The sub-workspaces for car driving are described. These are elliptical and the fist-ellipse is discussed. It is where fist-centres grasping gearshift handles of conventional motor vehicles or the central control handle sidestick of a conceptual car steered without using a steering wheel are located. Fist-centers distributed in automotive coordinates have a three-dimensional contour, termed the P95 fist-ellipse. A direct anthropometric measurement approach was used to measure the optimum location of fist-centres in class A and B motor vehicles to generate the P95 fist-ellipse. Fifty male and fifty female Chinese motor vehicle drivers aged 18-60 years were involved in the tests. The dimensions of the 95th percentile fist-ellipses derived from class A and class B vehicles were approximately equal to each other. As long as the centre of the gearshift handle is positioned between two parallel planes tangent to the P95 fist-ellipse on both sides, driver satisfaction of 90% could be obtained. The major axis of the P95 fist-ellipse is 129 mm, and the minor axis is 68 mm in side view and 62 mm in plan view. The major axis is outward 25.7 degrees in plan view and down 7.9 degrees in side view. Formulae are given for calculating the P95 fist-ellipse centroid for left hand and right hand drive vehicles.
Abstract