Zf Friedrichshafen Ag

Maik Würthner

Ingo Sauter

Werner Wolfgang

Rachid Mansour

Robert Gronner

Freddy Josef Frombach

Thomas Ascher

Matthias Reisch

Mario Steinborn

Joachim Staudinger

Johannes Kemler

Ulrich Reith

Bertram Wengert

Stefan Kilian

Axel Heitmann

Thea Schlueter

Frieder Norrenberg

Martin Fajfr

Achim Tegen

Wemer Wolfgang

A method for operating a drive train of a motor vehicle, where the drive train includes a drive aggregate, a group transmission connected between the drive aggregate and a drive output, and a separating cutch connected between the drive aggregate and the group transmission. If a speed is lower than a limit value, the separating clutch is opened and for transmission preselection one or all the other sub-transmission(s) is/are changed to a friction-force-locking condition. The separating clutch is then at least partially closed and the drive aggregate is brought to a defined rotation speed. When a friction-force-locking group transmission is required, it is checked whether a starting gearshift or a driver-desired shift for the group transmission is called for and the target rotation speed of the drive aggregate is checked. Depending on the results, the sub-transmission can be synchronized by a transmission brake or by the drive aggregate.

Method and control device for operating a drive train

A method for processing GPS route data of a vehicle is proposed, in which the GPS route data are used for the route guidance of the vehicle along a route (), wherein vehicle positions and an offroad position information or an onroad position information are generated as route data, wherein a vehicle position calculation function for route guidance of the vehicle is used, if erroneous vehicle positions are generated from the GPS route data. Furthermore, a control device for carrying out a method is proposed.

Method for processing GPS route data of a vehicle

Disclosed is a method for determining a position of a motor vehicle by means of a location device of the motor vehicle. First, a first position (x) related to an installation point of the location device in the motor vehicle is determined. In order to determine a position suitable for controlling the motor vehicle, with reference to the said first position (x) a second position (x) related to a center of gravity of the vehicle is determined, in that the first position (x) is offset by a distance (a) between the said installation point of the location device and the center of gravity of the vehicle.

Method, control device and computer program product for determining a position of a motor vehicle

A method for controlling a rolling or a freewheeling mode of a vehicle having a drive-train with an engine, an automatic or automated transmission and controllable means for interrupting force flow in the drive-train. A current vehicle position and a first road stretch, between the current vehicle position and a road stretch section ahead along which a speed limit applies, are determined. While driving with the drive-train engaged, for the road stretch section ahead, a predicted speed variation, if the force flow in the drive-train is interrupted, is calculated and, based this speed variation, a second road stretch is determined which the vehicle, with the force flow interrupted covers, until a value of the predicted speed variation corresponds to a value of the speed limit ahead. With regard to the determined road stretches, a road stretch point for initiating the rolling or freewheeling mode is determined.

Method for controlling a rolling mode or a freewheel mode of a vehicle

A transmission control device () for an automatic or automated transmission (). A shifting strategy of the transmission control device () controls and/or regulates the operation of the transmission () based on driving condition data such as vehicle mass, driving resistance, vehicle inclination, vehicle velocity, vehicle acceleration, engine rotational speed and/or engine torque, and based on data about the driver's wishes. The transmission control device () continuously calculates the driving condition data of the vehicle mass, driving resistance and/or vehicle inclination based on topographic data of a current position of the motor vehicle, and/or the shifting strategy determines a gear change from an actual gear into a target gear based on topographic data of a defined distance ahead of a motor vehicle. The defined distance ahead of the motor vehicle depends on the currently velocity of the vehicle.

Gearbox control device

A method and device for provisionally determining the mass of a vehicle when it is initialized. After initialization of the vehicle, the method determines a vehicle mass value by a static mass determination method and then checks whether this value is within a predetermined tolerance band around the dynamically last-determined vehicle mass value, which has been stored for that purpose. If this is so, and there has in the meantime been no significant change of the vehicle's mass, the previously stored dynamic vehicle mass value is probably more accurate and is used in the determination. Otherwise it can be assumed that the vehicle mass value has changed substantially, and the statically determined vehicle mass value is therefore used until a device for the dynamic determination of a vehicle mass can supply a more accurate vehicle mass value after a short time.

Determination of the mass of a vehicle

A method for determining the driving resistance of a motor vehicle simultaneously with a shift of an automated shift transmission from a load gear to a target gear such that if a difference between a first driving resistance value F_fw_1 and a second driving resistance value F_fw_2 is large, the shift operation can be corrected. The second driving resistance value F_fw_2 is determined during the shift operation. a time interval &#x394;t which contains the traction-force-free phase of the shift, a plurality of acceleration values a_i of the motor vehicle are measured to obtain the minimum acceleration a_min if the shift operation is a traction shift or the maximum acceleration a_max if it is thrust shift. With the mass m of the vehicle, the second driving resistance value F_fw_2 is calculated with one of the formula F_fw_2=&#x2212;m*a_min or F_fw_2=&#x2212;m*a_max.

Method for determining the driving resistance of a motor vehicle

A method of controlling an automatic transmission of a motor vehicle having clutches controlled by an electronic control unit. A transmission rotational speed in an initial transmission stage is determined. If a first transmission shifting rotational speed is reached, the transmission is shifted from the initial transmission stage to a target transmission stage. A target transmission rotational speed of the target transmission stage is then ascertained. A difference is next ascertained between the target transmission rotational speed and a second shifting transmission rotational speed. An initial counter value, of a counter, is determined, which depends on the transmission rotational speed difference. The counter is next caused to carry out counting, from the initial counter value, as time progresses. If and when the counter value reaches zero, the transmission is shifted from the target transmission stage toward the initial transmission stage.

Method for controlling an automatic vehicle transmission in order to reduce back-and-forth shifting

A method for determining a motor vehicle mass which is implemented in conjunction with shifting an automated shift transmission from a current gear to a desired gear. In determining the mass, a value force and movement parameters are determined partly before or after the shift operation and partly during it. For the more rapid and accurate determination of mass, the drive-wheel-related traction force of the drive engine before and after the shift F_zug_vor, F_zug_nach, the longitudinal acceleration of the vehicle before and after the shift, a_zug_vor, a_zug_nach, and the acceleration a_roll determined in the traction-force-free phase during the shift are determined, and from these and in accordance with the equation m=F_zug/(a_zug&#x2212;a_roll), a first mass value m_vor=F_zug_vor/(a_zug_vor&#x2212;a_roll) is calculated for the beginning of the shift and a second mass value m_nach=F_zug_nach/(a_zug_nach&#x2212;a_roll) is calculated for the end of the shift.

Method for determining the mass of a motor vehicle

A seal of an electric machine installed within a motor vehicle drive mechanism with of one of a wet-running oil-cooled disk gearshift element, a multiple disk clutch and a multiple disk brake being accommodated within a free space of a rotor of the electric machine. An oil free annular gap () is formed between the rotor () and the stator () of the electric machine and the annular gap () has a seal () which, at a high rate of rotation by the rotor () and depending on the type of gap seal, seals without touching.

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Friedrichshafen, Germany

Maik Würthner