Electric control apparatus for four-wheel steering system.

摘要

An electric control apparatus (C) for a four-wheel steering system is designed to calculate a rear wheel steering angle on a basis of a control rule corresponding with a steering mode selected from a plurality of rear wheel steering modes thereby to steer a set of dirigible rear road wheels (RW1, RW2) at the calculated steering angle. The electric control apparatus (C) is further designed to calculate a difference between new and old steering angles calculated when the selected steering mode has been changed to another one of the steering modes and immediately after change of the selected steering mode, to gradually decreasing an absolute value of the calculated difference at a predetermined time interval, to correct the new steering angle in accordance with the absolute value of the calculated difference until the absolute value becomes zero after change of the selected steering mode and to control an actual steering angle of the rear road wheels (RW1, RW2) in accordance with the corrected new steering angle. <IMAGE>