US 11,939,013 B2
Steering control device
Shinya Kasai, Tokyo (JP); Kotaro Shiino, Hitachinaka (JP); Junya Takahashi, Tokyo (JP); and Masaru Yamasaki, Tokyo (JP)
Assigned to Hitachi Astemo, Ltd, Hitachinaka (JP)
Appl. No. 17/425,379
Filed by Hitachi Astemo, Ltd., Hitachinaka (JP)
PCT Filed Aug. 19, 2019, PCT No. PCT/JP2019/032228
§ 371(c)(1), (2) Date Jul. 23, 2021,
PCT Pub. No. WO2020/166113, PCT Pub. Date Aug. 20, 2020.
Claims priority of application No. 2019-024361 (JP), filed on Feb. 14, 2019.
Prior Publication US 2022/0097758 A1, Mar. 31, 2022
Int. Cl. B62D 6/00 (2006.01)
CPC B62D 6/002 (2013.01) [B62D 6/008 (2013.01); B60W 2540/18 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A steering control device forming a steer-by-wire system, wherein a steering angle and a steering torque generated by a driver on a steering shaft connected to a steering wheel of a vehicle has no direct mechanical connection to a steered angle of a tire of the vehicle, the steering control device comprising:
a steering reaction force calculation unit that controls a reaction force according to a state of the vehicle and/or the steering angle, wherein a minimum value of the reaction force does not become equal to or smaller than a predetermined value; and
a calculation unit that determines the steered angle of the tire based on the steering angle and the steering torque generated on the steering shaft, wherein the calculation unit performs control such that:
(i) in an initial stage of steering, in which the steering angle is equal to or less than a predetermined value, the steered angle is controlled based on the steering torque, and
(ii) the steered angle is controlled based on (a) a parameter different from the steering torque when the steering angle is larger than the predetermined value or (b) a changed steering torque gain from when the steering angle is smaller than the predetermined value.