Honda Motor Co., Ltd.

Shoji Hamada

Yuki Endo

Norifumi Tamura

Yoshifumi Banno

Yoshinobu Mukai

A vehicle steering system can keep the comfort of steering feeling for a driver, even in a situation, such as traveling on a cant road or in a crosswind, where a unidirectional-drift behavior of a vehicle occurs, and includes an electric motor, a steering angle sensor, a steering torque sensor, and an EPS_ECU that controls driving power of the electric motor, when the vehicle is traveling straight, based on vehicle information including a steering torque and a steering angle, to perform a control for applying an assist torque to a steering system. The EPS_ECU includes an integrating unit for calculating an integrated torque value obtained by integrating the steering torque, and a steering effort assist controlling unit for performing an anti-unidirectional-drift control over the driving power of the electric motor, when the integrated torque value exceeds the threshold value, so as to cancel the unidirectional-drift behavior of the vehicle.

Vehicle steering system

It is determined whether or not a vehicle is in a first vehicle state based on a detected steering torque and a detected yaw rate (step S), one-side pull is decided if the yaw rate is within a range from 2 deg/sec to 10 deg/sec (step S) for 1 second which is a first predetermined time (step S) since an absolute value of the steering torque becomes 20 Nm or larger in the first vehicle state (step S), then a target current value (one-side response) is generated.

Vehicle steering device

A vehicle steering device including a steering torque detection unit that detects a steering torque, the vehicle steering device controlling an electric current value, which is applied to an electric motor, and applying an assist torque to a steering system based on the steering torque, includes a one-side pull response control unit that detects one-side pull generated at a vehicle, and corrects the current value to restrict the one-side pull. One-side pull response control is restricted or inhibited for a predetermined time after the vehicle ends a turn.

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Wako, Japan

Shoji Hamada