JPS61269015A - Vehicle advance bearing measurement - Google Patents

Vehicle advance bearing measurement

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Publication number
JPS61269015A
JPS61269015A JP11174085A JP11174085A JPS61269015A JP S61269015 A JPS61269015 A JP S61269015A JP 11174085 A JP11174085 A JP 11174085A JP 11174085 A JP11174085 A JP 11174085A JP S61269015 A JPS61269015 A JP S61269015A
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JP
Japan
Prior art keywords
vehicle
magnetization
sensor
geomagnetic
time
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.)
Granted
Application number
JP11174085A
Other languages
Japanese (ja)
Other versions
JPH0643896B2 (en
Inventor
Osamu Shimizu
修 清水
Kenji Amame
健二 天目
Kunihiko Mitsufuji
三藤 邦彦
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Sumitomo Electric Industries Ltd
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Sumitomo Electric Industries Ltd
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Filing date
Publication date
Application filed by Sumitomo Electric Industries Ltd filed Critical Sumitomo Electric Industries Ltd
Priority to JP11174085A priority Critical patent/JPH0643896B2/en
Publication of JPS61269015A publication Critical patent/JPS61269015A/en
Publication of JPH0643896B2 publication Critical patent/JPH0643896B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Abstract

PURPOSE:To obtain correct vehicle bearing information, by a method wherein geomagnetic bearing sensors different in the effect of magnetization on a vehicle to determine the angle of deflection of detection information due to magnetization from the output difference while the amount thereof is determined from the output after a time DELTAt to correct the output of the sensor. CONSTITUTION:A sensor 13 is located in ferromagnetic field MG1 by magnetization of a body 11a while a sensor 12 in a magnetic field MG2 by a weak magnetization. When the angle alpha of deflection of the bearing due to magnetization, the amount G of the deflection, the output coil constant K of the sensor and the horizontal component B of terrestial magnetism are given, the direction alphaof magnetization can be found from the outputs VX1, VY1, VX2 and VY2 of the sensors. The bearing theta(t) of a vehicle from Vx and Vy at the time (t) and moreover, a coefficient (a) indicating the density of terrestial magnetism are used to calculate VX(t+DELTA+t)VY(t+DELTAt), from which the level G of magnetization can be calculated. The outputs of the terrestial magnetism sensor are corrected by alpha and G and the effect of magnetization over the vehicle is removed to obtain a correct vehicle bearing data.

Description

【発明の詳細な説明】 〔1〕産業上の利用分野 本発明は地磁気方位センサにζよる車輌進行方位計測方
法に関する。本発明によれば車輌自身の着   □磁に
よるセンサの方位計測誤差を算出し、検出データを補正
して正確な方位を知ることができるため、貨物輸送、救
急あるいは保守などの目的で急行する車輌や一般乗用車
の運・行を効率良く行なうことができる。
DETAILED DESCRIPTION OF THE INVENTION [1] Industrial Application Field The present invention relates to a method for measuring a vehicle traveling direction using a geomagnetic direction sensor ζ. According to the present invention, it is possible to calculate the azimuth measurement error of the vehicle's own magnetic sensor and correct the detected data to determine the accurate azimuth, so that it can be used for vehicles rushing for cargo transportation, emergency services, maintenance, etc. This allows for efficient operation of passenger cars and general passenger cars.

〔2]従来技術 車載地磁気方位センサーは車両に備えられ、地磁気を検
出する事によって車両等の進行方向を計測する方位計等
のセンサとして利用されるものであって、トロイダルコ
ア型の磁界フラックスゲート式のもθ)が知られている
[2] Conventional technology Vehicle-mounted geomagnetic direction sensors are installed in vehicles and used as sensors such as direction meters that measure the direction of travel of vehicles by detecting geomagnetism. The equation θ) is also known.

ところで従来自動車等の車両は踏切を横断すると送電線
の発生する磁界によって車体フロア等が磁化される特性
を有し、これを一般に踏切着磁という。
By the way, conventional vehicles such as automobiles have a characteristic that when they cross a railroad crossing, the vehicle floor etc. are magnetized by the magnetic field generated by the power transmission line, and this is generally referred to as railroad crossing magnetization.

従って地磁気センサーを車体に配設する場合には地磁気
センサーが地磁気のみに対し感応し、上記踏切着磁の如
き車体着磁に影響されないようにする事を考慮しなけれ
ばならない。
Therefore, when arranging a geomagnetic sensor on a vehicle body, consideration must be given to ensuring that the geomagnetic sensor is sensitive only to the geomagnetism and is not affected by vehicle body magnetization such as the above-mentioned railroad crossing magnetization.

従来の上記車体着磁の影響を排除する方法とじては、例
えば特開昭59−228110号公報、特開昭60−4
806  号公報に記載されているように着磁された車
台を一つの磁石とみなし、車体上部に互に近接して配設
された少なくとも2個の地磁気センサーの出力差によっ
てその着磁量を推定し、補正する方法が提案されていた
。すなわち第2図に示すように車体着磁を車輌(ロ)の
車台(21a)に発生した仮想的な磁石(イ)として考
えれば所定の支持構造によって配設された地磁気センサ
ー翰、(ハ)の夫々の位置における磁界に係るベクトル
G 、 G’の大きさが異なる。従って地磁気センサG
 、 G’の差異に基づいて車体着磁、すなわち磁石(
イ)の磁気量を推定し、所定の地磁気センサーの出力を
補正する事によって地磁気のみによって生ずる本来の検
出信号出力を得ようとするものである。
Conventional methods for eliminating the influence of vehicle body magnetization are disclosed, for example, in Japanese Patent Application Laid-Open No. 59-228110 and Japanese Patent Application Laid-open No. 60-4.
As described in Publication No. 806, the magnetized vehicle chassis is regarded as one magnet, and the amount of magnetization is estimated based on the output difference of at least two geomagnetic sensors placed close to each other on the upper part of the vehicle body. A method for correcting this has been proposed. In other words, as shown in Fig. 2, if we consider the vehicle body magnetization as a virtual magnet (A) generated on the chassis (21a) of the vehicle (B), the geomagnetic sensor wire (C) is arranged by a predetermined support structure. The magnitudes of the vectors G and G' related to the magnetic field at each position are different. Therefore, geomagnetic sensor G
, based on the difference in G', the car body is magnetized, that is, the magnet (
(b) By estimating the amount of magnetism and correcting the output of a predetermined geomagnetic sensor, it attempts to obtain the original detection signal output generated only by geomagnetism.

〔3〕従来技術の問題点 斯かる従来の方法によれば地磁気の大きさを仮定して計
算を進めなければならず、測定地点による地磁気の大き
さの変動がそのまま方位測定誤差の原因になるという重
大な欠点が存した。本発明者は上記問題に鑑み、これを
有効に解決すべく本発明を成したものである。
[3] Problems with the conventional technology According to this conventional method, calculations must be performed assuming the magnitude of the earth's magnetism, and variations in the magnitude of the earth's magnetism depending on the measurement point directly cause errors in azimuth measurement. There was a serious drawback. In view of the above-mentioned problem, the present inventor has created the present invention in order to effectively solve the problem.

(栢問題点を解決するための手段 ? 本発明の目的は車両の方位計等に使用される車載地磁気
センサの検出出力に有効に補正を施して車体α0、(l
la)への着磁の影響を排除し、本来の地磁気による出
力のみを検出し得るようにする事にあり、その特徴は通
常の地磁気センサー1’141とは別の地磁気センサ(
2)を車体着磁の影響MCI、MG2の強い方の磁場M
Glの中にある箇所に配設し、まず時刻tにおいて両地
磁気センサーの出力の差異に基づいて車体の着磁の方向
を計算し、次、に一定時間後(Δt)における両地磁気
センサーの出力と時刻tにおける両地磁気センサーの出
力とから車体着磁の大きさを計算し、以上の結果より、
上記通常の地磁気センサーの検出出力を補正し、本来の
方位を検出するようにした事にある。
(Means for solving the problem? The purpose of the present invention is to effectively correct the detection output of an on-vehicle geomagnetic sensor used for a vehicle compass, etc., so that the vehicle body α0, (l
The purpose is to eliminate the influence of magnetization on la) and to be able to detect only the output due to the original geomagnetism, and its feature is that it is a geomagnetic sensor (
2) The influence of vehicle body magnetization MCI, the stronger magnetic field M of MG2
First, the direction of magnetization of the vehicle body is calculated based on the difference in the output of both geomagnetic sensors at time t, and then the output of both geomagnetic sensors after a certain period of time (Δt) is calculated. The magnitude of the vehicle body magnetization is calculated from the outputs of both geomagnetic sensors at time t, and from the above results,
The detection output of the above-mentioned normal geomagnetic sensor is corrected to detect the original direction.

以下に第1図を用いて詳述する。This will be explained in detail below using FIG.

第1のセンサα3はルーフから直下I!l  の所にと
りつけられ、車台(lla)の着磁により強い磁場Gの
中にある。第2のセンサα4はルーフから77g  の
位置にあってlsはI!lよりも大きいものとすると、
MCIよりも弱い着磁による磁界MGg Kある。
The first sensor α3 is directly below the roof I! It is attached at a location 1 and is in a strong magnetic field G due to the magnetization of the chassis (lla). The second sensor α4 is located 77g from the roof and ls is I! If it is larger than l,
There is a magnetic field MGg K due to magnetization that is weaker than MCI.

第3図にフラックスゲート型地磁気方位センサ、第4図
J/?:、車体着磁による方位誤差の状態を説明する。
Fig. 3 shows a fluxgate type geomagnetic direction sensor, Fig. 4 J/? : Explains the state of orientation error due to vehicle body magnetization.

第3図においてトロイダルコア(3υには励磁回路(支
)があって、互いに直交する出力巻線(至)と(至)か
らはそれぞれ出力Vxとvyとがとり出される。次に第
4図の実線で示されている円(42は地磁気以外の磁界
が重畳された状態で車輌が860度回転した時の検出出
力を示していて、点線(41)で示す真の方位に対応す
る出力+311とはその中心がα、そして偏位量Gだけ
方位誤差が生じている。換言すると、車輌がB点I/ζ
向いているものとして方位角はθ′と検出しているが真
の方位角はθで、実際の方位はA点にあって、角度φが
方位誤差となる。
In Fig. 3, there is an excitation circuit (support) in the toroidal core (3υ), and outputs Vx and vy are taken out from the output windings (to) and (to), which are orthogonal to each other, respectively.Next, in Fig. 4 The circle shown by the solid line (42 indicates the detection output when the vehicle rotates 860 degrees with a magnetic field other than the earth's magnetism superimposed, and the output corresponding to the true direction shown by the dotted line (41) +311 The center is α, and a direction error occurs by the deviation amount G.In other words, the vehicle is at point B I/ζ
Although the azimuth is detected as θ', the true azimuth is θ, the actual azimuth is at point A, and the angle φ is the azimuth error.

第1のセンサの互いに直交する出力巻線から取り出され
た出力をVXI、 VYI、第2のセンサの出力をVX
2. Vyg  とすると、それらの出力ベクトルは次
式で表わされる。
The output taken from the mutually orthogonal output windings of the first sensor is VXI, VYI, and the output of the second sensor is VX.
2. Vyg, their output vectors are expressed by the following equation.

こ−にθは車輌回転角、αは車輌着磁による方位の偏位
角、 Gl、 Gz  はそれぞれ第1と第2のセンサ
における着磁界による方位偏位量、Kはセンサ出力コイ
ル定数、Bは地磁気の水平成分である。
Here, θ is the vehicle rotation angle, α is the deviation angle of the azimuth due to vehicle magnetization, Gl and Gz are the amount of azimuth deviation due to the magnetizing field in the first and second sensors, respectively, K is the sensor output coil constant, and B is the horizontal component of the geomagnetic field.

上の式から式(5) 、(6)が得られる。Equations (5) and (6) are obtained from the above equations.

Vx−Vx’=(Gl−Gg)cosα−−−−−−−
−(5)Vy−Vy’=(Gt−G2)sina  −
−−−−−−−(6)従って、 第(7)式のαは車体着磁の方向を表わしている。
Vx-Vx'=(Gl-Gg)cosα----
-(5)Vy-Vy'=(Gt-G2)sina-
------- (6) Therefore, α in equation (7) represents the direction of vehicle body magnetization.

以上で着磁の方向がわかったので、次をて着磁の)  
 大きさを計算により求める。
Now that we know the direction of magnetization, let's do the following:
Find the size by calculation.

列、i いまある時刻(1)におけるセンサー出力をVx (t
)e Vy(t)、また時刻(t+Δt〕におけるセン
サー出力を■(t+Δt) s Vy (t+Δt) 
とおくと、次の関係式が得られる。
Column, i The sensor output at the current time (1) is Vx (t
)e Vy(t), and the sensor output at time (t+Δt) is (t+Δt) s Vy (t+Δt)
Then, the following relational expression is obtained.

Vx(t) = KBcosθ(t)+ Gcosa 
 +++   −一α0Vy(t) = KBsinθ
(t)+G51nα−++  −一α9Vx (t+Δ
t)=aKBcos (θ(t)+Δθ)+Gcosα
−饅Vy (t+Δt)=aKBsin (θ(t)+
Δθ)+G51nα−(至)Δθ: 時刻(1)から時
刻(む+Δt)の間に変化した車の方位角度 a:地磁気の濃淡を表わす係数で以下の式で求められる
Vx(t) = KBcosθ(t)+Gcosa
+++ −−α0Vy(t) = KBsinθ
(t)+G51nα−++ −−α9Vx (t+Δ
t)=aKBcos (θ(t)+Δθ)+Gcosα
−Ran Vy (t+Δt)=aKBsin (θ(t)+
Δθ)+G51nα−(to)Δθ: Azimuth angle a of the vehicle that changed between time (1) and time (m+Δt): A coefficient representing the intensity of the geomagnetic field and is determined by the following formula.

こ〜にJ、I、及びKは下記の式から求められる値であ
る。
Here, J, I, and K are values obtained from the following formula.

J=−Vx(t+Δt)sin(α+Δθ)+Vy(t
) cos (α−Δθ〕       (至)I =
 Vx(t)sina−Vy(t)cosα     
    αQK=Vx(t+Δt)sina−vy(t
+Δt)cosα αηまた着磁の大きさGは asinαsi+lt+cosα−a cosαcos
i/1Vy(t+Δt)  aVy(t)cosΔθ−
aVx(t)sinΔθsinα−asinαCOSΔ
θ−acosαsinΔθ1j となる。
J=-Vx(t+Δt) sin(α+Δθ)+Vy(t
) cos (α−Δθ] (to) I =
Vx(t)sina-Vy(t)cosα
αQK=Vx(t+Δt)sina-vy(t
+Δt) cosα αη Also, the magnitude of magnetization G is asinαsi+lt+cosα−a cosαcos
i/1Vy(t+Δt) aVy(t) cosΔθ−
aVx(t) sinΔθsinα−asinαCOSΔ
θ−acosαsinΔθ1j.

以上よりG、とαがbとまったので、 時刻tにおける車の方位θ(1)は、 時刻(t+Δt)における車の方位θ(t+Δt)は、
となる。
From the above, since G and α have stopped at b, the car's heading θ(1) at time t is, The car's heading θ(t+Δt) at time (t+Δt) is
becomes.

〔6〕実施例 本発明の実施例を以下に記載する。又第5図、第6図及
び第7図はそれぞれ実施例に対応する。
[6] Examples Examples of the present invention are described below. Moreover, FIGS. 5, 6, and 7 each correspond to an embodiment.

暑 目 【7]発明の効果 本発明では車体着磁の影響の異なる複数の位置に複数の
地磁気方位センサを配置し、それぞれの出力差から着磁
に起因する検出データの偏位角α(着磁の方向)を求め
、さらにある時刻(1)とそれ   □から(Δt)の
時間を経過した時刻におけるセンサ出力とから、偏位量
(着磁の大きさ)Gを算出し、αとGを用いて地磁気セ
ンサの出力を補正するので、車体着磁の影響を除去した
正確な車輌方位データが得られる。
Hot Eyes [7] Effects of the Invention In the present invention, a plurality of geomagnetic azimuth sensors are arranged at a plurality of positions where the influence of vehicle body magnetization is different, and the deviation angle α of detection data caused by magnetization is calculated from the output difference between each sensor. Then, from a certain time (1) and the sensor output at a time when (Δt) has elapsed from □, the deviation amount (magnetization magnitude) G is calculated, and α and G Since the output of the geomagnetic sensor is corrected using

【図面の簡単な説明】[Brief explanation of the drawing]

第1図は本発明の計測方法を実施するための構成を示す
図である。 第2図は従来の計測方法を説明する図である。 第3図はフラックスゲート型地磁気センサの構成を示す
図である。 第4図は車体着磁による方位誤差の状態を示すための図
である。 11:車輌 11a:車台 12:繕φ 18:第1のセンサ 14=第2のセンサ 21:車輌 21a:車台 22:磁石 28.24:地磁気センサ 31ニドロイダルコア 32:耐磁巻線 33.84:出力コイル
FIG. 1 is a diagram showing a configuration for implementing the measurement method of the present invention. FIG. 2 is a diagram illustrating a conventional measurement method. FIG. 3 is a diagram showing the configuration of a fluxgate type geomagnetic sensor. FIG. 4 is a diagram showing the state of orientation error due to vehicle body magnetization. 11: Vehicle 11a: Chassis 12: Repair φ 18: First sensor 14 = Second sensor 21: Vehicle 21a: Chassis 22: Magnet 28. 24: Geomagnetic sensor 31 Nidroidal core 32: Anti-magnetic winding 33. 84: Output coil

Claims (3)

【特許請求の範囲】[Claims] (1)地磁気方位センサにより車輌の進行方位計測を行
なう方法であつて、車輌の車体着磁による磁界の強さの
異なる複数の位置にそれぞれ地磁気方位センサを配置し
、これら複数のセンサの地磁気ならびに車体着磁により
誘起される出力を時刻(t)と時刻(t+Δt)のそれ
ぞれの時刻において計測して車体着磁による偏位角αと
偏位量Gとを算出し、両者に基づいて、時刻(t)にお
ける車輌回転角θ(t)を次式により求め車輌の進行方
位とすることを特徴とする車輌進行方位計測方法。 θ(t)=tan^−^1(Vy(t)−GSinα)
/(Vx(t)−GCosα)こゝにVx,Vyは車体
着磁による磁界の強い位置に配置された地磁気センサの
出力である。
(1) A method of measuring the traveling direction of a vehicle using a geomagnetic azimuth sensor, in which the geomagnetic azimuth sensor is placed at a plurality of positions where the strength of the magnetic field due to the body magnetization of the vehicle differs, and the geomagnetic direction of these multiple sensors is measured. The output induced by the vehicle body magnetization is measured at time (t) and time (t+Δt), the deviation angle α and the deviation amount G due to the vehicle body magnetization are calculated, and based on both, the time A method for measuring a vehicle traveling direction, characterized in that the vehicle rotation angle θ(t) at (t) is determined by the following equation and taken as the vehicle traveling direction. θ(t)=tan^-^1(Vy(t)-GSinα)
/(Vx(t)-GCosα) Here, Vx and Vy are the outputs of a geomagnetic sensor placed at a position where the magnetic field due to vehicle body magnetization is strong.
(2)車輌に配置された地磁気センサが、車体着磁の影
響の強い位置に配置された第1のセンサと、車体着磁の
影響の弱い位置に配置された第2のセンサとからなり、
第1のセンサの出力Vx_1,Vy_1,および第2の
センサの出力Vx_2,Vy_2とを、時刻(t)およ
び(t+Δt)において測定し、その値から次式により
、車体着磁による偏位角(α)と偏位量(G)を算出す
ることを特徴とする特許請求の範囲第1項記載の車輌進
行方位計測方法。 α=tan^−^1(Vy_1−Vy_2)/(Vx_
1−Vx_2)G=(Vx_1(t+Δt)−aVx1
(t)cosΔθ+aVy1(t)sinΔθ)/(a
sinαsinΔθ+cosα−acosαcosΔθ
)こゝにaは地磁気の濃淡を表わす係数、 Δθは時間Δtの間の車輌回転角の変化量
(2) The geomagnetic sensor placed on the vehicle consists of a first sensor placed at a position where the influence of car body magnetization is strong and a second sensor placed at a position where the influence of car body magnetization is weak;
The outputs Vx_1, Vy_1 of the first sensor and the outputs Vx_2, Vy_2 of the second sensor are measured at time (t) and (t+Δt), and from the values, the deviation angle due to vehicle body magnetization ( The vehicle traveling direction measuring method according to claim 1, characterized in that the vehicle traveling direction measuring method comprises calculating the amount of deviation (G) and the amount of deviation (G). α=tan^-^1(Vy_1-Vy_2)/(Vx_
1-Vx_2)G=(Vx_1(t+Δt)-aVx1
(t)cosΔθ+aVy1(t)sinΔθ)/(a
sinαsinΔθ+cosα−acosαcosΔθ
) Here, a is a coefficient representing the intensity of geomagnetism, and Δθ is the amount of change in the vehicle rotation angle during time Δt.
(3)車輌回転角(θ)が車輪速を計測することによつ
て検出されることを特徴とする特許請求の範囲第1項及
び第2項記載の車輌進行方位計測方法。
(3) A vehicle traveling direction measuring method according to claims 1 and 2, characterized in that the vehicle rotation angle (θ) is detected by measuring wheel speed.
JP11174085A 1985-05-23 1985-05-23 Vehicle heading measurement method Expired - Lifetime JPH0643896B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP11174085A JPH0643896B2 (en) 1985-05-23 1985-05-23 Vehicle heading measurement method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP11174085A JPH0643896B2 (en) 1985-05-23 1985-05-23 Vehicle heading measurement method

Publications (2)

Publication Number Publication Date
JPS61269015A true JPS61269015A (en) 1986-11-28
JPH0643896B2 JPH0643896B2 (en) 1994-06-08

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Country Status (1)

Country Link
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63196811A (en) * 1987-02-10 1988-08-15 Sumitomo Electric Ind Ltd Magnetization correction method of earth magnetism azimuth sensor
JPS63214614A (en) * 1987-03-03 1988-09-07 Sumitomo Electric Ind Ltd Method for measuring traveling azimuth of vehicle

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63196811A (en) * 1987-02-10 1988-08-15 Sumitomo Electric Ind Ltd Magnetization correction method of earth magnetism azimuth sensor
JPS63214614A (en) * 1987-03-03 1988-09-07 Sumitomo Electric Ind Ltd Method for measuring traveling azimuth of vehicle

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