A controller for a driving force transmitting apparatus mounted in a four-wheel-drive vehicle, includes: a driving force controller configured to calculate a command torque indicating a driving force to be transmitted to the sub-drive wheels via the driving force transmitting apparatus based on a traveling state of the four-wheel-drive vehicle and a road surface condition, and to control the driving force transmitting apparatus based on the command torque; and a road surface condition determiner configured to determine that the road surface condition is a high- condition when a duration of a non-slipping state where a vehicle speed is equal to or higher than a prescribed value and a slip ratio of each of both the main drive wheels is lower than a prescribed value has become equal to or longer than a prescribed time.

A vehicle driving force control apparatus is mounted in a vehicle that runs by transmitting power from a plurality of drive sources to a plurality of wheels or a plurality of sets of wheels. The vehicle driving force control apparatus includes: a ratio determination unit; and a command unit. The ratio determination unit determines a target ratio at which a required driving force applied to the vehicle is to be distributed to the plurality of wheels or the plurality of sets of wheels. The command unit commands the plurality of drive sources to output power such that driving force distributed in accordance with the target ratio is generated in the plurality of wheels or the plurality of sets of wheels.

Embodiments of the present invention provide a vehicle speed control system operable to cause a vehicle to operate in accordance with a target speed value, the system being further operable automatically to control cross-axle locking means of an axle of the vehicle to cause an increase in resistance to relative rotation of wheels of the axle. Thus, the speed control system may be operable automatically to command the cross-axle locking means to increase the resistance to relative rotation of wheels of the axle without a driver being required to intervene to command assumption of this condition.

A method to control a road vehicle driven by a driver and provided with at least a first drive wheel and a second driver wheel belonging to a same axle, each drive wheel being independently operated by a respective first and second electric motor; the control method comprises the step of controlling the torque delivered by each respective motor to the first drive wheel or to the second drive wheel as a function of a torque requested by the driver and independently of the difference in angular speed between the first and the second wheel.

When a towing vehicle is driven while towing a towed vehicle having driving force, a controller of the towed vehicle determines wheel slip of the towing vehicle based on driving information of the towing vehicle and determines wheel slip of the towed vehicle based on driving information of the towed vehicle, and upon determining that wheel slip of the towing vehicle or the towed vehicle has occurred or upon determining that wheel slip of each of the towing vehicle and the towed vehicle has occurred, control to increase or decrease driving force of the towed vehicle or control to change the driving force distribution ratio between left and right wheels of the towed vehicle is performed, whereby it is possible to improve driving stability and rough road escape performance of the towing vehicle and the towed vehicle.

A driving method of controlling a vehicle is provided to solve the problem of a repeated wheel slip and deterioration of wheel slip control performance due to a roll motion by controlling the driving force of a vehicle by reflecting vertical load information of tires in real time while the vehicle is turning, to a method that can solve the problem of a repeated wheel slip and deterioration of wheel slip control performance due to a roll motion by controlling the driving force of a vehicle by reflecting vertical load information of tires in real time while the vehicle is turning.

A method for controlling propulsion of a heavy-duty vehicle, where the heavy-duty vehicle comprises a differential drive arrangement arranged in connection to a drive axle with a left wheel and a right wheel is provided. The method includes determining a nominal shaft slip corresponding to a desired wheel force to be generated by the drive axle wheels, wherein the nominal shaft slip is indicative of a difference between a current vehicle velocity and a vehicle velocity corresponding to the shaft speed, determining a difference between a speed of the left wheel and a speed of the right wheel, adjusting the nominal shaft slip in dependence of a magnitude of the wheel speed difference to a target shaft slip, and controlling the shaft speed based on the target shaft slip.

A driving force control system for a vehicle is provided to control an output torque of a prime mover and a torque split ratio to right and left wheels to improve stability of the vehicle. A controller is calculates target torques delivered to the right wheel and the left wheel based on a required drive torque and data relating to an attitude of the vehicle, and corrects the target torques based on slip ratios of the wheels. The drive motor is control based on a first current value calculated based on a total torque of the corrected target torques to be delivered the wheels, and the differential motor is controlled based on a second current value calculated based on a difference between the corrected target torques to be delivered to the wheels.

A vehicle control strategy provides for automatically controlled movement from rest with deliberate wheel slip to maximize thrust. Different wheel slip conditions are provided for different terrain types. Wheel slip may be progressively reduced as the vehicle reaches a steady state speed. The strategy may also be implemented to maintain vehicle progress on low friction surfaces. The vehicle driver may be commanded to vary a control input, such as accelerator pedal position.

A method for controlling propulsion of a heavy-duty vehicle includes. configuring a nominal shaft slip of the drive shaft in dependence of a desired longitudinal wheel force to be generated by the driven axle, wherein a shaft slip is indicative of a difference between a current vehicle velocity and a vehicle velocity corresponding to the rotation speed of the drive shaft, obtaining a rotation speed of the left wheel and a rotation speed of the right wheel, as function of a current shaft slip of the driven axle, estimating a peak shaft slip value associated with an open differential peak longitudinal force of the driven axle, based on the current shaft slip and on the corresponding obtained speeds of the left and right wheels, and controlling propulsion of the heavy-duty vehicle unit by setting the current shaft slip of the drive shaft based on the configured nominal shaft slip adjusted in dependence of the estimated peak shaft slip value.