A method for controlling corrected target hydraulic brake force to be generated by estimating friction coefficient variation depending on a bushing degree of a brake friction material and a season change, may include: determining a hydraulic brake torque required for hydraulic braking according to a driver's request brake torque; converting the hydraulic brake torque into a brake hydraulic pressure by use of a torque factor which is a friction capability of a brake friction material in the hydraulic brake torque; and determining a correction amount of the torque factor according to a season and a bushing degree of the brake friction material, which influences a friction coefficient which is an element of the torque factor.

A method for determining a friction coefficient for a contact between a tire of a vehicle and a roadway. The method includes processing sensor signals in order to generate processed sensor signals. The sensor signals represent state data that are read in at least by at least one detection device and that are correlatable with the friction coefficient. The processed sensor signals represent at least one preliminary friction coefficient. The method also includes ascertaining the friction coefficient using the processed sensor signals and a regression model.

A road friction coefficient of a vehicle is estimated by obtaining substantially contemporaneous values associated with a steering angle for a steered axle of the vehicle, a lateral acceleration, a yaw acceleration, an alignment torque and an axle load on the steered axle; estimating a lateral tire force on the basis of the steering angle, lateral acceleration, and yaw acceleration; deriving a pneumatic trail from the alignment torque and estimated lateral tyre force; and estimating a road friction coefficient from the lateral tire force, the axle load, and the pneumatic trail. In embodiments, the derivation of the road friction coefficient includes evaluating a nonlinear function of the pneumatic trail.

In at least some implementations, a method of estimating road friction, includes determining an actual steering load, determining a nominal steering load as a function of vehicle speed, steering angle, and a nominal road friction value, and comparing the actual steering load to the nominal steering load to determine an estimated road friction. In at least some implementations, the nominal steering load is not determined as a function of vehicle yaw, or vehicle lateral acceleration, or vehicle wheel speed compared to vehicle speed, or vehicle tire compliance or road wheel angle.

Provided is a control apparatus for a vehicle, the control apparatus being configured to determine a road surface μ state of a road in front of the vehicle based on an image of a front region of the vehicle, and change a magnitude of an amount of reduction in a braking force per unit time in accordance with the determined road surface μ state in braking force cancel control executed after hill-hold control

This vehicle braking control device executes automatic braking control to adjust a braking torque on the basis of a vehicle target deceleration value corresponding to a distance between the vehicle and an object in front of the vehicle, and executes anti-skid control to suppress excessive wheel slip by adjusting the braking torque on the basis of a wheel speed. The braking control device calculates an actual deceleration value corresponding to the target deceleration value, and executes feedback control on the basis of the target deceleration value and the actual deceleration value such that the actual deceleration value approaches the target deceleration value. The configuration is such that a control gain of the feedback control is reduced when anti-skid control is executed. Further, the configuration may be such that execution of feedback control is prohibited when anti-skid control is executed.

A steering system for a vehicle, including: a pair of wheel steering devices that respectively steer right and left wheels independently of each other; and a controller configured to control the pair of wheel steering devices, wherein the controller is configured to: determine a standard steering amount of each of the right and left wheels in accordance with a steering request; execute opposite-phase shift steering in which steering amounts of the respective right and left wheels are shifted in mutually opposite directions by respective shift amounts with respect to the standard steering amounts determined respectively for the right and left wheels; and estimate a friction coefficient of a road surface on which the vehicle is running based on steering forces respectively applied to the right and left wheels in the opposite-phase shift steering.

A road surface state estimation device includes a tire-side device and a vehicle-body-side system. The tire-side device is disposed in a tire. The vehicle-body-side system is disposed in a vehicle body. The tire-side device outputs a detection signal corresponding to a magnitude of vibration of the tire, generates road surface data based on the detection signal, and performs data communication with the vehicle-body-side system. The vehicle-body-side system acquires information related to the road surface state, performs the data communication with the tire-side device, transmits vehicle-body-side information indicating that the change in the road surface state occurs to the tire-side device when determining that a change in the road surface state occurs based on the information related to the road surface state, and estimates the road surface state based on the road surface data received by the second transceiver.

Systems and methods are disclosed for estimating slipperiness of a road surface. This estimate may be obtained using an image sensor mounted on a vehicle. The estimated road slipperiness may be utilized when calculating a risk index for the road, or for an area including the road. If a predetermined threshold for slipperiness is exceeded, corrective actions may be taken. For instance, warnings may be generated to human drivers that are in control of driving vehicle, and autonomous vehicles may automatically adjust vehicle speed based upon road slipperiness detected.

A control apparatus for a vehicle includes an addition portion that outputs a post-compensation driver request torque, which is acquired by adding a driving torque (a loss compensation driving torque) lost due to a braking torque provided to a wheel on a low-μ road surface side according to a BLSD request hydraulic pressure calculated by a BLSD request hydraulic pressure calculation processing portion to a driver request torque calculated by a driver request torque calculation processing portion, to a motor.