Steering control device

Abstract

A steering control apparatus (100) controls a steering mechanism to limit a behavior of a vehicle in the vehicle (10) equipped with the steering mechanism (200) which can independently steer front wheels and rear wheels. The steering control apparatus is provided with: a controlling device for controlling the steering mechanism such that a rudder angle of the front wheels and a rudder angle of the rear wheels are reverse-phased and such that a rudder angle speed of the front wheels is higher than a rudder angle speed of the rear wheels.

Description

technical field [0001] The present invention relates to the technical field of a steering control device for controlling steering of front and rear wheels in a vehicle including a four-wheel steering (4Wheel Steering: 4WS) mechanism capable of steering front and rear wheels. Background technique [0002] As such a steering control device, a device that steers the rear wheels in opposite phases with respect to the front wheels in a vehicle equipped with a 4WS mechanism is known (for example, refer to Patent Documents 1 and 2). [0003] For example, Patent Document 1 discloses a technique for transiently turning the rear wheels in opposite phases with respect to the front wheels at the beginning of a turn of the vehicle. For example, Patent Document 2 discloses a technique for simplifying the system by approximating a transfer function for controlling the steering angle of the front and rear wheels by deleting the quadratic term and including only the first-order term. [000...

AI Technical Summary

Problems solved by technology

[0006] In the case where the rear wheels are steered in opposite phases with respect to the front wheels as described above, for example, when a difference in braking force occurs between the left and right wheels while the vehicle is running, the yaw moment and In the method of yaw moment and lateral force in which the lateral force is stably balanced, the target steering angle of the front and rear wheels is calculated, and when the front and rear wheels are respectively controlled so as to achieve the target steering angle, it is caused by the response of the front wheel side and the rear wheel side Due to differences in characteristics, etc., the steering angle of the front and rear wheels cannot maintain the balance of the yaw moment or lateral force during the transition period until the target steering angle is reached, and there is a technical problem that the stability of the vehicle may deteriorate.

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