relative value of the driver steering-wheel grip force, expressed as a percentage of the maximum voluntary steering-wheel grip force, and the net relative value of the driving steering-wheel grip force, expressed as a percentage of net maximum voluntary steering-wheel grip force, were not affected significantly by any of the factors. The drivers, on the average, applied their 31% of maximum voluntary steering-wheel grip force, and 21% of net maximum voluntary steering-wheel grip force, intermittently, to the steering wheel, while driving. The capacitive pressure mapping system was found to be a useful method in determining and monitoring the drivers’ grip force while driving. Relevance to Industry The knowledge of steering-wheel grip force characteristics of the drivers may benefit the automobile designers and manufacturers to improve the quality of their products in terms of comfort and driving performance. This study used a capacitive pressure mapping system in obtaining such information and presented the drivers’ grip force characteristics for a sample of drivers.