Three Steered Wheels for Ultimate Economy with Good Handling

A three-wheel car concept is described, in which steering of the front wheels is limited to small angles for packaging reasons, so rear-wheel-steering is needed. Arguments for minimizing weight and aerodynamic drag suggest that this particular configuration is the optimum two-passenger vehicle for maximizing fuel economy. The limitation on steering of the front wheels requires that rear-wheel-steering is dominant in tight turns at low speed. The feasibility of this proposed steering scheme is supported by experimental evidence, as well as by the literature on driver behavior and all-wheel-steering cars. Preliminary tests with a prototype vehicle indicate that rear-wheel-steering alone is sufficient below 10 meters per second (22 mph), which would permit a front steer angle limit of .1 radians (6 degrees).