A vehicle drive system includes a slip acquisition unit that acquires that an excessive slip of front wheels or rear wheels has occurred, an addition slip point calculating unit that calculates addition slip points in a time-discrete manner, based on the slip acquisition unit having acquired that the excessive slip has occurred, a cumulative slip point calculating unit that accumulates the addition slip points and calculates a cumulative slip point over time, a drive state switching unit that, switches between 2WD and AWD based on cumulative slip points, and an increase forbidding determination unit that forbids addition or accumulation of the addition slip points, or increase of the cumulative slip points, in a case where a lateral acceleration correlation value that has correlation with lateral acceleration of the vehicle exceeds a lateral acceleration threshold value.

A method and apparatus for controlling traction of a vehicle with independent drives or motors connected to the wheels or other ground engaging apparatuses. Nominal torque allocations can be determined for a set of motors, the motors connected to ground engaging elements and including a front set of motors and a rear set of motors. The nominal torque allocations can be modified based on a lateral differential correction and a fore-aft differential correction to produce modified torque commands and the modified torque commands can be applied to the set of motors.

There is provided a method for determining, by a controller, a road surface based on vehicle data, including: classifying driving conditions of a vehicle into a plurality of cases; applying a learning logic to each of the classified cases according to characteristics of the cases and constructing an inference model for each case; and determining whether a road surface on which the vehicle is running is a high friction road surface or a low friction road surface based on the inference model for each case.

A torque upper limit value changing section increases an upper limit value of a torque instruction value in a powering range in case a rotational speed reduction degree is greater than a reference value and decreases the upper limit value of the torque instruction value in the powering range in case the rotational speed reduction degree is smaller than the reference value.

A system and method of controlling engine clutch engagement during TCS operation of a hybrid vehicle are provided. The method includes determining whether a TCS is operating and upon determining that the TCS is operating, determining a compensation value for early engagement of an engine clutch during the TCS operation based on a difference between a front wheel speed and a rear wheel speed and a slip amount of front wheels. Additionally, the method includes determining whether engagement of the engine clutch is capable of being started based on the compensation value and starting the engine clutch engagement. Since the engagement of the engine clutch is controlled based on the speed of non-drive wheels during TCS operation, the engagement stability of the engine clutch is improved and the amount of time required to engage the engine clutch is decreased.

A torque distribution control system comprises a torsion unit for detecting traction on wheels of a primary driving axle that is continuously engaged with a drive source or a source of torque power. The amount of traction detected is converted to a signal with variable signal strength, the signal strength correlating to the amount of traction detected by the torsion unit. The signal strength capable of being adjusted automatically based on select parameters and/or manually based on a driver's input. And, in response to the signal, actuators engage and control operations of the vehicle such as the drive source, a braking system, and/or an axle clutch, with the level of engagement dependent upon the signal strength.

A torque distribution control system comprises a torsion unit for detecting traction on wheels of a primary driving axle that is continuously engaged with a drive source or a source of torque power. The amount of traction detected is converted to a signal with variable signal strength, the signal strength correlating to the amount of traction detected by the torsion unit. The signal strength capable of being adjusted automatically based on select parameters and/or manually based on a driver's input. And, in response to the signal, actuators engage and control operations of the vehicle such as the drive source, a braking system, and/or an axle clutch, with the level of engagement dependent upon the signal strength.

An apparatus for controlling a vehicle having a motor is provided and includes a driving information sensor that senses driving information of the vehicle including an open value of an APS, an open value of a BPS, a driving wheel speed, a non-driving wheel speed, external temperature, battery temperature, a vehicle speed, and a shift stage. A driving motor generates a driving force and is operated as a power generator when the vehicle coasts to generate electric energy. An ABS that adjusts a braking force applied to a driving wheel. A controller changes a coast regeneration torque subject to regenerative braking by the driving motor when the vehicle is coasting, based on a difference between a driving wheel speed and a non-driving wheel speed, correction temperature determined based on the external temperature and the battery temperature, a friction coefficient of a road, and an operation condition of the ABS.

A work vehicle includes: an engine; a plurality of drive wheels driven by the engine; and an operation controller executes first drive force control that brakes a slipping drive wheel out of the plurality of drive wheels and executes second drive force control that reduces output of the engine in accordance with the slip ratio of the slipping drive wheel during execution of the first drive force control.

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.