EP0186666B1 - Process for determining the direction of travel of a vehicle, using an electronic compass - Google Patents

Process for determining the direction of travel of a vehicle, using an electronic compass

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Publication number
EP0186666B1
EP0186666B1 EP85901973A EP85901973A EP0186666B1 EP 0186666 B1 EP0186666 B1 EP 0186666B1 EP 85901973 A EP85901973 A EP 85901973A EP 85901973 A EP85901973 A EP 85901973A EP 0186666 B1 EP0186666 B1 EP 0186666B1
Authority
EP
European Patent Office
Prior art keywords
travel
vehicle
magnetometer
vector diagram
locus
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP85901973A
Other languages
German (de)
French (fr)
Other versions
EP0186666A1 (en
Inventor
Günther ALBERTER
Harald Bauer
Gerhard Hettich
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Robert Bosch GmbH
Original Assignee
Robert Bosch GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Robert Bosch GmbH filed Critical Robert Bosch GmbH
Priority to AT85901973T priority Critical patent/ATE40746T1/en
Publication of EP0186666A1 publication Critical patent/EP0186666A1/en
Application granted granted Critical
Publication of EP0186666B1 publication Critical patent/EP0186666B1/en
Expired legal-status Critical Current

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Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
    • G01C17/00—Compasses; Devices for ascertaining true or magnetic north for navigation or surveying purposes
    • G01C17/38—Testing, calibrating, or compensating of compasses

Definitions

  • the invention is based on a method for determining the direction of a vehicle with an electronic compass according to the preamble of the main claim.
  • a known navigation apparatus DE-PS 27 54 888
  • the direction of travel of a vehicle is determined with a two-axis magnetometer, the output signals of which are fed to a correction unit for compensating for magnetic interference fields in the vehicle, by means of which a zero point shift of the output signals and such a proportional change of one of the output signals is made.
  • the interference field vector is taken into account and the proportional change of one of the two magnetometer signals is said to The impact of the vehicle body on the earth field can be compensated. Then, for the measured values of the magnetometer on its X and Y axes, the locus turns by turning the vehicle, the center point of which is shifted from the axis cross with the vector of the interference field and which forms an ellipse due to the proportional change of the signals on one axis whose axes run parallel to the measuring axes.
  • the ellipse is to be transformed into a circle and through the zero point shift, the circle is to be moved into the axis cross, which is checked by a control level in that the signals corrected in this way each have to be squared and add a constant value (Circular equation).
  • a disadvantage of this known solution is that the correction of the. Magnetometer measured values is carried out in an analog arithmetic circuit, which is too imprecise according to the previous technology.
  • interference fields that are constant over time are to be taken into account in this way.
  • Another major disadvantage of the known method is that only an axially parallel displacement from the zero point is taken into account for the elliptical locus of the shielded earth field, whereas in reality such an elliptical locus is also rotated by some amount in the vector diagram.
  • the present invention seeks to determine the direction of the earth's field and the direction of travel of the vehicle as precisely as possible by determining the actual locus of the magnetic field measured by the magnetometer as precisely as possible.
  • the method according to the invention for determining the direction of travel with the characterizing features of the main claim has the advantage that, with the stored measuring points, the computer can calculate the center point shift as well as the shape and rotation of the locus curve in the vector diagram without the need for touch tests. Another advantage is that calibration measurements also compensate for the installation tolerances of the magnetometer and the so-called rejection of the earth's field. In this way, it is possible to determine and display the exact direction of the earth's field or the direction of travel or the direction to a predetermined destination from the current measurements on the magnetometer via the determined locus curve.
  • FIG. 1 shows a block diagram of an electronic compass for determining the direction of travel of a motor vehicle according to the invention
  • FIG. 2 shows a vector diagram with the location curve of the magnetic field measured by the compass
  • FIG. 3 shows a motor vehicle with the vector axes in a calibration position
  • FIG. 5 shows a flow diagram for the mode of operation of the electronic compass according to Figure 1 and Figure 5 shows a three-axis magnetometer of an electronic compass in a schematic representation.
  • FIG. 1 shows the block diagram for an electronic compass which is permanently installed for navigation in a motor vehicle.
  • the electronic compass consists of a sensor 10, an evaluation circuit 11 and a display 12.
  • the sensor 10 which is mounted, for example, in the middle under the roof of a passenger vehicle, contains a magnetometer with time coding.
  • the magnetometer can be a three-axis magnetometer according to FIG. 5 or a two-axis magnetometer, which is accommodated in the sensor together with a power supply and a signal shaping stage for each of the magnetic field probes.
  • the evaluation circuit is essentially implemented by a microcomputer, the input of which is supplied with the sensor signals.
  • the evaluation circuit 11 is in a memory stage 13, an arithmetic stage 14 for calculating the parameters of a locus of the measured magnetic field, a further arithmetic stage 15 for determining the angle between the earth's field and the direction of travel, and in a correction stage 16 Angle correction shown broken down.
  • a fixed directional angle o can be applied via a pushbutton switch 17 correction level 16 can be entered.
  • the computing stage 15 is connected via an output to the display 12, on which the direction of travel can be displayed in addition to further information.
  • FIG. 2 shows the vector diagram for measuring the magnetic field in the motor vehicle with a magnetometer arranged in sensor 10 with two probes, one probe axis x in the direction of travel and the other probe axis y lying transversely to the direction of travel in a horizontal vehicle plane.
  • the X component and the Y component of the magnetic field vector H which results from the size and direction of the magnetic field at the sensor 10, are measured by the two probes.
  • FIG. 3 shows the vector H with respect to the longitudinal axis X o and the axis y o running transversely thereto in the vehicle plane.
  • the magnetic field H measured there is composed of a fixed interference field Hs and the component of the earth field He that is active in the vehicle. Although the actual vector of the magnetic field H lies obliquely in space, it is sufficient for the determination to measure the direction of travel with the sensor 10 only the vector H of the magnetic field projected in the driving plane.
  • FIG. 4 a flow chart, which is cycled through by the evaluation circuit 11.
  • the evaluation circuit 11 After the start 19, at least five - preferably ten measuring points in the vector diagram according to FIG. 2 are first detected by the evaluation circuit 11 in a first program section 20 by turning the vehicle 18 and stored in the memory stage 13.
  • these five measured values result in an elliptical locus 0 which is mathematically determined by five parameters and which can be described with reference to the axis cross of the vector diagram using the following vector equation:
  • T is a tensor (matrix) that contains the influence of the earth's field through shielding and magnetization of the vehicle body.
  • He is the vector of the earth field projected onto the driving plane outside the vehicle and Hs is the vector of the constant interference field projected onto the driving plane, which is predetermined by the shape and structure of the vehicle.
  • This vector equation is an equation with five unknowns, the vector H being known, the tensor containing three unknowns and the vector Hs also having two unknowns.
  • all parameters for the center point shift, the shape and the rotation of the locus 0 are now calculated in the vector diagram on the computing stage i 4 of the evaluation circuit 11 with the aid of the measuring points M1 to M5.
  • the calculation of the locus 0 would be possible from five measuring points, which can be relatively close together. In view of the inaccuracy of the measuring points, however, it is necessary that the first five measuring points in the vector diagram x, y are recorded during the rotation of the vehicle 18 by at least 90 °. However, the locus 0 can be calculated with greater accuracy if eight measuring points are stored in the storage stage 13, one measuring point being stored after each rotation of the vehicle 18 by 45 °. As FIG. 2 shows, the locus curve 0 determined in this way represents an ellipse, which is shifted by the constant interference field vector Hs from the axis origin of the vector diagram x, y and with its axes by the angle ⁇ is rotated.
  • the determined parameters of the locus 0 now become the angle calculated, which indicates the direction of the earth field He with respect to the x-axis of the vector diagram.
  • this angle is still required a correction because it does not take into account the so-called rejection, i.e. the deviation of the direction of the earth's field from the actual north pole.
  • the installation tolerances when mounting the sensor 10 in the vehicle 18 are not taken into account, so that the x-axis of the magnetometer probe lying in the direction of travel does not coincide with the longitudinal axis X o of the vehicle.
  • the vehicle is aligned in a given direction, in the example to the east. This results in an angle ⁇ to the actual north direction, which in the example is 90 °.
  • the predetermined angular size is now entered in the program section 23 into the correction stage 16 of the evaluation circuit 11 according to FIG. 1 by pressing the switch 17.
  • the direction of the earth field He is determined in this vehicle position by the computing stages 14 and 15 on the basis of the ongoing measurements from the locus O and the angle ⁇ ′ that occurs is also entered in the correction stage 16.
  • ⁇ ' gives the Angle at which the earth field He forms with the apparent axis x 'of the vector diagram x', y '.
  • a correction angle ⁇ ⁇ is now formed in the correction stage 16 by using the equation
  • the evaluation circuit 11 now checks whether there is a change in the direction of travel of the vehicle 18 with respect to the direction of the measurement point last stored by a certain angle a on the locus 0 in the vector diagram according to FIG. If this is not the case, the program sections 25 to 28 are cyclically run through and the calculated direction of travel of the vehicle 18 is displayed in each case.
  • a predetermined value a of the direction of travel is exceeded, for example 30 compared to the last stored measurement point in the vector diagram according to FIG. 2
  • a further measurement point is now stored in program step 20 in memory stage 13 and is used to check and correct the parameters of the locus curve 0 determined by the computer in the program section 21 processed. Calibration is no longer necessary since the already determined correction angle ⁇ is now constantly taken into account by the evaluation circuit 11.
  • the sensor 10 is equipped with a magnetometer which is provided with three probes X, Y, Z according to FIG. Of these probes, one lies in the direction of travel of the vehicle, a second perpendicular to the direction of travel and the third perpendicular to the direction of travel.
  • the spatial position, shape and rotation of the locus of the magnetic field H acting on the magnetometer are measured in a spatial vector diagram by at least nine measuring points and recorded and stored by the evaluation circuit for calculating the required parameters.
  • the vehicle must not only in a predetermined direction of travel, but also outside which are still aligned exactly horizontally so that a spatial correction angle can be determined in this case.
  • the invention is not limited to an electronic compass for determining the direction of travel of motor vehicles, since both aircraft and watercraft can be equipped with it.
  • the compass can not only be used to determine the direction of travel, but also very generally for navigating vehicles which, for example, are to be moved from a fixed starting point to a specific destination.
  • a digital path signal is given to the evaluation circuit, for example via a wheel sensor or a signal transmitter on the odometer of the vehicle, which is used together with the determined direction of travel to determine the respective location of the vehicle.
  • the new measured values continuously entered into the storage stage 13 during the journey result in automatic re-calibration, which also takes into account changes in the shape, position and rotation of the locus. This ensures that the influences on the measured magnetic field H, which are caused by switching on electrical consumers in the motor vehicle such as headlights, rear window heating, windshield wipers and the like, or by loading the motor vehicle, are compensated for when calculating the direction of travel.
  • a three-axis magnetometer can also take into account a spatial change in the interference field in all three coordinates and an appropriate error compensation can be carried out.
  • a correspondingly constructed evaluation scarf can be used together with path signals, the respective location height of the vehicle is calculated and output.
  • a specified height base must be entered from time to time,

Landscapes

  • Engineering & Computer Science (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Remote Sensing (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Navigation (AREA)
  • Measuring Magnetic Variables (AREA)

Abstract

A process for determining the direction of travel of a vehicle using an electronic compass consisting of a calculating circuit and a magnetometer firmly fixed to the vehicle. To determine the focus curve (O) of the earth's magnetic field (He) with the magnetometer, five points (M1...M5) measured by the latter by rotation of the vehicle are collected and memorized by the calculation circuit. Using an algorithm with five unknowns the movement parameters of the centre (Hs), the shape (ellipse) and rotation (angle x) of the locus curve (O) are calculated in a vector diagram by the computer on the basis of the five points measured and then the direction of the earth's field (He) is determined. Finally, the vehicle is directed towards a given celestial direction and a correction angle is formed and memorized on the basis of the true direction of the North Pole and that measured by the compass. In the subsequent measurements, account is taken of the correction angle when determining the direction of travel ( phi ) on the basis of the locus curve (O).

Description

Verfahren zur Ermittlung der Fahrtrichtung eines Fahrzeuges mit elektronischen KompaßMethod for determining the direction of travel of a vehicle with an electronic compass
Stand der TechnikState of the art
Die Erfindung geht aus von einem Verfahren zur Ermittlung der Fahrzeugr-ichtung eines Fahrzeuges mit einem elektronischen Kompaß nach der Gattung des Hauptanspruchs. Bei einem bekannten Navigationsapparat (DE-PS 27 54 888) wird die Fahrrichtung eines Fahrzeugs mit einem Zwei-Achsen- Magnetometer ermittelt, dessen Ausgangssignale zur Kompensation von magnetischen Störfeldern im Fahrzeug einer Korrektureinheit zugeführt werden, durch die eine Nullpunktverschiebung der Ausgangssignale s.owie eine proportionale Veränderung eines der Ausgangssignale vorgenommen wird. Bei dieser Lösung geht man davon aus, daß im Fahrzeug ein Störfeld mit einem festen Vektor vorhanden ist, der mit einem Erdfeld überlagert ist, welches durch die Karosserie des Kraftfahrzeuges je nach Ausrichtung des Fahrzeuges mehr oder weniger abgeschirmt wird. Durch die Nullpunktverschiebung wird dabei der Störfeldvektor berücksichtigt und durch die proportionale Veränderung eines der beiden Magnetometersignale soll die Auswirkung der Fahrzeugkarosserie auf das Erdfeld ausgeglichen werden. Danach ergibt sich für die Meßwerte des Magnetometers auf seiner X- und Y-Achse durch Drehen des Fahrzeuges eine Ortskurve, deren Mittelpunkt mit dem Vektor des Störfeldes aus dem Achsenkreuz verschoben ist und die durch die proportionale Veränderung der Signale auf einer Achse eine Ellipse bildet, deren Achsen parallel zu den Meßachsen verlaufen. Durch die proportionale Veränderung des einen Ausgangssignales soll die Ellipse zu einem Kreis umgeformt und durch die Nullpunktverschiebung soll der Kreis ins Achsenkreuz verlegt werden, was durch eine Kontrollstufe dadurch überprüft wird, daß die so korrigierten Signale jeweils zum Quadrat erhoben und addiert einen konstanten Wert bilden müssen (Kreisgleichung).The invention is based on a method for determining the direction of a vehicle with an electronic compass according to the preamble of the main claim. In a known navigation apparatus (DE-PS 27 54 888), the direction of travel of a vehicle is determined with a two-axis magnetometer, the output signals of which are fed to a correction unit for compensating for magnetic interference fields in the vehicle, by means of which a zero point shift of the output signals and such a proportional change of one of the output signals is made. With this solution, it is assumed that an interference field with a fixed vector is present in the vehicle, which is overlaid with an earth field, which is more or less shielded by the body of the motor vehicle depending on the orientation of the vehicle. Due to the zero point shift, the interference field vector is taken into account and the proportional change of one of the two magnetometer signals is said to The impact of the vehicle body on the earth field can be compensated. Then, for the measured values of the magnetometer on its X and Y axes, the locus turns by turning the vehicle, the center point of which is shifted from the axis cross with the vector of the interference field and which forms an ellipse due to the proportional change of the signals on one axis whose axes run parallel to the measuring axes. Through the proportional change of the one output signal, the ellipse is to be transformed into a circle and through the zero point shift, the circle is to be moved into the axis cross, which is checked by a control level in that the signals corrected in this way each have to be squared and add a constant value (Circular equation).
Nachteilig bei dieser bekannten Lösung ist, daß die Korrektur der vom. Magnetometer gemessenen Werte in einer analogen Rechenschaltung durchgeführt wird, was nach der bisherigen Technologie zu ungenau ist. Außerdem ist nicht bekannt, auf welche Weise die Korrekturgrößen ermittelt werden. Da eine Kontrollstufe benötigt wird, ist vielmehr davon auszugehen, daß die Korrekturgrößen durch Tastversuche ermittelt werden müssen, was äußerst umständlich und fehlerhaft ist. Außerdem sind auf diese Weise nur zeitlich konstant e Stδrfelder zu berücks icht igen . Ein weit erer wesentlicher Nachteil des bekannten Verfahrens besteht aber darin, daß für die elliptische Ortskurve des abgeschirmten Erdfeldes lediglich eine achsparallele Verschiebung aus dem Nullpunkt berücksichtigt wird, wogegen in Wirklichkeit eine solche elliptische Ortskurve auch noch im Vektordiagramm um irgendeinen Betrag gedreht ist. Da diese Drehung beim bekannten Meßverfahren nicht erfaßt wird, ergibt sich für eine Navigation eine erhebliche Abweichung der ermitteilen von der tatsächlichen Fahrrichtung. Mit der vorliegenden Erfindung wird angestrebt, durch eine möglichst genaue Ermittlung der tatsächlichen Ortskurve des vom Magnetometer gemessenen Magnetfeldes die Richtung des Erdfeldes bzw. die Fahrrichtung des Fahrzeuges möglichst genau zu ermitteln.A disadvantage of this known solution is that the correction of the. Magnetometer measured values is carried out in an analog arithmetic circuit, which is too imprecise according to the previous technology. In addition, it is not known how the correction variables are determined. Since a control level is required, it can rather be assumed that the correction values have to be determined by touch tests, which is extremely cumbersome and incorrect. In addition, interference fields that are constant over time are to be taken into account in this way. Another major disadvantage of the known method is that only an axially parallel displacement from the zero point is taken into account for the elliptical locus of the shielded earth field, whereas in reality such an elliptical locus is also rotated by some amount in the vector diagram. Since this rotation is not detected in the known measuring method, there is a considerable deviation of the determined from the actual direction of travel for navigation. The present invention seeks to determine the direction of the earth's field and the direction of travel of the vehicle as precisely as possible by determining the actual locus of the magnetic field measured by the magnetometer as precisely as possible.
Vorteile der ErfindungAdvantages of the invention
Das erfindungsgemäße Verfahren zur Ermittlung der Fahrrichtung mit den kennzeichnenden Merkmalen des Hauptanspruchs hat den Vorteil, daß mit den gespeicherten Meßpunkten durch den Rechner sowohl die Mittelpunktsverschiebung als auch die Form und die Drehung der Ortskurve im Vektordiagramm zu errechnen ist, ohne daß dazu Tastversuche benötigt werden. Als weiterer Vorteil ist anzusehen, daß mit einer Eichmessung auch Einbautoleranzen des Magnetometers und die sogenannte Mißweisung des Erdfeldes ausgeglichen werden. Auf diese Weise ist es möglich, aus den laufenden Messungen am Magnetometer über die ermittelte Ortskurve die genaue Richtung des Erdfeldes bzw. der Fahrrichtung oder die Richtung zu einem vorgegebenen Ziel zu ermitteln und anzuzeigen.The method according to the invention for determining the direction of travel with the characterizing features of the main claim has the advantage that, with the stored measuring points, the computer can calculate the center point shift as well as the shape and rotation of the locus curve in the vector diagram without the need for touch tests. Another advantage is that calibration measurements also compensate for the installation tolerances of the magnetometer and the so-called rejection of the earth's field. In this way, it is possible to determine and display the exact direction of the earth's field or the direction of travel or the direction to a predetermined destination from the current measurements on the magnetometer via the determined locus curve.
Durch die in den Unteransprüchen aufgeführten Maßnahmen sind vorteilhafte Weiterbildungen und Verbesserungen der im Hauptanspruch angegebenen Merkmale möglich. Besonders vorteilhaft ist, unter Verwendung eines Mikrocomputers während der Fahrt die Änderungen der Fahrtrichtung durch Messung des Magnetfeldvektors von der Auswerteschaltung zu erfassen und beim Überschreiten eines vorgegebenen Wertes der Fahrrichtungsänderung einen weiteren Meßpunkt der Ortskurve im Vektordiagramm abzuspeichern. Die so eingelesenen weiteren Meßpunkte werden zur Überprüfung und Korrektur der ermittelten Parameter der Ortskurve vom Rechner weiter verarbeitet. Außerdem können die Werte für die Fahrrichtungsänderung zusammen mit Wegsignalen des Kraftfahrzeuges zur genauen Ortsbestimmung des Fahrzeuges verwendet werden. Um aus den ersten fünf bis zehn Meßpunkten im Vektordiagramm bereits annähernd die Parameter der Ortskurve berechnen zu können, ist es zweckmäßig das Fahrzeug während der Messungen um mindestens 90º zu drehen.Advantageous further developments and improvements of the features specified in the main claim are possible through the measures listed in the subclaims. It is particularly advantageous to use a microcomputer to record the changes in the direction of travel by measuring the magnetic field vector from the evaluation circuit and to store a further measurement point of the locus curve in the vector diagram when a predetermined value of the change in direction of travel is exceeded. The further measuring points read in in this way are further processed by the computer for checking and correcting the determined parameters of the locus curve. In addition, the values be used for changing the direction of travel together with path signals of the motor vehicle for the exact location of the vehicle. In order to be able to approximately calculate the parameters of the locus curve from the first five to ten measuring points in the vector diagram, it is advisable to turn the vehicle by at least 90 ° during the measurements.
Zeichnungdrawing
Ein Ausführungsbeispiel der Erfindung ist in der Zeichnung dargestellt und in der nachfolgenden Beschreibung näher erläutert. Es zeigen Figur 1 ein Blockschaltbild eines elektronischen Kompasses zur erfindungsgemäßen Ermittlung der Fahrrichtung eines Kraftfahrzeuges, Figur 2 ein Vektordiagramm mit der Ortskurve des vom Kompaß gemessenen Magnetfeldes, Figur 3 zeigt ein Kraftfahrzeug mit den Vektorachsen in einer Eichstellung, Figur 5 zeigt ein Flußdiagramm für die Arbeitsweise des elektronischen Kompasses nach Figur 1 und Figur 5 zeigt ein Drei-Achsen-Magnetometers eines elektronischen Kompasses in schematischer Darstellung.An embodiment of the invention is shown in the drawing and explained in more detail in the following description. 1 shows a block diagram of an electronic compass for determining the direction of travel of a motor vehicle according to the invention, FIG. 2 shows a vector diagram with the location curve of the magnetic field measured by the compass, FIG. 3 shows a motor vehicle with the vector axes in a calibration position, and FIG. 5 shows a flow diagram for the mode of operation of the electronic compass according to Figure 1 and Figure 5 shows a three-axis magnetometer of an electronic compass in a schematic representation.
Beschreibung des AusführungsbeispielesDescription of the embodiment
In Figur 1 ist das Blockschaltbild für einen elektronischen Kompaß dargestellt, der zur Navigation in einem Kraftfahrzeug fest eingebaut ist. Der elektronische Kompaß besteht aus einem Sensor 10, einer Auswerteschaltung 11 und.einer Anzeige 12. Der Sensor 10, der beispielsweise mitten unter dem Dach eines Personenfahrzeuges angebracht ist, enthält ein Magnetometer mit Zeitverschlüsselung. Das Magnetometer kann dabei ein Drei-Achsen-Magnetometer gemäß Figur 5 oder ein Zwei-Achsen-Magnetometer sein, welches zusammen mit einer Stromversorgung und einer Signalformerstufe für jede der Magnetfeldsonden im Sensor untergebracht ist. Die Auswerteschaltung wird im wesentlichen durch einen Mikrocomputer realisiert, dessen Eingang die Sensorsignale zugeführt werden. Zur besseren Veranschaulichung des Verfahrens zur Ermittlung der Fahrrichtung des Fahrzeuges ist die Auswerteschaltung 11 in eine Speicherstufe 13, eine Rechenst_ufe 14 für die Berechnung der Parameter einer Ortskurve des gemessenen Magnetfeldes, eine weitere Rechenstufe 15 zur Winkelbestimmung zwischen Erdfeld und Fahrrichtung sowie in eine Korrekturstufe 16 zur Winkelkorrektur aufgegliedert dargestellt. Über einen Tastschalter 17 kann dabei ein fester Richtungswinkel o an der Korrekturstufe 16 eingegeben werden. Über einen Ausgang ist die Rechenstufe 15 mit der Anzeige 12 verbunden, auf der neben weiteren Informationen die Fahrrichtung angezeigt werden kann.FIG. 1 shows the block diagram for an electronic compass which is permanently installed for navigation in a motor vehicle. The electronic compass consists of a sensor 10, an evaluation circuit 11 and a display 12. The sensor 10, which is mounted, for example, in the middle under the roof of a passenger vehicle, contains a magnetometer with time coding. The magnetometer can be a three-axis magnetometer according to FIG. 5 or a two-axis magnetometer, which is accommodated in the sensor together with a power supply and a signal shaping stage for each of the magnetic field probes. The evaluation circuit is essentially implemented by a microcomputer, the input of which is supplied with the sensor signals. To better illustrate the method for determining the direction of travel of the vehicle, the evaluation circuit 11 is in a memory stage 13, an arithmetic stage 14 for calculating the parameters of a locus of the measured magnetic field, a further arithmetic stage 15 for determining the angle between the earth's field and the direction of travel, and in a correction stage 16 Angle correction shown broken down. A fixed directional angle o can be applied via a pushbutton switch 17 correction level 16 can be entered. The computing stage 15 is connected via an output to the display 12, on which the direction of travel can be displayed in addition to further information.
Mit Hilfe der Figuren 2, 3 und 4 soll nunmehr die Durchführung des erfindungsgemäßen Verfahrens zur Ermittlung der Fahrrichtung eines Fahrzeuges erläutert werden. Figur 2 zeigt das Vektordiagramm zur Messung des Magnetfeldes im Kraftfahrzeug mit einem im Sensor 10 angeordneten Magnetometer mit zwei Sonden, deren eine Sondenachse x in Fahrrichtung und deren andere Sondenachse y quer zur Fahrrichtung in einer waagerechten Fahrzeugebene liegt. Von den beiden Sonden werden jeweils die X-Komponente bzw. die Y-Komponente des Magnetfeldvektors H gemessen, der sich aus der Größe und Richtung des Magnetfeldes am Sensor 10 ergibt. In Figur 3 ist der Vektor H in bezug auf die Längsachse Xo und die quer dazu in der Fahrzeugebene verlaufene Achse yo dargestellt. Dabei ist angenommen, daß hier der Sensor 10 mitten unter dem Dach des Personenwagens 18 angeordnet ist. Das dort gemessene Magnetfeld H setzt sich zusammen aus einem festen Störfeld Hs und der im Fahrzeug wirksamen Komponente des Erdfeldes He . Obwohl der tatsächliche Vektor des Magnetfeldes H schräg im Raum liegt, genügt es zur Bestimmung der Fahrrichtung mit dem Sensor 10 nur den in der Fahrebene projizierten Vektor H des Magnetfeldes zu messen.With the help of Figures 2, 3 and 4, the implementation of the inventive method for determining the direction of travel of a vehicle will now be explained. FIG. 2 shows the vector diagram for measuring the magnetic field in the motor vehicle with a magnetometer arranged in sensor 10 with two probes, one probe axis x in the direction of travel and the other probe axis y lying transversely to the direction of travel in a horizontal vehicle plane. The X component and the Y component of the magnetic field vector H, which results from the size and direction of the magnetic field at the sensor 10, are measured by the two probes. FIG. 3 shows the vector H with respect to the longitudinal axis X o and the axis y o running transversely thereto in the vehicle plane. It is assumed here that the sensor 10 is arranged in the middle under the roof of the passenger car 18. The magnetic field H measured there is composed of a fixed interference field Hs and the component of the earth field He that is active in the vehicle. Although the actual vector of the magnetic field H lies obliquely in space, it is sufficient for the determination to measure the direction of travel with the sensor 10 only the vector H of the magnetic field projected in the driving plane.
Zur Ermittlung der Fahrrichtung ist es erforderlich, aus dem gemessenen Magnetfeldvektor H die Richtung des Erdfeldes He zu finden. Zu diesem Zweck sind verschiedene aufeinanderfolgende Verfahrensschritte erforderlich, die in Figur 4 in einem Flußdiagramm dargestellt sind, das von der Auswerteschaltung 11 zyklisch durchlaufen wird. Nach dem Start 19 werden zunächst in einem ersten Programmabschnitt 20 mindestens fünf - vorzugsweise zehn Meßpunkte im Vektordiagramm nach Figur 2 durch Drehen des Fahrzeuges 18 von der Auswerteschaltung 11 erfaßt und in der Speicherstufe 13 abgelegt. Im Beispielsfall sind dies die Meßpunkte M1 bis M5, die jeweils nach einer Drehung des Fahrzeuges 18 um etwa 30 vom Sensor 10 gemessen werden. Aus diesen fünf Meßwerten ergibt sich gemäß Figur 2 eine durch fünf Parameter mathematisch festgelegte elliptische Ortskurve 0, die bezogen auf das Achsenkreuz des Vektordiagramms durch folgende Vektorgleichung zu beschreiben ist:To determine the direction of travel, it is necessary to find the direction of the earth's field He from the measured magnetic field vector H. For this purpose, various successive method steps are required, which are shown in FIG. 4 in a flow chart, which is cycled through by the evaluation circuit 11. After the start 19, at least five - preferably ten measuring points in the vector diagram according to FIG. 2 are first detected by the evaluation circuit 11 in a first program section 20 by turning the vehicle 18 and stored in the memory stage 13. In the example, these are the measuring points M1 to M5, each of which is measured by the sensor 10 after the vehicle 18 has been rotated by approximately 30. According to FIG. 2, these five measured values result in an elliptical locus 0 which is mathematically determined by five parameters and which can be described with reference to the axis cross of the vector diagram using the following vector equation:
H = (T . He) + HsH = (T. He) + Hs
dabei ist T ein Tensor (Matrix), der die Beeinflussung des Erdfeldes durch Abschirmung und Magnetisierung der Fahrzeugkarosserie enthält. He ist der Vektor des auf die Fahrebene projizierten Erdfeldes außerhalb des Fahrzeuges und Hs ist der Vektor des auf die Fahrebene projizierten konstanten Störfeldes, das durch die Form und den Aufbau des Fahrzeuges vorgegeben ist. Diese Vektorgleichung ist eine Gleichung mit fünf Unbekannten, wobei der Vektor H bekannt ist, der Tensor drei Unbekannte enthält und der Vektor Hs ebenfalls zwei Unbekannte aufweist. Im nachfolgenden Programmabschnitt 21 werden nun an der Rechenstufe i 4 der Auswerteschaltung 11 mit Hilfe der Meßpunkte M1 bis M5 sämtliche Parameter für die Mittelpunktverschiebung, die Form und die Drehung der Ortskurve 0 im Vektordiagramm errechnet. Theoretisch wäre dabei die Berechnung der Ortskurve 0 aus fünf Meßpunkten möglich, die relativ dicht beieinander liegen können. Im Hinblick auf die Ungenauigkeit der Meßpunkte ist es jedoch erforderlich, daß die ersten fünf Meßpunkte im Vektordiagramm x, y während der Drehung des Fahrzeuges 18 um mindestens 90º erfaßt werden. Mit höherer Genauigkeit läßt sich jedoch die Ortskurve 0 dann berechnen, wenn acht Meßpunkte in der Speicherstufe 13 abgelegt werden, wobei jeweils ein Meßpunkt nach jeder Drehung des Fahrzeugs 18 um 45º abgespeichert wird. Wie Figur 2 zeigt, stellt die so ermittelte Ortskurve 0 eine Ellipse dar, die um den konstanten Störfeldvektor Hs aus dem Achsenursprung des Vektordiagramms x, y verschoben und mit ihren Achsen um den Winkel α gedreht ist. In der Rechenstufe 15 wird nun aus den ermittelten Parametern der Ortskurve 0 der Winkel berechnet, der die Richtung des Erdfeldes He in bezug auf die x-Achse des Vektordiagramms angibt. Dieser Winkel bedarf jedoch noch einer Korrektur, da er die sogenannte Mißweisung, also die Abweichung der Erdfeldrichtung vom tatsächlichen Nordpol nicht berücksichtigt. Außerdem sind dabei nicht die Einbautoleranzen bei der Anbringung des Sensors 10 im Fahrzeug 18 berücksichtigt, so daß die x-Achse der in Fahrrichtung liegenden Sonde des Magnetometers nicht mit der Fahrzeuglängsachse Xo zusammenfällt. In Figur 3 ist diese Einbautoleranz und die Mißweisung durch ein scheinbares Vektordiagramm mit den gestrichelt dargestellten Achsen x' und y' dargestellt, welches mit den Fahrzeugachsen Xo und yo eine Drehung um den Winkel Δ bildet. Um diese Meßfehler auszugleichen, muß im Pro grammabschnitt 22 nunmehr eine Eichung des elektronischen Kompasses vorgenommen werden.T is a tensor (matrix) that contains the influence of the earth's field through shielding and magnetization of the vehicle body. He is the vector of the earth field projected onto the driving plane outside the vehicle and Hs is the vector of the constant interference field projected onto the driving plane, which is predetermined by the shape and structure of the vehicle. This vector equation is an equation with five unknowns, the vector H being known, the tensor containing three unknowns and the vector Hs also having two unknowns. In the following program section 21, all parameters for the center point shift, the shape and the rotation of the locus 0 are now calculated in the vector diagram on the computing stage i 4 of the evaluation circuit 11 with the aid of the measuring points M1 to M5. In theory, the calculation of the locus 0 would be possible from five measuring points, which can be relatively close together. In view of the inaccuracy of the measuring points, however, it is necessary that the first five measuring points in the vector diagram x, y are recorded during the rotation of the vehicle 18 by at least 90 °. However, the locus 0 can be calculated with greater accuracy if eight measuring points are stored in the storage stage 13, one measuring point being stored after each rotation of the vehicle 18 by 45 °. As FIG. 2 shows, the locus curve 0 determined in this way represents an ellipse, which is shifted by the constant interference field vector Hs from the axis origin of the vector diagram x, y and with its axes by the angle α is rotated. In the computing stage 15, the determined parameters of the locus 0 now become the angle calculated, which indicates the direction of the earth field He with respect to the x-axis of the vector diagram. However, this angle is still required a correction because it does not take into account the so-called rejection, i.e. the deviation of the direction of the earth's field from the actual north pole. In addition, the installation tolerances when mounting the sensor 10 in the vehicle 18 are not taken into account, so that the x-axis of the magnetometer probe lying in the direction of travel does not coincide with the longitudinal axis X o of the vehicle. In Figure 3, this installation tolerance and the discrepancy is shown by an apparent vector diagram with the axes x 'and y' shown in broken lines, which with the vehicle axes X o and y o a rotation by the angle Δ forms. To compensate for these measurement errors, the Pro grammage section 22 can now be carried out a calibration of the electronic compass.
Zu diesem Zweck wird das Fahrzeug auf eine vorgegebene Himmelsrichtung, im Beispielsfall nach Osten ausgerichtet. Daraus ergibt sich zur tatsächlichen Nordrichtung ein Winkel α der im Beispielsfall 90º beträgt. Diese fest vorgegebene Winkelgröße wird nun im Programmabschnitt 23 in die Korrekturstufe 16 der Auswerteschaltung 11 nach Figur 1 durch Betätigen des Tast Schalters 17 eingegeben. Zugleich wird in dieser Fahrzeugposition durch die Rechenstufe 14 und 15 aufgrund der laufenden Messungen aus der Ortskurve O die Richtung des Erdfeldes He ermittelt und der dabei auftretende Winkel α' in die Korrekturstufe 16 mit eingegeben. Dabei gibt α' wie Figur 3 zeigt - den Winkel an, den das Erdfeld He mit der scheinbaren Achse x' des Vektordiagramms x', y' bildet. Im nachfolgenden Programmschritt 24 wird nun in der Korrekturstufe 16 ein Korrekturwinkel Δ α gebildet, indem nach der GleichungFor this purpose, the vehicle is aligned in a given direction, in the example to the east. This results in an angle α to the actual north direction, which in the example is 90 °. This firmly The predetermined angular size is now entered in the program section 23 into the correction stage 16 of the evaluation circuit 11 according to FIG. 1 by pressing the switch 17. At the same time, the direction of the earth field He is determined in this vehicle position by the computing stages 14 and 15 on the basis of the ongoing measurements from the locus O and the angle α ′ that occurs is also entered in the correction stage 16. Here, as shown in FIG. 3, α 'gives the Angle at which the earth field He forms with the apparent axis x 'of the vector diagram x', y '. In the subsequent program step 24, a correction angle Δ α is now formed in the correction stage 16 by using the equation
= der durch die Fahrzeuglängsachse xo eingestellte Winkel o zur Nordrichtung von dem vom Kompaß ermittelten Winkel ' des Erdfeldes abgezogen wird. Der so gebildete Korrekturwinkel Δ wird in der Korrekturstufe 16 abgelegt und zu gleich auf die Rechenstufen 14 und 15 gegeben. Durch ihn werden Mißweisung und Einbautoleranzen kompensiert, so daß der in der Rechenstufe 15 nunmehr ermittelte Winkel α den tatsächlichen Winkel der Fahrzeuglängsachse xo zur Nordrichtung darstellt. Im nachfolgenden Programmabschnitt 25 wird nun mit Antritt einer Fahrt jeweils ein neuer Meßwert Mx auf der Ortskurve 0 in Figur 2 durch die vom Magnetometer des Sensors 10 gemessenen Werte in die Auswert eschaltung 11 eingegeben und aufgrund der ermittelten Parameter Hs, T und He wird im Programmabschnitt 26 erneut die Fahrrichtung ermittelt. Im Programmabschnitt 27 wird diese schließlich auf der Anzeige 12 ausgegeben. Im Programmabschnitt 28 wird nun durch die Auswerteschaltung 11 geprüft, ob eine Änderung der Fahrrichtung des Fahrzeugs 18 gegenüber der Richtung des zuletzt abgespeicherten Meßpunktes um einen bestimmten Winkelbetrag a auf der Ortskurve 0 im Vektordiagramm nach Figur 2 vorliegt. Ist dies nicht der Fall, so werden zyklisch die Programmabschnitte 25 bis 28 durchlaufen und jeweils die errechnete Fahrrichtung des Fahrzeugs 18 angezeigt. Beim Überschreiten eines vorgegebenen Wertes a der Fahrrichtungsänderung von beispielsweise 30 gegenüber dem zuletzt eingespeicherten Meßpunkt im Vektordiagramm nach Figur 2 wird nunmehr ein weiterer Meßpunkt im Programmschritt 20 in der Speicher stufe 13 abgespeichert und zur Überprüfung und Korrektur der ermittelten Parameter der Ortskurve 0 vom Rechner im Programmabschnitt 21 verarbeitet. Eine Eichung ist dabei nicht mehr erforderlich, da der bereitsermittelte Korrekturwinkel Δα von der Auswerteschaltung 11 nunmehr ständig berücksichtigt wird. = the angle o to the north direction set by the vehicle's longitudinal axis x o from the angle determined by the compass' the earth field is subtracted. The correction angle Δ thus formed is stored and corrected in the correction stage 16 given to computing levels 14 and 15. It compensates for the deviation and installation tolerances, so that the angle α now determined in the computing stage 15 represents the actual angle of the vehicle longitudinal axis x o to the north direction. In the subsequent program section 25, a new measured value Mx on the locus 0 in FIG. 2 is now entered into the evaluation circuit 11 by the values measured by the magnetometer of the sensor 10, and on the basis of the parameters Hs, T and He determined in the program section 26 again determined the direction of travel. In the program section 27, this is finally output on the display 12. In the program section 28, the evaluation circuit 11 now checks whether there is a change in the direction of travel of the vehicle 18 with respect to the direction of the measurement point last stored by a certain angle a on the locus 0 in the vector diagram according to FIG. If this is not the case, the program sections 25 to 28 are cyclically run through and the calculated direction of travel of the vehicle 18 is displayed in each case. When a predetermined value a of the direction of travel is exceeded, for example 30 compared to the last stored measurement point in the vector diagram according to FIG. 2, a further measurement point is now stored in program step 20 in memory stage 13 and is used to check and correct the parameters of the locus curve 0 determined by the computer in the program section 21 processed. Calibration is no longer necessary since the already determined correction angle Δα is now constantly taken into account by the evaluation circuit 11.
Will man die räumliche Lage des am Sensor 10 gemessenen Magnetfeldes H, des Erdfeldes He und des Störfeldes Hs zur Navigation ermitteln, so wird der Sensor 10 mit einem Magnetometer ausgerüstet, das gemäß Figur 5 mit drei Sonden X, Y, Z versehen ist. Von diesen Sonden liegt eine in Fahrrichtung des Fahrzeugs, eine zweite quer zur Fahrrichtung und die dritte senkrecht zur Fahrrichtung. Durch diese Sonden X, Y, Z wird die räumliche Lage, Form und Drehung der Ortskurve des am Magnetometer wirksamen Magnetfeldes H in einem räumlichen Vektordiagramm durch mindestens neun Meßpunkte gemessen und von der Auswerteschaltung zur Berechnung der erforderlichen Parameter erfaßt und abgespeichert. In diesem Fall muß auch bei der Eichung des elektronischen Kompasses das Fahrzeug nicht nur in eine vorgegebene Fahrrichtung sondern außer dem noch genau waagerecht ausgerichtet sein, damit in diesem Fall ein räumlicher Korrekturwinkel ermittelt werden kann.If you want to determine the spatial position of the magnetic field H, the earth field He and the interference field Hs measured at the sensor 10 for navigation, the sensor 10 is equipped with a magnetometer which is provided with three probes X, Y, Z according to FIG. Of these probes, one lies in the direction of travel of the vehicle, a second perpendicular to the direction of travel and the third perpendicular to the direction of travel. By means of these probes X, Y, Z, the spatial position, shape and rotation of the locus of the magnetic field H acting on the magnetometer are measured in a spatial vector diagram by at least nine measuring points and recorded and stored by the evaluation circuit for calculating the required parameters. In this case, even when calibrating the electronic compass, the vehicle must not only in a predetermined direction of travel, but also outside which are still aligned exactly horizontally so that a spatial correction angle can be determined in this case.
Die Erfindung ist nicht auf einen elektronischen Kompaß zur Bestimmung der Fahrrichtung von Kraftfahrzeugen beschränkt, da sowohl Luftfahrzeuge wie auch Wasserfahrzeuge damit ausgestattet werden können. Außerdem läßt sich der Kompaß nicht nur zur Bestimmung der Fahrrichtung verwenden sondern ganz allgemein zur Navigation von Fahrzeugen, die beispielsweise von einem fest vorgegebenen Ausgangspunkt zu einem bestimmten Zielpunkt bewegt werden sollen. In einem solchen Fall wird beispielsweise über einen Radsensor oder einen Signalgeber am Kilometerzähler des Fahrzeugs während der Fahrt ein digitales Wegsignal auf die Auswerteschaltung gegeben, der gemeinsam mit der ermittelten Fahrrichtung zur Ermittlung des jeweiligen Standortes des Fahrzeugs benutzt wird.The invention is not limited to an electronic compass for determining the direction of travel of motor vehicles, since both aircraft and watercraft can be equipped with it. In addition, the compass can not only be used to determine the direction of travel, but also very generally for navigating vehicles which, for example, are to be moved from a fixed starting point to a specific destination. In such a case, a digital path signal is given to the evaluation circuit, for example via a wheel sensor or a signal transmitter on the odometer of the vehicle, which is used together with the determined direction of travel to determine the respective location of the vehicle.
Durch die während der Fahrt laufend in die Speicherstufe 13 eingegebenen neuen Meßwerte wird eine automatische Nacheichung realisiert, durch die auch Änderungen der Form, der Lage und der Drehung der Ortskurve berücksichtigt werden. Damit ist sichergestellt, daß die Einflüsse auf das gemessene Magnetfeld H, die durch Zuschalten elektrischer Verbraucher im Kraftfahrzeug wie Scheinwerfer, Heckscheibenheizung, Scheibenwischer und dgl. oder durch Beladung des Kraftfahrzeugs hervorgerufen werden, bei der Berechnung der Fahrrichtung kompensiert werden. Mit einem Drei-Achsen-Magnetometer kann auf diese Weise auch eine räumliche Störfeldänderung in allen drei Koordinaten berücksichtigt und eine entsprechende Fehlerkompensation durchgeführt werden. Zusätzlich zur Ermittlung der Fahrzeugneigung bzw. Fahr zeugsteigung aus der Änderung der in der Fahrebene liegenden Feldvektoren kann mit einer entsprechend aufgebauten Auswerteschal tung zusammen mit Wegsignalen auch die jeweilige Standorthöhe des Fahrzeuges berechnet und ausgegeben werden. Zur Nacheichung der Höheninformation ist jedoch dann von Zeit zu Zeit ein vorgegebener Höhenstützpunkt einzugeben, The new measured values continuously entered into the storage stage 13 during the journey result in automatic re-calibration, which also takes into account changes in the shape, position and rotation of the locus. This ensures that the influences on the measured magnetic field H, which are caused by switching on electrical consumers in the motor vehicle such as headlights, rear window heating, windshield wipers and the like, or by loading the motor vehicle, are compensated for when calculating the direction of travel. In this way, a three-axis magnetometer can also take into account a spatial change in the interference field in all three coordinates and an appropriate error compensation can be carried out. In addition to the determination of the vehicle inclination or vehicle inclination from the change of the field vectors lying in the driving plane, a correspondingly constructed evaluation scarf can be used together with path signals, the respective location height of the vehicle is calculated and output. To re-calibrate the height information, a specified height base must be entered from time to time,

Claims

An sprüche Expectations
1. Verfahren zur Ermittlung der Fahrrichtung eines Fahrzeuges mit einem elektronischen Kompaß, der ein im Fahrzeug fest angeordnetes Magnetometer mit mehreren Sonden hat, die zur Messung des Magnetfeldes am Magnetometer auf senkrecht zueinander stehende Achsen liegen und mit einer Auswerteschaltung, welcher die vom gemessenen Magnetfeld abhängigen elektrischen Signale der Sonden zur Ermittlung von Richtung und Größe der am Magnetometer. wirksamen Störfelder und' des Erdfeldes sowie zur Berechnung der Fahrrichtung zugeführt werden, dadurch gekennzeichnet, daß zur Bestimmung der Ortskurve (0) des Erdfeldes (He) am Magnetometer (10) in einem durch die Sondenachsen vorgegebenen Vektordiagramm (x, y) mindestens fünf Meßpunkte (M1 ... M5 ) durch Drehen des Fahrzeuges (18) von der Auswerteschaltung (11) erfaßt und abgespeichert werden, daß ein Rechner (14) der Auswerteschaltung (11) über einen Algorithmus mit fünf Unbekannten aus den fünf MePpunkten die Parameter für die Mittelpunktsverschiebung, die Form und die Drehung der Ortskurve (0) im Vektordiagramm (x, y) errechnet, daß der Rechner (14) bei nachfolgenden Messungen (Mx) aus der Ortskurve (o) die Richtung des Erdfeldes (He) ermittelt, daß das Fahrzeug (18) auf eine vorgegebene Himmelsrichtung (Ost) ausgerichtet und der sich daraus ergebende Winkel ( αo ) zur Nordrichtung von dem vom Kompaß ermittelten Winkel ( ' ) des Erdfeldes (He) abgezogen wird und daß der so gebildete Korrekturwinkel ( Δ ) in der Auswerteschaltung (11) abgespeichert und bei den nachfolgenden Ermittlungen der Fahrrichtung aus den vom Magnetometer (10) gemessenen Werten vom Rechner (14 , 15) mit berücksichtigt wird.1. Method for determining the direction of travel of a vehicle with an electronic compass, which has a magnetometer fixedly arranged in the vehicle with several probes which lie on axes perpendicular to one another for measuring the magnetic field on the magnetometer and with an evaluation circuit which depends on the measured magnetic field electrical signals from the probes to determine the direction and size of the magnetometer. Effective interference fields and 'of the earth field and for calculating the direction of travel, characterized in that for determining the locus (0) of the earth field (He) on the magnetometer (10) in a vector diagram (x, y) predetermined by the probe axes, at least five measuring points (M1 ... M5) by rotating the vehicle (18) from the evaluation circuit (11) and storing that a computer (14) of the evaluation circuit (11) uses an algorithm with five unknowns from the five measurement points to set the parameters for the Center shift, the shape and rotation of the locus (0) in the vector diagram (x, y) calculates that the computer (14) determines the direction of the earth field (He) in subsequent measurements (Mx) from the locus (o), that the Vehicle (18) aligned to a predetermined direction (east) and the resulting angle (αo ) to North direction from the angle determined by the compass ( ') of the earth field (He) is subtracted and that the correction angle (Δ) thus formed in the evaluation circuit (11) stored and taken into account in the subsequent determinations of the direction of travel from the values measured by the magnetometer (10) by the computer (14, 15).
2. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß während der Fahrt weitere Meßpunkte (Mx) im Vektordiagramm (x, y) durch die Auswerteschaltung (11) abgespeichert und zur Überprüfung und Korrektur der ermittelten Parameter der Ortskurve (0) vom Rechner (14) verarbeitet werden.2. The method according to claim 1, characterized in that further measuring points (Mx) are stored in the vector diagram (x, y) by the evaluation circuit (11) during the journey and for checking and correcting the determined parameters of the locus curve (0) by the computer (14 ) are processed.
3. Verfahren nach Anspruch 2, dadurch gekennzeichnet, daß während der Fahrt die Änderungen der Fahrrichtung durch Messen des Magnetfeldes (H) von der Auswerteschaltung (11) erfaßt werden und daß jeweils beim Überschreiten eines vorgegebenen Wertes (a) der Fahrrichtungsänderung ein weiterer Meßpunkt (Mx) im Vektordiagramm (x, y) abgespeichert wird.3. The method according to claim 2, characterized in that the changes in the direction of travel by measuring the magnetic field (H) are detected by the evaluation circuit (11) while driving and that each time a predetermined value (a) of the change in direction a further measuring point ( Mx) is saved in the vector diagram (x, y).
4 . Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß die ersten fünf Meßpunkte (M1 ... M5 ) im Vektordiagramm (x, y) während der Drehung des Fahrzeuges (18) um mindestens 90o erfaßt und abgespeichert werden.4th A method according to claim 1, characterized in that the first five measurement points (M1 ... M5) are o detected in the vector diagram (x, y) during the rotation of the vehicle (18) by at least 90 and stored.
5. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß das Magnetometer (10) mit zwei Sonden versehen ist, deren eine Sondenachse (x) in Fahrrichtung und deren andere Sondenachse (y) quer zur Fahrrichtung in eine waagerechte Fahrzeugebene gelegt wird.5. The method according to claim 1, characterized in that the magnetometer (10) is provided with two probes, one probe axis (x) in the direction of travel and the other probe axis (y) is placed transversely to the direction of travel in a horizontal vehicle plane.
6. Verfahren nach Anspruch 5, dadurch gekennzeichnet, daß aus den Meßpunkten (M1 ... Mx ) der Ortskurve (O) im Vektordiagramm (x, y) vom Rechner (14) die Parameter einer Ellipse ermitteln werden, deren Achsen zu den Koordinaten des Vektordiagramms (x, y) gedreht sind und die mit dem Vektor (Hs) des festen Stδrfeldes aus dem Koordinatenursprung des Vektordiagramms (x, y) verschoben ist.6. The method according to claim 5, characterized in that from the measuring points (M1 ... Mx) of the locus (O) in the vector diagram (x, y) the computer (14) determine the parameters of an ellipse, its axes are rotated to the coordinates of the vector diagram (x, y) and which is shifted with the vector (Hs) of the fixed interference field from the coordinate origin of the vector diagram (x, y).
7. Verfahren nac-h Anspruch 1, dadurch gekennzeichnet, daß das Magnetometer mit drei Sonden (X, Y, Z) versehen ist, von denen eine in Fahrrichtung, eine zweite quer zur Fahrrichtung und eine dritte senkrecht zur Fahrrichtung gelegt wird.7. The method nac-h claim 1, characterized in that the magnetometer is provided with three probes (X, Y, Z), one of which is placed in the direction of travel, a second transverse to the direction of travel and a third perpendicular to the direction of travel.
8. Verfahren nach Anspruch 7, dadurch gekennzeichnet, daß von den Sonden (X, Y, Z) die räumliche Lage, Form und Drehung der Ortskurve des am Magnetometer wirksamen Magnetfeldes (H) im räumlichen Vektordiagramm durch mindestens neun Meßpunkte gemessen und von der Auswerteschaltung (11) erfaßt und abgespeichert werden. 8. The method according to claim 7, characterized in that of the probes (X, Y, Z) the spatial position, shape and rotation of the locus of the magnetic field effective on the magnetometer (H) measured in the spatial vector diagram by at least nine measuring points and by the evaluation circuit (11) can be recorded and saved.
EP85901973A 1984-06-16 1985-04-17 Process for determining the direction of travel of a vehicle, using an electronic compass Expired EP0186666B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT85901973T ATE40746T1 (en) 1984-06-16 1985-04-17 METHOD OF DETERMINING THE DIRECTION OF A VEHICLE WITH ELECTRONIC COMPASS.

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DE19843422491 DE3422491A1 (en) 1984-06-16 1984-06-16 METHOD FOR DETERMINING THE DIRECTION OF A VEHICLE WITH AN ELECTRONIC COMPASS
DE3422491 1984-06-16

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EP0186666A1 EP0186666A1 (en) 1986-07-09
EP0186666B1 true EP0186666B1 (en) 1989-02-08

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US (1) US4729172A (en)
EP (1) EP0186666B1 (en)
JP (1) JPS61502413A (en)
DE (2) DE3422491A1 (en)
WO (1) WO1986000128A1 (en)

Families Citing this family (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3509548A1 (en) * 1985-03-16 1986-09-18 Robert Bosch Gmbh, 7000 Stuttgart METHOD FOR DETERMINING THE DIRECTION OF A VEHICLE WITH AN ELECTRONIC COMPASS
JPS6394108A (en) * 1986-10-08 1988-04-25 Mitsubishi Electric Corp Azimuth detector for moving body
JPH0629732B2 (en) * 1986-10-08 1994-04-20 三菱電機株式会社 Direction detector for mobile
US4862398A (en) * 1986-11-18 1989-08-29 Sumitomo Electric Industries, Ltd. Correcting method and correcting errors in a terrestrial magnetism heading sensor
DE3644681A1 (en) * 1986-12-30 1988-07-14 Bosch Gmbh Robert NAVIGATION METHOD FOR VEHICLES WITH ELECTRONIC COMPASS
GB2213937B (en) * 1987-12-17 1992-01-22 Plessey Co Plc Navigation compass calibration
US4972593A (en) * 1989-01-17 1990-11-27 The Charles Stark Draper Laboratory, Inc. Method and apparatus for measuring the undistorted magnetic field of the earth
JPH051914A (en) * 1991-06-25 1993-01-08 Pioneer Electron Corp Compensating magnetized vector
US5724074A (en) * 1995-02-06 1998-03-03 Microsoft Corporation Method and system for graphically programming mobile toys
US5737226A (en) * 1995-06-05 1998-04-07 Prince Corporation Vehicle compass system with automatic calibration
US5878370A (en) * 1995-12-01 1999-03-02 Prince Corporation Vehicle compass system with variable resolution
RU2098764C1 (en) * 1996-05-29 1997-12-10 Русланов Александр Семенович Method for determination of moving object location and device for its realization
US6301794B1 (en) * 1999-05-27 2001-10-16 Johnson Controls, Inc. Vehicle compass system with continuous automatic calibration
US20040215387A1 (en) 2002-02-14 2004-10-28 Matsushita Electric Industrial Co., Ltd. Method for transmitting location information on a digital map, apparatus for implementing the method, and traffic information provision/reception system
JP3481168B2 (en) 1999-08-27 2003-12-22 松下電器産業株式会社 Digital map location information transmission method
JP5041638B2 (en) 2000-12-08 2012-10-03 パナソニック株式会社 Method for transmitting location information of digital map and device used therefor
JP4663136B2 (en) 2001-01-29 2011-03-30 パナソニック株式会社 Method and apparatus for transmitting location information of digital map
JP4749594B2 (en) * 2001-04-27 2011-08-17 パナソニック株式会社 Digital map location information transmission method
JP4230132B2 (en) 2001-05-01 2009-02-25 パナソニック株式会社 Digital map shape vector encoding method, position information transmission method, and apparatus for implementing the same
EP1558895B1 (en) * 2002-11-05 2008-05-21 Nokia Corporation Mobile electronic three-dimensional compass
US9046365B2 (en) * 2011-10-27 2015-06-02 Apple Inc. Electronic devices with magnetic field compensating conductive traces
KR20220127023A (en) * 2021-03-10 2022-09-19 삼성전자주식회사 Electronic device and operation method of electronic device for determining direction of movement of electronic device

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3991361A (en) * 1975-03-27 1976-11-09 Westinghouse Electric Corporation Semi-automatic compass calibrator apparatus for a vehicle mounted flux gate compass system to cancel out effect of local magnetic disturbances
US4031630A (en) * 1976-06-17 1977-06-28 The Laitram Corporation Calibration apparatus for automatic magnetic compass correction
US4091543A (en) * 1976-06-17 1978-05-30 The Laitram Corporation Automatic magnetic compass correction
DE2754888C2 (en) * 1977-12-09 1983-12-29 Günter Dipl.-Phys. 3303 Vechelde Kramer Navigation apparatus
FR2484079A1 (en) * 1980-06-05 1981-12-11 Crouzet Sa METHOD FOR COMPENSATING MAGNETIC DISTURBANCES IN THE DETERMINATION OF A MAGNETIC CAP, AND DEVICE FOR IMPLEMENTING SAID METHOD
DE3123180A1 (en) * 1981-06-11 1983-01-05 Siemens AG, 1000 Berlin und 8000 München CORRECTION METHOD AND DEVICE FOR A MAGNETIC PROBE
JPS6051114B2 (en) * 1981-07-07 1985-11-12 株式会社デンソー In-vehicle navigator
JPS5834314A (en) * 1981-08-24 1983-02-28 Nippon Soken Inc Bearing detector
JPS58135412A (en) * 1982-02-04 1983-08-12 Nippon Denso Co Ltd Direction arithmetic device
JPS58139010A (en) * 1982-02-15 1983-08-18 Nissan Motor Co Ltd Running guidance device for vehicle
JPS59155714A (en) * 1982-10-12 1984-09-04 ロケ　マナ　リサーチ　リミテッド Electronic compass for transportation facility

Also Published As

Publication number Publication date
DE3568219D1 (en) 1989-03-16
EP0186666A1 (en) 1986-07-09
WO1986000128A1 (en) 1986-01-03
DE3422491A1 (en) 1985-12-19
US4729172A (en) 1988-03-08
JPS61502413A (en) 1986-10-23

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