Embodiments of the present invention provide An electric machine control system for a vehicle, the electric machine control system comprising one or more controllers, wherein the vehicle comprises an electric machine arranged to be selectively coupleable to provide torque to at least one wheel of an axle of the vehicle, the control system comprising input means (330) to receive at least one attribute signal (410-4X0) indicative of one or more attributes of the vehicle (100), output means (340) arranged to output a coupling signal (345) to control coupling of the electric machine to the at least one wheel of the axle (222), and processing means (310) arranged to determine (1310) a coupling state of the electric machine (212) to the at least one wheel of the axle in dependence on the at least one attribute signal, wherein the processing means is arranged to control the output means to output the coupling signal (345) indicative of the determined coupling state, wherein the processing means is arranged to defer (1320, 1330) controlling the output means to output the coupling signal indicative of a change in the coupling state until expiry of a predetermined period of time since a last change in the coupling state indicated by the coupling signal.

Embodiments of the present invention provide An electric machine control system for a vehicle, the electric machine control system comprising one or more controllers, wherein the vehicle comprises an electric machine arranged to be selectively coupleable to provide torque to at least one wheel of an axle of the vehicle, the control system comprising input means (330) to receive at least one attribute signal (410-4X0) indicative of one or more attributes of the vehicle (100), output means (340) arranged to output a coupling signal (345) to control coupling of the electric machine to the at least one wheel of the axle (222), and processing means (310) arranged to determine (1310) a coupling state of the electric machine (212) to the at least one wheel of the axle in dependence on the at least one attribute signal, wherein the processing means is arranged to control the output means to output the coupling signal (345) indicative of the determined coupling state, wherein the processing means is arranged to defer (1320, 1330) controlling the output means to output the coupling signal indicative of a change in the coupling state until expiry of a predetermined period of time since a last change in the coupling state indicated by the coupling signal.

Aspects of the present invention relate to a method (400) and to a control system (208) for controlling at least one electric machine (212, 216) of a vehicle (10) to support diagnostic testing of a vehicle system (30) comprising an internal combustion engine (202), wherein the method (400) comprises: controlling a torque output (420) of the at least one electric machine (212,216) to allow a vehicle drive torque demand (410) to be met while the internal combustion engine (202) is operated within at least one torque threshold (432) for the diagnostic testing or operated at a torque setpoint (438) for the diagnostic testing.

Embodiments of the present invention provide an electric machine control system for a vehicle, the electric machine control system comprising one or more controllers, wherein the vehicle comprises an electric machine arranged to be selectively coupleable to provide torque to at least one wheel of an axle of the vehicle, the control system comprising input means to receive at least one attribute signal indicative of one or more attributes (410, 420, 430) of the vehicle and an efficiency signal (440) indicative of selection of an efficiency-based driving mode, output means arranged to output a coupling signal to control coupling of the electric machine to the at least one wheel of the axle, processing means arranged to determine (1510) a first coupling state of the electric machine to the at least one wheel of the axle in dependence on the at least one attribute signal and to determine (1520) a second coupling state of the electric machine to the at least one wheel of the axle in dependence on the at least one efficiency signal, wherein the processing means is arranged to control (1540) the output means to output the coupling signal indicative of the first and second coupling states when the same, and to output (1550) the coupling signal indicative of the first coupling state when the determined first and second coupling states differ.

Aspects of the present invention relate to a method and to a control system for a vehicle, the method comprising: receiving a torque request for an internal combustion engine configured to mechanically couple to a first axle of the vehicle; determining a shortfall relative to the torque request, dependent on torque providable by the engine; and providing an output to control an electric machine to provide a compensation torque configured to compensate for the shortfall, wherein the electric machine is mechanically coupled to a second axle of the vehicle.

Aspects of the present invention relate to a method and to a control system for a vehicle, the method comprising: determining that a trigger condition is satisfied, wherein satisfaction of the trigger condition is dependent on a vehicle speed of the vehicle relative to at least one threshold speed, the at least one threshold speed having a value corresponding to is vehicle speed no greater than four metres per second; and based at least on the determination, controlling when a mode change between a first operating mode and a second operating mode is performed, wherein in the first operating mode the internal combustion engine is in a disconnected state not configured to provide tractive torque, and an electric machine is configured to provide tractive torque, and wherein in the second operating mode at least the internal combustion engine is in a connected state configured to provide tractive torque.

Aspects of the present invention relate to a method and to a control system for a vehicle, the method comprising: determining that a trigger condition is satisfied, wherein satisfaction of the trigger condition is dependent on a vehicle speed of the vehicle relative to at least one threshold speed, the at least one threshold speed having a value corresponding to is vehicle speed no greater than four metres per second; and based at least on the determination, controlling when a mode change between a first operating mode and a second operating mode is performed, wherein in the first operating mode the internal combustion engine is in a disconnected state not configured to provide tractive torque, and an electric machine is configured to provide tractive torque, and wherein in the second operating mode at least the internal combustion engine is in a connected state configured to provide tractive torque.

An electrified fire fighting vehicle includes a chassis, a cab coupled to the chassis, a body coupled to the chassis, a pump system, and a driveline. The driveline includes a front axle coupled to the chassis, a rear axle coupled to the chassis, an energy storage system, an engine coupled to the chassis, and an electromechanical device coupled to the chassis, the engine, and at least one of the front axle or the rear axle. The driveline is a dual drive driveline such that, during any and all modes of operation of the driveline, the electromechanical device is incapable of or prevented from charging the energy storage system at any time when driven by the engine.

An electrified fire fighting vehicle includes a chassis, a cab coupled to the chassis, a body coupled to the chassis, a pump system, and a driveline. The driveline includes a front axle coupled to the chassis, a rear axle coupled to the chassis, an energy storage system, an engine coupled to the chassis, and an electromechanical device coupled to the chassis, the engine, and at least one of the front axle or the rear axle. The driveline is a dual drive driveline such that, during any and all modes of operation of the driveline, the electromechanical device is incapable of or prevented from charging the energy storage system at any time when driven by the engine.

One axle of a hybrid vehicle is powered by an electric motor while a second axle of the vehicle is powered by a powertrain that includes an internal combustion engine. The electrically driven axle can be controlled in a speed control mode or in a torque control mode based on a driver demanded torque. The speed control mode is used when slip is detected at the electrically driven axle. The torque control mode is used when the electrically driven axle has traction. During a transition between these modes, the rate of change of torque is controlled to a predetermined level to mitigate noise, vibration, and harshness.