Rear wheel steering method

Abstract

Abstract PURPOSE:To dissolve weak-kneed feeling of a driver at the early stage of turning and make small a turning radius at a time of low speed travel by steering rear wheels so that the smaller a vehicle speed or the larger front wheel steering angles, the larger the toe-out amount of the rear wheels becomes, at a low speed time when the vehicle speed is below a predetermined value. CONSTITUTION:In a 4WS which controls the rear wheel steering angles of a vehicle according to a vehicle speed and front wheel steering angles gammaf, the rear wheels 18L, 18R of the vehicle are controlled respectively to the toe-outs of steering angles thetarl, thetarr at a low speed time when the vehicle speed is below a predetermined value. The smaller the vehicle speed or the larger front wheel steering angles, the larger the toe-in amount is made to become. At the early stage of turning, each cornering force due to the toe-outed rear wheels is canceled, and a driver is able to feel the same turning traverse acceleration as in a 2 WS, and steering instability due to weak-kneed feeling is dissolved. While turning, at the rear wheels, a load is on a rear wheels' turning outer wheel, thus making small a turning radius as a 4WS and enabling the improvement of turning-roundability.

Inventors

• 👤 Mizuho Sugiyama
• 👤 杉山　瑞穂

Bibliographic Details