A road surface friction coefficient estimation apparatus for a vehicle includes: a first estimator; a second estimator; and a third estimator. The first estimator estimates a first road surface friction coefficient on a basis of a vehicle information acquired from the vehicle. The second estimator estimates a second road surface friction coefficient on a basis of an external information acquired from an outside of the vehicle. The third estimator estimates a road surface friction coefficient from the first road surface friction coefficient and the second road surface friction coefficient on a basis of a first reliability degree and a second reliability degree, the first reliability degree indicating a reliability of the first road surface friction coefficient, the second reliability degree indicating a reliability of the second road surface friction coefficient.

A system for controlling movement of a vehicle includes a user input device and computing system. The user input device dynamically controls a settings or balance of driving dynamics in a vehicle, and the user input device is configured to receive a manual input from a user. The computing system controls the settings of the vehicle driving dynamics and/or balance of the vehicle, the computing system is in data communication with the user input device and configured to change the driving dynamics balance proportionately to the manual input upon receiving an input command based on the manual input from the user input device.

Example methods for distributing torque in a driveline, and driveline systems are disclosed. In one approach, a baseline torque split may be employed, e.g., in a drive unit. The method may further include detecting a first gradient of a first driving surface that exceeds a threshold amount while the driveline is traversing the first gradient using the baseline torque split. The method may further include modifying the second share of torque with respect to the first share of torque in response to the detection of the first gradient. In some examples, a modification may include increasing an amount of torque being distributed to a secondary axle of the vehicle, while in others a torque bias between the primary and secondary axle may be reduced.

Example methods for distributing torque in a driveline, and driveline systems are disclosed. In one approach, a baseline torque split may be employed, e.g., in a drive unit. The method may further include detecting a first gradient of a first driving surface that exceeds a threshold amount while the driveline is traversing the first gradient using the baseline torque split. The method may further include modifying the second share of torque with respect to the first share of torque in response to the detection of the first gradient. In some examples, a modification may include increasing an amount of torque being distributed to a secondary axle of the vehicle, while in others a torque bias between the primary and secondary axle may be reduced.

A four-wheel drive vehicle includes: (a) main drive wheels and auxiliary drive wheels; (b) a rotating machine as a drive power source; (c) a drive-power distribution clutch configured to allocate a part of a drive power outputted to the main drive wheels from the drive power source, to the auxiliary drive wheels, so as to distribute the drive power to the main drive wheels and the auxiliary drive wheels with a drive-power distribution ratio between the auxiliary drive wheels and the main drive wheels, such that the drive-power distribution ratio is variable with an engaging force of the drive-power distribution clutch being controlled; and (d) a control apparatus configured, when determining that a heat load of the drive-power distribution clutch is large during deceleration running of the vehicle, to limit a regenerative torque of the rotating machine, as compared with when determining that the heat load is small.

According to the method of estimating a maximum road friction coefficient, artificial braking or driving-related control is conducted and a maximum road friction coefficient is estimated based on a difference in wheel speeds between front and rear wheels, compensated for slip of tires.

A vehicle power distribution control method, apparatus and system are provided. The method includes: acquiring an image of a road surface on which a vehicle drives currently, and recognizing, according to the image of the road surface, the type of the road surface on which the vehicle drives currently; starting a corresponding terrain mode in an all-terrain adaptive mode according to the current type of the road surface; determining a power distribution strategy corresponding to the current terrain mode according to a correspondence between terrain modes and preset power distribution strategies; and switching a center differential of the vehicle to a corresponding locking mode according to the current power distribution strategy, and distributing, in the locking mode, torques to front and rear axles of the vehicle according to a torque distribution curve corresponding to the current power distribution strategy. The front and rear axles of a four-wheel drive vehicle can be conveniently provided with adequate torques on different road surfaces.

A vehicle power distribution control method, apparatus and system are provided. The method includes: acquiring an image of a road surface on which a vehicle drives currently, and recognizing, according to the image of the road surface, the type of the road surface on which the vehicle drives currently; starting a corresponding terrain mode in an all-terrain adaptive mode according to the current type of the road surface; determining a power distribution strategy corresponding to the current terrain mode according to a correspondence between terrain modes and preset power distribution strategies; and switching a center differential of the vehicle to a corresponding locking mode according to the current power distribution strategy, and distributing, in the locking mode, torques to front and rear axles of the vehicle according to a torque distribution curve corresponding to the current power distribution strategy. The front and rear axles of a four-wheel drive vehicle can be conveniently provided with adequate torques on different road surfaces.

A control system in a four-wheel-drive motor vehicle for the distribution of drive forces at least from a drive of the motor vehicle to wheels of the first and second axles of the motor vehicle, at least including: a distribution device for distributing the drive forces to the first and second axles; rotation rate sensors for detecting the rotation rate of the two axles and/or the wheels of the motor vehicle, a central control device that is connected to a distribution controller and the sensors and a vehicle communication system, wherein the distribution controller is attached to the distribution unit and performs control both to a setpoint torque and to a setpoint rotation rate, and thus—in a drive-dependent and switchable manner—determines a distribution ratio of the drive forces to be distributed to the first and second axles on the basis of the ratio between the torque and the setpoint torque or between the setpoint rotation rate and the setpoint rotation rate.

A drive switching mechanism of a utility vehicle includes: a two-wheel drive and four-wheel drive switching device that switches between two-wheel drive and four-wheel drive of the utility vehicle; and a control unit that controls the drive switching mechanism. The two-wheel drive and four-wheel drive switching device switches between two-wheel drive and four-wheel drive by using a first clutch. The control unit permits the two-wheel drive and four-wheel drive switching device to switch from two-wheel drive to four-wheel drive when a rotation difference of the first clutch becomes equal to or smaller than a predetermined value.