An electric power-steering device has a speed-reducing mechanism (17) for reducing the speed of an output shaft (16) of an electric motor (15). The speed-reducing mechanism (17) has an internal gear (39) engaged and rotated with the output shaft (16) and an external gear (40) with which the internal gear (39) internally meshes. A drive pulley (41) rotatable together with the external gear (40) and a driven pulley (42) provided so as to surround a steering shaft are connected by an endless belt (43). Speed reduction is obtained by the internal gear (39) and the external gear (40), and the speed-reducing mechanism (17) as a whole achieves a high reduction ratio without greatly reducing the diameter of the drive pulley (41).

Electric power-steering device

A vehicle steering apparatus is comprised of an assist motor, a steering torque sensor, a steering angle sensor, and a controller. The controller has a torque producing section for estimating a virtual steering model input torque from a torque sensor detection value and a steering angle detection value, a virtual steering model of representing a desired steering characteristic which receives the virtual steering model input torque and outputs a target steering angle of a steering column shaft, and a steering angle servo for controlling an output of the assist motor so that the steering angle detection angle follows the target steering angle.

Vehicle steering apparatus

An electric power steering apparatus has a steering mechanism SM having universal joints 4, 6 in a torque transmitting system, a steering toque detecting unit 14, a steering angle detecting, unit 18, a torque fluctuation detecting unit 43 for detecting a torque fluctuation due to the crossing angle α in the universal joints 4, 6 on the basis of the steering angle θ detected by the steering angle detecting unit 18 and any one of the steering torque T detected by the steering torque detecting unit, a current command value It and self-aligning torque SAT; and a current command value correcting unit 44 for correcting the current command value on the basis of the torque fluctuation detected by the torque fluctuation detecting unit 43 and the steering angle θ detected by the steering angle detecting unit 18.

Electric Power Steering Apparatus

A first ECU 30 detects a steering torque applied to a steering system, estimates a self-aligning torque generated in a front wheel on the basis of the steering torque, and estimates a side force for the front wheel on the basis of lateral acceleration and a yaw rate. The first ECU 30 estimates a grip factor e for the front wheel on the basis of a change of the self-aligning torque to the side force. The first ECU 30 judges whether the grip factor is below a second OS (oversteer) start threshold value. A second ECU 40 controls the transfer ratio according to the vehicle state when the grip factor is less than the second OS start threshold value.

Vehicular steering device

There is provided a vehicle control system capable of ensuring stability even if an ego vehicle runs off a travel path. According to the invention, when yaw moment control is carried out to reduce a formed angle between a travel-path defining line of the travel path, which is recognized from information about an area located in a traveling direction of the ego vehicle, and a traveling-direction virtual line extending from the ego vehicle in the traveling direction, if it is judged that the ego vehicle has departed from the travel-path defining line, the yaw moment control is suspended.

Vehicle control system

PROBLEM TO BE SOLVED: To provide a vehicular integrated control device capable of enhancing the vehicular stability by integrally controlling each actuator of at least two of a steering system, a control system and a drive system at an optimum distribution according to the grip degree of each wheel. SOLUTION: In a vehicle of a four-wheel independent steering system, an electronic control device 11 operates the target yaw rate according to the vehicle speed V and the steering angle, and operates the target vehicle control value based on the target yaw rate and the actual yaw rate γ. The electronic control device 11 estimates the grip degrees e1-e4 of each wheel to the road surface, and sets the distribution ratio of the target vehicular control value to actuators of a steering system, a braking system and a driving system according to the grip degrees of e1-e4 of each wheel. The electronic control device 11 controls the actuators of each system according to the control command value At, the control command value Bt and the control command value Ct distributed according to the distribution ratio. COPYRIGHT: (C)2005,JPO&NCIPI

Vehicular integrated control device

PROBLEM TO BE SOLVED: To precisely estimate a gripping degree expressing a lateral gripping degree for a wheel, and to properly control motion of a vehicle, based on the gripping degree. SOLUTION: Self-aligning torque for front wheels is estimated based on steering torque and steering force by a self-aligning torque estimating means 6, and side force for the front wheels is estimated based on a vehicular state quantity by a side force estimating means 9 (or a slip angle for the front wheel is estimated). The gripping degree for the front wheels is estimated based on a change of the self-aligning torque with respect to the side force (or the front wheel slip angle), in a gripping degree estimating means M12. When the change of the self-aligning torque is judged, a reference self-aligning torque is preferably set, and the gripping degree is preferably estimated based on a comparison result of the self-aligning torque with the reference self-aligning torque. COPYRIGHT: (C)2004,JPO

Device for estimating gripping degree for wheel, and motion controller for vehicle provided with the device

PROBLEM TO BE SOLVED: To provide a conjoint control device of a vehicle capable of controlling the stability of the vehicle from a normal range before entering the friction limit range. SOLUTION: The conjoint control device has a first control means CM1 for estimating the gripping degree of a front wheel based on the change of the self-aligning torque against the side force (or the front wheel slip angle) and executing the closed loop control (gripping degree control) based on the estimated gripping degree, and a second control means CM2 for setting the target vehicle behavior based on the quantity of state of the vehicle VH and executing the closed loop control (vehicle behavior control) based on the deviation between the set target vehicle behavior and the actual vehicle behavior. In the device, the gripping degree control according to the operation of a driver DR is executed in the normal range before the friction limit to maintain the stability of the vehicle. If the gripping degree enters the limit range even if this control is executed, the vehicle behavior control is executed to secure the stability of the vehicle. COPYRIGHT: (C)2004,JPO

Conjoint control device of vehicle

PROBLEM TO BE SOLVED: To easily perform countersteering operation when giving braking force on a so-called μ split road surface in an electric steering controller. SOLUTION: In a steering torque control block B0, steering torque for a steered wheel of a vehicle is controlled in accordance with steering operation. Moreover, in a braking force inference block B1, braking force given to each wheel of the vehicle is inferred to infer a difference in braking force given to right and left wheels in a right and left braking force difference inference block B2 based on the braking force inferred in the block B1. Assist steering torque is given to the steering torque control block B0 by an assist steering torque giving block B3 in accordance with a difference in braking force on the right and left wheels to assist operation when performing countersteering. COPYRIGHT: (C)2004,JPO

Electric steering controller and antiskid controller for vehicle having the same

PROBLEM TO BE SOLVED: To set steering reaction force so as to obtain a good steering feeling. SOLUTION: A steering reaction force command value Tp* having hysteresis characteristics to a steering angle θh is calculated on the basis of the judgment whether the steering wheel is increased in steering or decreased in steering therefrom, the steering angle θh, and vehicle speed V, and an actuator such as a motor is controlled so that the steering reaction force equivalent to the steering reaction force command value Tp* applys on the steering wheel. Since the steering reaction force command value Tp* is calculated on the basis of the judgment whether the steering wheel is increased in steering or decreased in steering and the steering angle θh, an adequate steering reaction force command value Tp* can be calculated even if the resolution of a sensor for detecting the steering angle θh is rough, and the stable steering reaction force command value Tp* can be outputted even in slow steering or keeping steering. As a result, good steering feeling can be obtained. COPYRIGHT: (C)2002,JPO

峰一樅山

Papers

Vehicular integrated control device

Device for estimating gripping degree for wheel, and motion controller for vehicle provided with the device

Conjoint control device of vehicle

Electric steering controller and antiskid controller for vehicle having the same

Steering apparatus and setting method for steering reaction force

峰一 樅山

Papers

Vehicular integrated control device

Device for estimating gripping degree for wheel, and motion controller for vehicle provided with the device

Conjoint control device of vehicle

Electric steering controller and antiskid controller for vehicle having the same

Steering apparatus and setting method for steering reaction force

峰一樅山