Abstract: To supplement an electronic navigation system, for example associated with a locating map storing possible paths of a vehicle, two path sensors are provided, one (10) evaluating vehicle operating data and distance traveled, and the other (12) evaluating position of the vehicle with respect to the geomagnetic field. In accordance with the invention, and in order to eliminate drift errors of the vehicle operating sensor (10) and disturbances of the magnetic field sensed by the magnetic field sensor, the output signals from the vehicle operating sensor are differentiated to eliminate long-term drift, and the output signals from the field sensor are integrated to eliminate short disturbances, both the differentiation as well as the integration steps being carried out with respect to distance traveled and not with respect to time. The respectively differentiated and integrated signals are then combined in an adder (28) for application to a course or navigation computer of standard construction.

Abstract: In a method of and an apparatus for determining the position of a land vehicle by detecting and evaluating driving data and subsequent correction of the position calculated from the driving data by matching with data of a stored, digitized road network, the determination of the position is carried out in a very reliable manner. By dividing the digital road network into meshes defined according to surface area by covering it with a grid. The meshes in which the instantaneous position of the vehicle is located, are selected one after the other proceeding from a starting position, and the position calculated from the driving data is corrected at predetermined intervals to the possible and most probable position through the road network in the respective selected mesh and its proximate surrounding area.

Abstract: In a method for determining a route between a starting point and a destination which are located on a digitally memorized road map, the problem is to perform the necessary calculations for determining the route within a short time, even for extensive road systems. Otherwise, the results could arrive too late and could no longer lend the driver any aid in making a decision. The object is attained by dividing the road map into at least two levels of different grid density and regional size and storing it in memory. A plurality of smaller subregions of fine grid density are assigned to the lower level, and one or more larger subregions of coarser grid density are assigned to the higher level. Beginning with the lower level of the road map, a possible route is then studied; if the results are negative, a transition is made to the next-higher level, until a positive result is attained.

Abstract: A method and a device for target tracking of land vehicles are suggested, in particular for use in heavily meshed city road systems. Thereby, a motor vehicle device is used with an input device for a desired target location and an output device for vehicle instructions. The vehicle location (determination of travel path and travel direction) is carried out by picking up and evaluating the wheel rotations of a nondriven vehicle axis.