A regenerative braking system for an electrified vehicle includes a battery system, an electric motor and a regenerative system resistor. The battery system selectively stores and delivers power. The electric motor is powered by the battery system and transfers drive torque to a driveline for propulsion of the vehicle and that selectively directs regenerative power in a first mode to the battery system during regenerative braking. The regenerative system resistor is selectively moveable between a first position during the regenerative braking in the first mode and a second position where regenerative power is directed to the regenerative system resistor and dissipated as heat in a second mode.

A vehicle employing an active aerodynamic control system is described. A method for controlling the active aerodynamic control system includes determining a target acceleration downforce associated with an acceleration request and vehicle speed, determining a target braking downforce associated with a braking request and vehicle speed, and determining a target cornering downforce associated with a cornering request and vehicle speed. A maximum downforce request and a second greatest downforce request of the target acceleration downforce, the target braking downforce, and the target cornering downforce are determined. A preferred front/rear distribution of downforce is determined based upon the maximum downforce request and the second greatest downforce request. The active aerodynamic control system is controlled based upon the preferred front/rear distribution of downforce and the maximum downforce request.

An automobile comprising first and second flaps provided on either side of a centreline on the underside of the automobile is provided. Each flap is deployable from first positions that extend minimally into the flow to respective second positions where each flap extends maximally into the flow of air when the automobile is in motion to reduce the downforce generated by the automobile. A control unit adapted to receive inputs that indicate the dynamic state of the automobile is further provided. The control unit select positions of the first and second flaps depending on the dynamic state to control the downforce generated by the automobile. If the inputs indicate that the automobile is cornering, the positions of the first and second flaps are selected so as to counter roll of the automobile.

An automobile comprising a cooling duct that extends to underneath the automobile to channel cooling air to a component of the automobile when the automobile is in motion is provided. A restriction located within the cooling duct that is moveable from a first position, in which airflow to the component is substantially unimpeded, to a second position in which the airflow to the component is substantially impeded, when the automobile is in motion is further provided. The automobile generates more downforce when the restriction is in the second position versus the first position. A control unit configured to select the position of the restriction to control the downforce generated by the automobile if the temperature of the component is below a predetermined level, and to select the first position for the restriction if the temperature of the component is above the predetermined level, is also provided.

A vehicle employing an active aerodynamic control system is described. A method for controlling the active aerodynamic control system includes determining a target acceleration downforce associated with an acceleration request and vehicle speed, determining a target braking downforce associated with a braking request and vehicle speed, and determining a target cornering downforce associated with a cornering request and vehicle speed. A maximum downforce request and a second greatest downforce request of the target acceleration downforce, the target braking downforce, and the target cornering downforce are determined. A preferred front/rear distribution of downforce is determined based upon the maximum downforce request and the second greatest downforce request. The active aerodynamic control system is controlled based upon the preferred front/rear distribution of downforce and the maximum downforce request.

A vehicle employing an active aerodynamic control system is described. A method for controlling the active aerodynamic control system includes determining a target acceleration downforce associated with an acceleration request and vehicle speed, determining a target braking downforce associated with a braking request and vehicle speed, and determining a target cornering downforce associated with a cornering request and vehicle speed. A maximum downforce request and a second greatest downforce request of the target acceleration downforce, the target braking downforce, and the target cornering downforce are determined. A preferred front/rear distribution of downforce is determined based upon the maximum downforce request and the second greatest downforce request. The active aerodynamic control system is controlled based upon the preferred front/rear distribution of downforce and the maximum downforce request.

A method for controlling an active aerodynamic element in a vehicle having road wheels with tires in contact with a road surface includes receiving driver input signals and vehicle kinematics data. The driver input signals correspond to a requested aerodynamic performance operating point. Tire coefficients of friction in the longitudinal and lateral directions are provided to the controller. Desired longitudinal and lateral forces acting on the tires are determined using the input signals, kinematics data, and actual force data. Additionally, a desired total aerodynamic downforce for meeting the aerodynamic performance operating point is determined as a function of the tire forces and coefficients. A position of the aerodynamic element(s) is controlled such that the total aerodynamic downforce is achieved. A system includes the aerodynamic element(s), actuator(s), and controller. A vehicle includes the body, road wheels, active aerodynamic element(s), actuator(s), and controller.

A method for controlling an active aerodynamic element in a vehicle having road wheels with tires in contact with a road surface includes receiving driver input signals and vehicle kinematics data. The driver input signals correspond to a requested aerodynamic performance operating point. Tire coefficients of friction in the longitudinal and lateral directions are provided to the controller. Desired longitudinal and lateral forces acting on the tires are determined using the input signals, kinematics data, and actual force data. Additionally, a desired total aerodynamic downforce for meeting the aerodynamic performance operating point is determined as a function of the tire forces and coefficients. A position of the aerodynamic element(s) is controlled such that the total aerodynamic downforce is achieved. A system includes the aerodynamic element(s), actuator(s), and controller. A vehicle includes the body, road wheels, active aerodynamic element(s), actuator(s), and controller.

A method of diagnosing a speed brake fault, where the method includes receiving a position signal from the at least one position sensor, determining a variation in the position signal relative to a reference position and diagnosing a fault in the speed brake system based on the variation.

A method of diagnosing a speed brake fault, where the method includes receiving a position signal from the at least one position sensor, determining a variation in the position signal relative to a reference position and diagnosing a fault in the speed brake system based on the variation.