A vehicle includes a pair of electric machines each coupled to a laterally-opposing wheel to output a wheel torque. The vehicle also includes a controller programmed to command a combined regenerative braking torque output of the electric machines based on a lesser of a braking torque limit of each individual electric machine. The controller is also programmed to command a regenerative braking torque from each electric machine to be within a predetermined torque threshold of each other in response to a yaw rate exceeding a yaw threshold.

A through the road (TTR) hybridization strategy is proposed to facilitate introduction of hybrid electric vehicle technology in a significant portion of current and expected trucking fleets. In some cases, the technologies can be retrofitted onto an existing vehicle (e.g., a trailer, a tractor-trailer configuration, etc.). In some cases, the technologies can be built into new vehicles. In some cases, one vehicle may be built or retrofitted to operate in tandem with another and provide the hybridization benefits contemplated herein. By supplementing motive forces delivered through a primary drivetrain and fuel-fed engine with supplemental torque delivered at one or more electrically-powered drive axles, improvements in overall fuel efficiency and performance may be delivered, typically without significant redesign of existing components and systems that have been proven in the trucking industry.

A control system that controls a driveline of a motor vehicle to operate in a selected one of a plurality of configurations is configured to receive a brake signal responsive to the application of a braking system. The control system causes the driveline to operate in a second configuration and not a first configuration in dependence at least in part on the brake signal. In the first configuration a first group of one or more wheels and in addition a second group of one or more wheels are arranged to be driven by the driveline, and in the second configuration the first group of one or more wheels and not the second group are arranged to be driven by the driveline.

Methods and systems are provided for operating a hybrid vehicle during operating conditions where vehicle braking is requested. In one example, regenerative braking is allocated to vehicle axles responsive to wheel torques of respective vehicle axles in response to an anti-lock braking system being activated. Additionally, friction braking torque is allocated to vehicle axles responsive to the anti-lock braking system being activated.

A drive train system includes at least one internal combustion engine, at least one generator driven by the internal combustion engine for generating electrical energy, at least one electrical machine electrically connected to the generator, at least one driven front axle and at least one driven rear axle, an automatic or manual transmission located between the internal combustion engine and the respective axles, and at least one epicyclic gear unit. Each of the at least one drive front axle and at least one drive rear axle includes output means and is driven by the internal combustion engine.

A vehicle includes a motor and a controller. The controller is programmed to, responsive to an autonomous braking request and a predicted average braking torque associated with the request having a magnitude less than a powertrain regenerative torque limit, brake the vehicle only with the motor according to a torque profile adapted from a most efficient torque profile of the motor so as to have an average value falling within a specified range of the average braking torque.

Systems and methods for operating a driveline of a hybrid vehicle are presented. In one example, the systems and methods determine a driveline disconnect boost time during vehicle operating conditions when it may be less noticeable. The driveline disconnect boost time may then be used to close a driveline disconnect clutch in a way that may reduce torque disturbances through the driveline.

Methods and systems are provided for enhancing reverse driving torque in a powersplit hybrid electric vehicle powertrain. In one example, a method may include accelerating an engine via a generator functioning as a motor, any number of times, to provide an engine braking torque that may increase a reverse driving torque to enable the vehicle to be propelled in reverse at a vehicle speed above a threshold vehicle speed. In this way, reverse gradability may be improved and customer satisfaction increased.

A through the road (TTR) hybridization strategy is proposed to facilitate introduction of hybrid electric vehicle technology in a significant portion of current and expected trucking fleets. In some cases, the technologies can be retrofitted onto an existing vehicle (e.g., a trailer, a tractor-trailer configuration, etc.). In some cases, the technologies can be built into new vehicles. In some cases, one vehicle may be built or retrofitted to operate in tandem with another and provide the hybridization benefits contemplated herein. By supplementing motive forces delivered through a primary drivetrain and fuel-fed engine with supplemental torque delivered at one or more electrically-powered drive axles, improvements in overall fuel efficiency and performance may be delivered, typically without significant redesign of existing components and systems that have been proven in the trucking industry.

A hybrid vehicle and a braking method thereof are provided. The braking method includes determining a current braking situation based on a brake depth and calculating an amount of braking demanded by a driver corresponding to the brake depth when the current braking situation is a general braking situation. A regenerative braking command is generated to execute regenerative braking and a friction braking command to execute friction braking based on the amount of braking demanded by the driver.