Methods and systems are provided for controlling yaw of a vehicle while maintaining vehicle speed. In one example, equal and opposite vectoring torques are applied to first and second wheels along with a propulsion torque so that a vehicle yaw moment may be induced without accelerating or decelerating the vehicle.

A method of controlling launch of a vehicle may include checking a start condition of the vehicle by a controller, determining whether only predetermined launch creep control torque is set as additional torque or whether the launch creep control torque and predetermined launch pre control torque are set together as the additional torque according to whether an accelerator pedal is manipulated when the start condition is satisfied, by the controller, setting the additional torque by adding launch slip control torque determined in consideration of a wheel speed difference between opposite driving wheels to the additional torque upon determining that the wheel speed difference is greater than a predetermined reference wheel speed, by the controller, and controlling an electric limited slip differential (eLSD) using the set additional torque, by the controller.

A method for estimation of a vehicle tire force includes: receiving, by a controller of a vehicle, a measured vehicle acceleration of the vehicle; receiving, by the controller, a measured wheel speed and a measured yaw rate of the vehicle; forming, by the controller, inertia matrices based on an inertia of rotating components of the vehicle; calculating torques at corners of the vehicle using the inertia matrices; estimating tire forces of the vehicle based on the measured vehicle acceleration, the measured wheel speed, and the inertia matrices; and controlling, by the controller, the vehicle, based on the plurality of estimated longitudinal and lateral tire forces.

A road surface condition estimation device includes a control circuit, an acquisition circuit and an estimation circuit. The control circuit is configured to control a driving device that is able to independently drive a plurality of wheels. The acquisition circuit is configured to acquire detection results of a plurality of wheel speed sensors that detects rotation speeds of the plurality of wheels respectively. The estimation circuit is configured to calculate a slip ratio for each driving wheel, based on a detection result of a first wheel speed sensor and a detection result of a second wheel sensor. The estimation circuit is configured to estimate a friction coefficient for each region on a road surface that corresponds to the driving wheel, based on the slip ratio.

A drive force control system configured to achieve a yaw rate required by a driver. A first target yaw rate is calculated based on a steering angle, and a second target yaw rate is calculated based on a steering torque. A first target torque of a right wheel and a second target torque of a left wheel are calculated based on a first difference between the first target yaw rate and an actual yaw rate. the first target torque is corrected based on the second target yaw rate and the actual yaw rate to obtain a third target torque, and the second target torque is corrected based on the second target yaw rate and the actual yaw rate to obtain a fourth target torque. A controller transmit signals to the drive unit to achieve the third target torque and to achieve the fourth target torque.

An apparatus for controlling a four-wheel drive vehicle includes a tire friction circle calculator that calculates the size of a tire friction circle of each wheel on the basis of vehicle information including a tire vertical load, a resultant force calculator that calculates the magnitude of a resultant force of tire lateral and longitudinal forces for each wheel, a tire-friction-force usage rate calculator that calculates a tire-friction-force usage rate of each wheel that is the ratio of the magnitude of the resultant force to the size of the tire friction circle, and a driving-braking force adjustment controller that adjusts driving force or braking force applied to each wheel. When the tire-friction-force usage rate of any wheel exceeds a predetermined threshold of less than one, the driving-braking force adjustment controller restrains an increase in the driving force or the braking force of the wheel while increasing the driving force or the braking force of at least one of the other wheels that is selected on the basis of driving operation information indicative of the state of a driving operation by a driver.

A drive force control system to increase a yaw rate greater than the yaw rate achieved by rotating a steering wheel to a maximum angle. A target yaw rate is calculated based on a steering angle of the steering wheel. A first predetermined torque and a second predetermined torque are calculated based on a difference between the target yaw rate and an actual yaw rate. When the steering angle of the steering wheel exceeds a first predetermined angle, a first correction torque to correct the first predetermined torque and a second correction torque to correct the second predetermined torque are calculated n accordance with the steering torque.

Disclosed embodiments include steering circuits utilizing a controllable cross-feed loop between left and right drive motor sides of an articulated power machine to reduce skidding caused by a turning operation in which an articulation actuator changes an articulation joint angle between a front frame member and a rear frame member of the power machine.

A vehicle includes motors each configured to drive a front wheel of the vehicle, an electronic limited slip differential (eLSD) between rear wheels of the vehicle, and a controller to, responsive to vehicle turning and a power of each of the motors being less than a maximum value, alter operation of the motors to increase a difference between the powers. Otherwise, the controller operates the eLSD to bias torque toward one of the rear wheels.

A lane departure prevention system includes a controller configured to control a braking force of vehicle wheels such that a lane departure prevention yaw moment is applied to a vehicle. The controller determines whether there is a likelihood that the vehicle enters a spinning state based on at least one of a difference between an actual yaw rate and a normative yaw rate of the vehicle calculated based on a steering angle, a vehicle speed, and the lane departure prevention yaw moment, and a degree of braking slip of a turning inside wheel when the lane departure prevention yaw moment is a yaw moment for preventing departure of the vehicle from a lane to a turning outside, and applies a spin prevention yaw moment to the vehicle when it is determined that there is a likelihood that the vehicle will enter the spinning state.