A method can be used to control a steer-by-wire steering system for a motor vehicle that has two axles each with two wheels. Two front wheels can be steered by front-wheel steering and two rear wheels can be steered by rear-wheel steering. The motor vehicle includes a single wheel drive that is assigned to one of the two axles and drives the two wheels of the corresponding axle via a differential. The motor vehicle comprises an inboard braking system. The method involves checking the motor vehicle speed and activating rear-axle steering when a motor vehicle speed should be slower than 40 km/hr. With rear-axle steering active, the following steps are performed: deactivating front-wheel steering and rear-wheel steering, determining a reference position of a first steering rod via a reference wheel steering angle, determining a differential drive torque between the rear wheels to reach the reference position via a control unit.

A drive unit for a skid steered vehicle includes a controlled differential positioned between two shafts. The end of each shaft forms an output of the drive unit connected directly to the differential outputs via the shafts. A steer motor is in driveable communication with the differential, and an electric propulsion motor is in driveable communication with the shaft outputs. A gear reduction unit, and optional gear change unit, is positioned between the differential and the electric propulsion motor. The electric propulsion motor, the gear reduction unit and optional gear change unit are connected in a parallel connection with an output of the differential to the shaft outputs. The optional gear change unit includes an epicyclic gear reduction unit having an input and an output which provides drive input from the gear change unit to the shaft. A gear change set has a master gear that receives drive output from the electric propulsion motor, and slave gears which are driven by the master gear via one or more gear chains. A dog clutch slideably engages the input of the gear reduction unit and selectively engages with the master gear or slave gears so that the selected position of the dog clutch determines which gear is engaged.

A multi-mode torque vectoring electric drive axle, including a main motor, an auxiliary motor, a differential, a first half shaft, a second half shaft, a primary reducer, a secondary reducer, a planetary gear set, a dual-gear mechanism and a three-phase actuator. The main motor and the auxiliary motor are respectively connected to input ends of the primary reducer and the secondary reducer. Output ends of the primary reducer and the secondary reducer are respectively connected to a differential housing and an input end of the planetary gear set. Two output ends of the planetary gear set are respectively connected to the three-phase actuator and the dual-gear mechanism. An output end of the dual-gear mechanism is connected to the differential housing. The three-phase actuator is a synchronous shifting mechanism for enabling locking, decoupling of the planetary gear set, and connection to the first half shaft.

A method can be used to control a steer-by-wire steering system for a motor vehicle that has two axles each with two wheels. Two front wheels can be steered by front-wheel steering and two rear wheels can be steered by rear-wheel steering. The motor vehicle includes a single wheel drive that is assigned to one of the two axles and drives the two wheels of the corresponding axle via a differential. The motor vehicle comprises an inboard braking system. The method involves checking the motor vehicle speed and activating rear-axle steering when a motor vehicle speed should be slower than 40 km/hr. With rear-axle steering active, the following steps are performed: deactivating front-wheel steering and rear-wheel steering, determining a reference position of a first steering rod via a reference wheel steering angle, determining a differential drive torque between the rear wheels to reach the reference position via a control unit.

A dual-mode electric drive axle with torque parallel coupling and torque vectoring, including: a main motor, an auxiliary motor, a spur gear differential, a first half shaft, a second half shaft, a primary reducer, a secondary reducer, a dual-planetary gear set mechanism, a first clutch, a second clutch and a primary housing. The main motor and the auxiliary motor are respectively connected to input ends of the primary reducer and the secondary reducer. Output ends of the primary reducer and the secondary reducer are respectively connected to a housing of the spur gear differential and a gear ring of the dual-planetary gear set mechanism. A planet carrier of the dual-planetary gear set mechanism is connected to a sun gear through a first clutch, and a gear ring through a second clutch. A characteristic parameter of the dual-planetary gear set mechanism is 2.

Systems and methods are provided herein for operating an electric vehicle in a vehicle yaw mode. The electric vehicle includes a normal driving mode where the electric vehicle is steered by turning the steerable wheels (e.g., left or right) and vehicle yaw mode where the vehicle controls the torque applied to each wheel. In response to receiving input to initiate vehicle yaw mode and yaw direction, the system determines the inner wheels and the outer wheels and provides forward torque to the outer wheels of the vehicle and backward torque to the inner wheels of the vehicle to rotate the vehicle.

A vehicle includes a powertrain having a powerplant and a clutch that selectively couples the powerplant to an axle. A controller is programmed to, in response to the powertrain being in a power-limiting routine, command a torque to the powerplant based on an error between a target slip of the clutch and a slip of the clutch.

A vehicle includes a rear axle having wheels, friction brakes associated with the wheels, and a driver-actuatable input. A vehicle controller is programmed to, in response to the vehicle being in drift mode and the driver-actuatable input being actuated: command zero torque to the wheels, regardless of a driver-demanded torque, for a duration of time; command engagement of the friction brakes responsive to the duration of time ending; and command torque to the wheels responsive to a speed of the wheels being less than a threshold.

A transmission having an input and first and second output shafts and first and second planetary gear sets. Torque introduced via the input shaft is distributed to the two output shafts in a defined ratio. An element of the first planetary gear set is connected to another element of the second planetary gear set and an element of the second planetary gear set is secured to a rotationally fixed component. A torque vectoring superposition unit has a third planetary gear set. A first element of the third planetary gear set is rotationally fixed to a linking shaft. A second element of the third planetary gear set is connected to a machine rotor. A third element of the third planetary gear set is rotationally fixed to an element of the second planetary gear set, which is fixed to the first output shaft.

A transmission having input and output shafts and planetary gear sets. Each planetary gear set has multiple elements. The input and output shafts and planetary gear sets are designed so torque introduced via the input shaft is distributed to the output shafts in a defined ratio and a sum torque is prevented. An element of a first planetary gear set is rotationally fixed to another element of a second planetary gear set and another element of the second planetary gear set is secured to a rotationally fixed component. A torque vectoring superposition unit has an epicyclic gearing and two switching elements. The epicyclic gearing has four connection shafts. A first connection shaft is rotationally fixed to the linking shaft. A second connection shaft is rotationally fixed to an output shaft of the first planetary gear set. The switching elements secure a third and fourth connection shaft to a fixed component.