Abstract: A method is described for transmitting program codes to a program memory in a controller, particularly in a motor vehicle, having the following operations: a) connecting an interface in a controller to a programming appliance which contains the program codes, setting all the memory cells of the program memory in the controller to a standard value, compressing the program code in the programming appliance on the basis of a lossless data compression process, transmitting the compressed program code to the controller, decompressing the received program code in the controller, and storing the decompressed program code in the program memory in the controller.

Abstract: A method is described for transmitting program codes to a program memory in a controller, particularly in a motor vehicle, having the following operations: a) connecting an interface in a controller to a programming appliance which contains the program codes, setting all the memory cells of the program memory in the controller to a standard value, compressing the program code in the programming appliance on the basis of a lossless data compression process, transmitting the compressed program code to the controller, decompressing the received program code in the controller, and storing the decompressed program code in the program memory in the controller.

Abstract: In a device for measuring the distance to an obstacle, a second transmission pulse as a control measurement for an ultrasonic distance measurement is transmitted only when an echo signal has been received for a first transmission pulse. In addition, a timing window, within which the expected echo signal falls when it is reflected by an obstacle, is created. In this manner, interference signals are advantageously suppressed and the measuring time is accelerated, so that for an application in a motor vehicle to measure distance, a current measured value is always known while the vehicle velocity and the path covered are taken into consideration.

Abstract: An auxiliary back-up and trailer coupling device for motor vehicles includes ultrasonic sensors mounted on the motor vehicle. The ultrasonic sensors transmit and receive sound waves, and are linked to a control and display device. The device permits the position of a trailer unit that is equipped with a coupling device and arranged behind the motor vehicle to be exactly determined. The trailer is equipped with a coupling device, preferably a tow bar, and has an additional transmitting and receiving ultrasonic sensor.

Abstract: A positioning and navigation system for land vehicles features a simple and memory-conserving route entry method. Routes on maps can be specified by the junctions traversed by the route, so that entering only the junctions in memory uses much less space than prior art digital route storage systems which stored the coordinates of each point along the route. A trip progress information display shows the route vividly by using color or brightness contrast with the rest of the map. Additional direction of travel indications can be given, for example on a Head Up Display reflected off the inside of the windshield within the operator's field of view or by acoustic signals or speech-synthesized announcements. This results in particularly easy-to-follow guide to the driver or operator. Head-up displays on motor vehicles often have double images and interfering reflections on the windshield.

Abstract: A method inputting starting and destination points into an electronic navigation system for motor vehicles in which relevant data of street system maps comprising a street identification character and reference point coordinates with assigned house numbers, are stored in a data storage. When inputting, the street identification character and house number of the starting and destination point are entered, then the data storage is first searched for the street identification character and then for the inputted house number. When there is agreement with a house number of the reference points in the data storage its coordinates are taken over for navigation. When there is a disagreement, the reference points adjacent to it in the data storage are determined and the coordinates of the starting or destination point are determined by means of interpolation and used for navigation (FIG. 20).

Abstract: A method for determining the north direction or the travel direction of a vehicle having an electronic compass is proposed by means of which field disturbances at the magnetometer of the compass, occurring during the navigation drive, are measured and evaluated for avoiding angle errors on the direction indication of the compass. For this purpose, the measurement values (Px, y) of the magnetometer are continuously checked by an evaluating circuit of the navigation system and with a deviation (.DELTA.x, y) of several successive measurement values past a predetermined tolerance range (A) of the locus diagram and a simultaneous angle change of the earth's magnetic field vector, an intervention is effected in the direction indication. In this connection, according to the invention, the rate of change (.DELTA..zeta.

Abstract: A method for determining the direction of the earth field, the north direction and the travelling direction of a vehicle by way of a magnetometer mounted in the vehicle is based on dynamic compensation or updating of interfering field changes. For this purpose, a resultant vector (v.sub.K) is formed from the magnetic field vector (V.sub.M) effective at the magnetometer, the previous hard-magnetic interfering field vector (H.sub.H) and the nominal vector (V.sub.P) determined from the circle diagram (O) of the magnetic field, as interfering field change in accordance with the equation v.sub.K =V.sub.M -v.sub.B -H.sub.H and this vector is weighted with a factor (k<1). The weighted resultant vector (K.times.v.sub.K) is then added to the previous interfering field vector (H.sub.H). Using the new hard-magnetic interfering field vector (H.sub.H'), thus determined, the direction of the earth field is then calculated in known manner and evaluated for navigation.

Abstract: A navigation method for motor vehicles having a display device (10) for representing trip destinations is proposed, in which prior to the beginning of a trip the destination data are input into a memory (12) and during the trip, by means of a composite navigation system (11-14) the instantaneous location of the vehicle with respect to the trip destination is displayed continuously. The navigation method provides that upon attaining the trip destination, the deviations of the input destination from the location, ascertained via the composite navigation, are processed for the calculation of correction values. The correction values are stored in memory, and they serve to update code numbers for distance and direction of the composite navigation system, for subsequent trips.