Vehicle fingertip reach controls--human factors recommendations

Interviews were conducted with 405 drivers of cars equipped with fingertip reach controls. A high percentage of finding problems was reported when the horn was mounted on a stalk and also when the turn signal was on a right stalk. Drivers of configurations with two left stalks had a large percentage of inadvertent operation problems for the turn signal and for the headlight beam selector. A laboratory experiment was conducted to evaluate modes of operation for the wiper on/off, wiper speed and washer on/off functions. Subjects performed best when the wiper on/off and speed control were actuated by a rotating had switch. Subjects' reactions to stalk mounted controls were much faster than their reactions to dash mounted controls. Recommendations to eliminate finding and inadvertent operation problems associated with fingertip reach controls are given.