A method and system of determining the instant gradient of a road, taking into account positive and negative drive torque, may be used to select one of a plurality of shift maps for a vehicle automatic transmission. The invention takes into account vehicle retardation due to braking, and permits consistent adoption of a shift map appropriate to the instant gradient.

A method and a corresponding device are provided for preventing an undesired vehicle motion during an automatic switch-off process of a drive machine in a motor vehicle. An automatic switch-off process is initiated by a start-stop apparatus before the standstill is reached if the motor vehicle is braked because of a deceleration request and the speed of the vehicle is less than a specified first speed threshold. A brake pressure of suitable magnitude is caused to be locked-in in the brake system even before the vehicle reaches the standstill if a first signal indicating that the vehicle standstill will soon be reached and a second signal indicating that an inability of the drive machine to operate in a self-sustaining manner will soon be reached are acquired because of an initiated automatic switch-off process of the drive machine.

A method of releasing an Automatic Vehicle Hold (AVH) function of an automotive vehicle equipped with a pedal simulator is provided. During operation of the AVH function, either a first mode for releasing the AVH function by an increase of torque of a power train by depressing the accelerator pedal or a second mode for releasing the AVH function by an increase of torque of the power train by depressing the brake pedal again is selected according to driving conditions.

Automatically controlling the longitudinal dynamics of a vehicle includes ascertaining a state variable dependent on the state of at least one wheel brake, detecting overshoots and/or undershoots of a limiting value of the state variable, ascertaining information about a vehicle traveling ahead, setting at least one control of a feedback control system, and controlling the longitudinal dynamics of the vehicle as a function of the at least one control parameter. A sensing device used to ascertain the state of the at least one wheel brake, another sensing device is used to ascertain information about the vehicle traveling ahead, and an evaluating, setting and controlling unit is used to evaluate the state of the at least one wheel brake and the information about the vehicle traveling ahead for setting the at least one control parameter and for controlling the longitudinal dynamics of the vehicle as a function thereof.

A method of and system for detecting absolute acceleration along various axes relative to a desired movement vector while moving relative to a gravity source includes steps of determining a vertical acceleration, perpendicular to the desired movement vector and substantially anti-parallel to a gravitational acceleration due to the gravity source; determining a longitudinal acceleration, parallel to the desired movement vector and to output at vertical acceleration signal and a longitudinal acceleration signal; determining an inclination of the desired movement vector relative to the gravitational acceleration; and processing the vertical acceleration signal, the longitudinal acceleration signal, and the inclination signal to produce an absolute vertical acceleration signal and an absolute longitudinal acceleration signal.

A vehicle control apparatus includes a generator, a brake system, first and second sensors, first and second deceleration rate setting units, and a power generation torque controller. The first deceleration rate setting unit sets, when a first control mode that decelerates a vehicle on the basis of a brake operation performed by an occupant is executed, an allowable deceleration rate upon deceleration of the vehicle on the basis of a brake operation amount. The second deceleration rate setting unit sets, when a second control mode that decelerates the vehicle on the basis of a situation ahead of the vehicle is executed, the allowable deceleration rate upon deceleration of the vehicle on the basis of a brake fluid pressure. The power generation torque controller controls power generation torque of the generator on the basis of the allowable deceleration rate that is set by the first or second deceleration rate setting unit.

Methods, apparatuses and computer program products for estimating absolute wheel roll radii and/or a vertical compression value of wheels of a vehicle are disclosed, wherein yaw rates of the vehicle, wheel speeds of first and second wheels, and optionally lateral acceleration of the vehicle are measured and used as a basis for the estimation.

Longitudinal acceleration, intended travel angle, wheel speed, and requested drive torque signals are measured for a vehicle. The longitudinal acceleration, intended travel angle, wheel speed, and requested drive torque signals are then evaluated. A brake torque is calculated as a function of a propulsive torque, wherein the propulsive torque is produced by a power source for the vehicle. The brake torque is applied when the longitudinal acceleration signal exceeds a longitudinal acceleration threshold, the intended travel angle signal is between intended travel angle limits, the wheel speed signal is less than a minimum speed threshold, the requested drive torque signal exceeds a requested drive torque threshold, and a torque threshold is exceeded.

An electronic control unit of a vehicle recognizes a shift position based on a user's shift operation and controls a drive device based on the shift position, and an accelerator operation, a brake operation, and a steering operation by the user. When a predetermined abnormality that the shift position is not able to be recognized has occurred, the electronic control unit sets an abnormality-time shift position based on vehicle surroundings information and controls the drive device based on the abnormality-time shift position, the brake operation, and the steering operation.

Systems and methods are provided for determining an optimal point during operation of a hybrid electric vehicle towing a trailer at which the energy that can be recouped through regenerative braking is maximized. Operating conditions or characteristics of the hybrid electric vehicle and the brake characteristics of the trailer are considered in determining the optimal point at which the energy that can be recouped is maximized. At the optimal point at which the energy that can be recouped is maximized, the engine of the hybrid electric vehicle is turned off. Otherwise, the engine of the hybrid electric vehicle is left on.