A target longitudinal force sum/yaw moment setting section is provided which is configured to determine and set a target longitudinal force sum to be exerted on drive wheels by drive sources and a target yaw moment of a vehicle. A failure detection section is provided which is configured to detect occurrence of a failure in the drive source of each of the drive wheels and a drive system including a control system of the drive source. A one-wheel-failure control section is provided which is configured to, when a failure of one of the wheels is detected by the failure detection section, drive the drive sources of all the remaining sound wheels so as to minimize a sum of squares of load factors of the sound wheels and to be matched with the target longitudinal force sum and the target yaw moment that are set.

A vehicle control method includes: acquiring information on acceleration, information on rotational speed of a drive wheel, and information on driving force; after a dropping state where a calculated speed indicative of a vehicle body speed calculated from the rotational speed is less than an estimated speed indicative of a vehicle body speed in a front-rear direction estimated from the acceleration has transitioned to a non-dropping state and a holding period in which the non-dropping state is held has passed, determining whether or not a reset condition to reset the estimated speed is satisfied; when the reset condition is satisfied, determining whether or not the driving force is less than a threshold value; and when the driving force is less than the threshold value, resetting the estimated speed and setting a current value of the calculated speed to a vehicle body initial speed used for estimating the estimated speed.

The control device of a four-wheel drive vehicle is applied to a four-wheel drive vehicle having a differential restriction device which can change a differential restriction degree between a front wheel rotary shaft and a rear wheel rotary shaft, a braking device can separately change a braking force of the front wheels and a braking force of the rear wheels. The control device determines whether a specific state which has a high possibility that a state where a rear wheel slip ratio becomes larger than a front wheel slip ratio is generated occurs assuming that the differential restriction degree is set to a first degree when the differential restriction degree is set to a second degree so as not to allow the differential operation and change the differential restriction degree from the second degree to the first degree when it is determined that the specific state has occurred.

A method for decelerating a vehicle includes actuating an electric brake motor of an electromechanical braking mechanism in an event of a failure of a hydraulic vehicle brake to produce a braking force in an event of a failure of the hydraulic vehicle brake. The method further includes producing a decelerating torque in the drive train of the vehicle in the event of the failure of the hydraulic vehicle brake. The vehicle includes a brake system. The brake system has the hydraulic vehicle brake and the electromechanical braking mechanism with the electric brake motor.

A method of controlling a hybrid electric vehicle including an engine and a first motor connected to main drive wheels and a second motor connected to auxiliary drive wheels includes determining a required torque, in response to a predetermined condition being satisfied, determining a first torque that the second motor is to continuously output based on the required torque and a vehicle speed and determining a second torque that the second motor is to discontinuously output in order to compensate for acceleration loss in a situation in which the acceleration loss occurs based on a state of an engine clutch disposed between the engine and the first motor, a state of a transmission, or the required torque, and determining a final torque of the second motor based on the first and second torques.

A method for preventing damage to a driving system in vehicles may include determining whether a 4-wheel drive vehicle turns based on a steering angle signal, determining, based on an accelerator opening rate signal of the vehicle, whether a maximum torque causing damage to front wheel driveshafts is produced, checking a bump stroke amount of the vehicle and determining whether the front wheel driveshafts are likely to be damaged by a maximum torque transferred to the front wheel driveshafts when the vehicle turns, and lowering, when the front wheel driveshafts are likely to be damaged, a maximum torque of a 4-wheel drive torque applied to the front wheel driveshafts.

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 vehicle orientation control device is provided in a four wheel drive vehicle capable of applying braking and driving force to each of the vehicle wheels. The vehicle orientation control device (24) is provided in a vehicle control device (10) for controlling the four wheel drive vehicle and includes a standard yaw rate calculating unit (25), a yaw rate sensor (22), a target yaw moment calculating unit (26), a braking and driving force commanding unit (15), and a yaw moment control unit (27). The yaw moment control unit (27) includes an allocation ratio varying unit (27a) for continuously changing the front and rear allocation ratio of the yaw moment control torque to be distributed to the front and rear wheels (3) and (2) in dependence on the detected actual yaw rate that is detected by the yaw rate sensor (22).

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.

Methods, systems, and vehicles are provided for mitigating turbulent air for vehicles. In accordance with one embodiment, a vehicle includes one or more downforce elements, one or more sensors, and a processor. The one or more sensors are configured to obtain one or more parameter values for the vehicle during operation of the vehicle. The processor is processor coupled to the one or more sensors, and is configured to at least facilitate determining whether turbulent air for the vehicle is likely using the parameters, and adjusting a downforce for the vehicle, during operation of the vehicle, by providing instructions for controlling the one or more downforce elements when it is determined that turbulent air for the vehicle is likely.