JPS61147104A - Azimuth detecting device for vehicle - Google Patents

Azimuth detecting device for vehicle

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Publication number
JPS61147104A
JPS61147104A JP26934584A JP26934584A JPS61147104A JP S61147104 A JPS61147104 A JP S61147104A JP 26934584 A JP26934584 A JP 26934584A JP 26934584 A JP26934584 A JP 26934584A JP S61147104 A JPS61147104 A JP S61147104A
Authority
JP
Japan
Prior art keywords
azimuth
value
timing
azimuth vector
vector
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.)
Pending
Application number
JP26934584A
Other languages
Japanese (ja)
Inventor
Hiroo Shimizu
清水 啓夫
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.)
Niles Parts Co Ltd
Original Assignee
Niles Parts Co Ltd
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 Niles Parts Co Ltd filed Critical Niles Parts Co Ltd
Priority to JP26934584A priority Critical patent/JPS61147104A/en
Publication of JPS61147104A publication Critical patent/JPS61147104A/en
Pending legal-status Critical Current

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Abstract

PURPOSE:To correct the azimuth detection error of a vehicle automatically by calculating an azimuth vector indicating the magnetic north at specific intervals of timing on the basis of the output signal of a magnetism sensing element which detects the earth magnetism. CONSTITUTION:A microcomputer 1 reads data from the magnetism sensing element 2 and it is judged at intervals of timing on the basis of the data from the element 2 and reference decision values VX0 and VY0 whether the azimuth vector C or C' indicating the magnetic north is collected over a 360 deg. direction range or not. Then, the mean value Re' of the value of the azimuth vector C' at current timing is calculated and it is decided whether the current mean value exceeds the mean value Re of the value of the azimuth vector C at the last timing by a specific quantity or not. When it is decided whether an YES decision is continued in a specific-distance run or not to prevent an error in detection due to a transient disturbance noise, etc. Then, the X-directional component dx and Y-directional component dy of the mean value Re' are added to reference values VX0 and VY0 at the last timing to vary each reference decision value. Then, a circle test is taken and an error in reference decision value is adjusted finely on the basis of the test result.

Description

【発明の詳細な説明】 〔産業上の利用分野〕 本発明は車両用方位検出装置に関し、特に車体の着磁等
による方位の検出誤差を自動的に補正する装置に関する
DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a vehicle azimuth detection device, and more particularly to a device that automatically corrects azimuth detection errors caused by magnetization of a vehicle body, etc.

〔従来の技術〕[Conventional technology]

従来、この種の技術としては例えば、特開昭58−13
5911号公報に示されるものがあった。
Conventionally, as this type of technology, for example, Japanese Patent Application Laid-Open No. 58-13
There was one shown in Publication No. 5911.

これは、庫両用ナビゲーションシステムのCR7画面に
車両の無着磁状態における方位センサの全方位検出基漁
パターンを表示する一方、車両を周回運転した時に方位
センサが実際に出力する全方位検出パターンを087画
面上に表示し、前記基漁パターンとの位置ずれを乗員が
確認し調整ボリュームを操作することにより車体の着磁
等による方位の検出誤差を補正するもの1嘩 森 I)
−一 〔本発明が解決しようとする問題点〕 かかる従来の技術によれば、手動により誤差を補正しな
ければいけない為、車両走行中に常時誤差を補正するこ
とは実際上困難であった。
This displays the omnidirectional detection pattern of the orientation sensor when the vehicle is in a non-magnetized state on the CR7 screen of the dual-use navigation system, while also displaying the omnidirectional detection pattern that the orientation sensor actually outputs when the vehicle is driven around the vehicle. 087 Displayed on the screen, the crew member confirms the positional deviation from the basic fishing pattern and operates the adjustment volume to correct the error in detecting the direction due to the magnetization of the car body, etc. 1)
-1 [Problems to be Solved by the Present Invention] According to such conventional technology, since errors must be corrected manually, it is actually difficult to constantly correct errors while the vehicle is running.

一方、車両走行中に於いては、直流変電所や他車両等の
近接に伴なう自走車両の車体の着磁状態の変化が頻繁に
発生するが、車両用ナビゲーションシステムごとき方位
センサの検出する方位に基づき道順案内等をする場合、
方位の検出誤差を常時性なわないと誤差が積重なってし
まい実用性の全くないものとなってしまう為、常時誤差
を補正する必要、があシ、その為には自動的に補正する
手段が望まれた。
On the other hand, while the vehicle is running, the magnetization state of the self-propelled vehicle's body frequently changes due to the proximity of DC substations, other vehicles, etc. When providing directions etc. based on the direction,
If the direction detection error is not constantly corrected, the error will accumulate and become completely impractical, so it is necessary to constantly correct the error, and for that purpose there is a method to automatically correct it. It was desired.

〔問題点を解決するだめの手段〕[Failure to solve the problem]

本発明はかかる欠点を解消すべく発案されたものであり
、地磁気を検出する感磁要素と、該感磁要素の出力信号
を処理する信号処理回路とでなる方位検出装置に於いて
、前記感磁要素の出力信号に基づき所定タイミング毎に
磁北を示す方位ベクトルを演算し、今回タイミングにお
ける方位ベクトルの大きさの平均値が前回タイミングに
おける方位ベクトルの大きさの平均値に対して所定量大
きくなると、前回の全方位ベクトルの中心値に今回の方
位ベクトルの平均値を加減算することにより方位ベクト
ルの中心値を変更すべく構成された中心値変更手段を具
備してなる車両用方位検出装置を提供するものである。
The present invention was devised to eliminate such drawbacks, and includes a direction detecting device comprising a magnetically sensitive element that detects earth's magnetism and a signal processing circuit that processes an output signal of the magnetically sensitive element. An azimuth vector indicating magnetic north is calculated at each predetermined timing based on the output signal of the magnetic element, and when the average value of the magnitude of the azimuth vector at the current timing is larger than the average value of the magnitude of the azimuth vector at the previous timing by a predetermined amount. , provides a vehicle azimuth detection device comprising a center value changing means configured to change the center value of the azimuth vector by adding or subtracting the average value of the current azimuth vector to the center value of the previous omnidirectional vector. It is something to do.

〔作用〕[Effect]

本発明は紙上の手段により、所定タイミング内で得られ
た方位ベクトルの大きさ成分の平均値を順時比較し、今
回の平均値が前回の平均値に対して所定量大きくなると
、前回の全方位ベクトルの力点つまり中心値に今回の方
位ベクトルの平均値を加減算することにより方位ベクト
ルの力点つ1り中心値を変更し、方位の検出誤差を自動
的に補正すべく作用する。
The present invention uses paper means to sequentially compare the average values of the magnitude components of the azimuth vectors obtained within a predetermined timing, and when the current average value is larger than the previous average value by a predetermined amount, the previous average value is By adding or subtracting the current average value of the azimuth vector to the emphasis point, that is, the center value, of the azimuth vector, the central value of the azimuth vector is changed one by one, and the error in detecting the azimuth is automatically corrected.

〔実施例〕〔Example〕

本発明の好適な実施例を添付図面に基づき詳述する。 Preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

第1図は、本発明の好適な実施例を示す電気ブロック図
であり、第1図に於いて1は中心値変更手段としてのプ
ログラムを有するマイクロコンピュータ、2は感磁要素
としての感磁素子、3は前記感磁素子2及びマイクロコ
ンピュータ1間に介設されたA−Dコンバータ、4は車
両の走行距離等を算出するだめの信号をマイクロコンピ
ュータ1に入力する車速センサ、5は地図情報等をマイ
クロコンピュータ1に読み込むだめのROMカードリー
ダー、6は道順案内のだめの出発地や到着地等を乗員が
入力するためのキーボード、7は地図情報、道順案内及
び方位等を表示するCRT若しくは液晶等によるドツト
マトリックスディスプレイからなる表示部−乃び8はマ
イクロコンピュータ1からの信号に基づき表示部7を制
御する表示部コントローラである。
FIG. 1 is an electrical block diagram showing a preferred embodiment of the present invention. In FIG. 1, 1 is a microcomputer having a program as center value changing means, and 2 is a magnetic sensing element as a magnetic sensing element. , 3 is an A-D converter interposed between the magnetic sensing element 2 and the microcomputer 1, 4 is a vehicle speed sensor that inputs a signal for calculating the distance traveled by the vehicle, etc. to the microcomputer 1, and 5 is map information. A ROM card reader is used to read information such as information into the microcomputer 1, a keyboard 6 is used by the crew to input information such as departure and arrival points for route guidance, and 7 is a CRT or liquid crystal display for displaying map information, route guidance, directions, etc. A display section 8 consisting of a dot matrix display manufactured by E.T. et al. is a display section controller that controls the display section 7 based on signals from the microcomputer 1.

以下、第2図及び第3図を用いて本発明の好適な実施例
の作用を説明する。
Hereinafter, the operation of the preferred embodiment of the present invention will be explained using FIGS. 2 and 3.

先づ第2図におしへて、aは例えば車両に加わる磁気の
横方向つまりX方向成分を検知して感磁素子2が出力す
る電気信号、bは同じく車両の進行方向つまりY方向成
分を検知して出力する電気信号である。又、Cは前記X
方向信号a及びY方向信号すの2人力によりマイクロコ
ンピュータ1で演算された磁北を示す方位ベクトルであ
り、dは前記方位ベクトルCの力点、eは方位ベクトル
Cの大きさをそれぞれ示したものである。尚、前記力点
dは便宜上前回の全方位ベクトルの中心と称する。又、
この力点dt/iX方向及びY方向に加わる地磁気が零
の状態を判定するためにマイクロコンピュータ1が有す
るX方向零状態の判定基准値Vxo及びY方向零状態の
判定基部値Vyoを合成したものであり、該判定基醜値
VXO及びVyoは後述する誤差補正の作用により書き
換えられる値である。
First, in Fig. 2, a is an electric signal output by the magneto-sensitive element 2 by detecting, for example, the lateral direction, that is, the X-direction component of the magnetism applied to the vehicle, and b is the electric signal that is output in the traveling direction of the vehicle, that is, the Y-direction component. This is an electrical signal that is detected and output. Also, C is the above-mentioned
It is an azimuth vector indicating the magnetic north calculated by the microcomputer 1 by two manual inputs of the direction signal a and the Y direction signal S, d is the power point of the azimuth vector C, and e is the magnitude of the azimuth vector C. be. Note that the power point d is referred to as the center of the previous omnidirectional vector for convenience. or,
This force point dt/i is a composite of the determination reference value Vxo for the X direction zero state and the determination base value Vyo for the Y direction zero state, which the microcomputer 1 has, in order to determine the state in which the earth's magnetism applied in the X and Y directions is zero. The criterion ugliness values VXO and Vyo are values that are rewritten by the action of error correction, which will be described later.

今ここで、前記判定基’&Vxo及びVyoが適正であ
ると、車体の着磁等による磁界の影響を見かけ上受けず
、車両を周回運転した時方位ベクトルCは全方向に大き
さθがほぼ一定の円を描くことになる。したがって、こ
の状態にお(^ては正確な磁北方向を検知することがで
きる。
Now, if the judgment criteria '&Vxo and Vyo are appropriate, there will be no apparent influence of the magnetic field due to the magnetization of the vehicle body, and when the vehicle is driven around, the azimuth vector C will have approximately the same magnitude θ in all directions. It will draw a certain circle. Therefore, in this state, it is possible to accurately detect the magnetic north direction.

所で、車両走行中に高架線等による強力な磁界の影響を
受けだとする。すると、感磁素子2が出力するX方向信
号a′及びY方向信号b′はそれぞれバイアス状態に成
ってしまい、車両を周回運転しても前回の全方位ベクト
ルの中心)   である力点dを基部としだ方位ベクト
ルC′の向きはほぼ一方向に傾向する。
Now suppose that a vehicle is affected by a strong magnetic field from an elevated wire while it is running. Then, the X-direction signal a' and the Y-direction signal b' output by the magnetic sensing element 2 become biased, and even if the vehicle is driven around, the point of force d, which is the center of the previous omnidirectional vector, is the base point. The direction of the Toshida azimuth vector C' tends to be approximately in one direction.

しかし、川口運転や通常走行により得られた多くの方位
ベクトルC′のデータを平均し算出されたベクトルの大
きさ及び向きは全方位ベクトル中心の偏心量に近似する
原理を有しており、この原理を用いて誤差補正を行なう
作用を第3図に示すフローチ・ヤードを用いて詳述する
However, the magnitude and direction of the vector calculated by averaging the data of many azimuth vectors C' obtained from Kawaguchi driving and normal driving have a principle that approximates the eccentricity of the center of all directional vectors. The operation of error correction using the principle will be explained in detail using the flow yard shown in FIG.

先づ、ステップ101では不要な蓄積データを消却し感
磁素子2からのデータを読み込みステップ102に進む
First, in step 101, unnecessary accumulated data is erased, data from the magnetic sensing element 2 is read, and the process proceeds to step 102.

ステップ102では、所定タイミング毎に前記感磁素子
2からのデータ及び判定基迩値Vxo。
In step 102, the data from the magneto-sensitive element 2 and the judgment reference value Vxo are collected at predetermined timings.

Vyoに基づき演算された磁北を示す方位ペクト、υC
若しくはC′が560度方向分収集されたかを判定し、
YESであればステップ107に進み、Noであればス
テップ105に進む。
Azimuth pect indicating magnetic north calculated based on Vyo, υC
Or determine whether C′ has been collected in 560 degrees,
If YES, proceed to step 107; if NO, proceed to step 105.

ステップ106では、今回タイミングにおける方位ベク
トルC′の大きさの平均値Rθ′を算出し、ステップ1
04に進む。
In step 106, the average value Rθ' of the magnitude of the azimuth vector C' at the current timing is calculated, and in step 1
Proceed to 04.

ステップ104では、今回、タイミングにおける前記平
均値Re′が前回タイミングにおける方位ベクトルCの
大きさの平均値R8に対して所定量例えばRe以上に成
ったかを判定し、Yllであればステップ105に進み
、NOであればステップ101に帰る。補足説明すれば
、前記前回タイミングにおける方位ベクトルCの大きさ
の平均値R,は判定基部値Vxo、 Vyoつまり全方
位ベクトルの中心である力点dが適正であれば各方位ベ
クトルCの大きさeにほぼ等しく八ことが言える。
In step 104, it is determined whether the average value Re' at this timing is greater than a predetermined amount, for example Re, with respect to the average value R8 of the magnitude of the azimuth vector C at the previous timing, and if Yll, the process proceeds to step 105. , if NO, the process returns to step 101. To give a supplementary explanation, the average value R of the magnitudes of the azimuth vectors C at the previous timing is the determination base value Vxo, Vyo, that is, the magnitude e of each azimuth vector C if the emphasis point d, which is the center of all azimuth vectors, is appropriate. Eight things can be said about the same thing.

ステップ105は、前記ステラ7’1041CおけるY
ES判定が所定距離走行中に続いたかを判定するステッ
プであり、一時的な外乱ノイズ等による誤検出を防止す
るものである。そして、判定がYESであればステップ
106に進み、NOであれば101に・帰る。
Step 105 includes Y in the Stella 7' 1041C.
This is a step of determining whether the ES determination continues while the vehicle is traveling a predetermined distance, and is intended to prevent erroneous detection due to temporary disturbance noise or the like. If the determination is YES, the process advances to step 106; if the determination is NO, the process returns to 101.

ステップ106では、前回タイミングにおける全方位ベ
クトルの中、1゛1.L−1での力点dを今回り゛イミ
ングにおける方位ベクトルC′の平均値し Re’だけ移動する処理14テツプ101に帰る。
In step 106, among the omnidirectional vectors at the previous timing, 1.1. The process 14 returns to step 101 where the power point d at L-1 is set to the average value of the azimuth vector C' at the current timing and moved by Re'.

つまり、前回タイミングにおける判定基部値Vxo、 
Vyoに前記平均値Re /のX方向成分dx及びY方
向成分ayを加算することにより各判定基部値を変更す
る。ここに於いて、上記ステップ103ないしステップ
106は中心値変更手段としてのステップである。
In other words, the determination base value Vxo at the previous timing,
Each determination base value is changed by adding the X-direction component dx and Y-direction component ay of the average value Re / to Vyo. Here, steps 103 to 106 are steps as a center value changing means.

次に、ステップ107では円検定つまり全方位ベクトル
の描く円の真円度若しくは偏心度を検定し検定結果に基
づきステップ108で各判定基臨値の誤差を微調整しス
テップ101に帰る。
Next, in step 107, a circle test is performed, that is, the circularity or eccentricity of the circle drawn by the omnidirectional vector is tested, and based on the test result, the error of each criterion value is finely adjusted in step 108, and the process returns to step 101.

尚、本発明は車両走行中や駐停車中に車両の着磁状態等
が大きく変化し、判定基部の微調整等が仮にできなくな
ってしまった時にも、今回タイミングにおける方位ベク
トルの平均値分だけ判定基部を変更することにより概ね
補正し、微調整できるレベルまで適正値に近似できるも
のであればよく、実施例に限定されるものではな(^。
Furthermore, in the present invention, even if the magnetization state of the vehicle changes significantly while the vehicle is running or parked or parked, and it becomes impossible to make fine adjustments to the determination base, it is possible to make fine adjustments to the determination base only by the average value of the azimuth vector at the current timing. It is not limited to the examples, as long as it can approximate the appropriate value to a level that can be roughly corrected and finely adjusted by changing the determination base (^.

〔本発明の効果〕[Effects of the present invention]

本発明は、上記した構成、作用により自動的に方位検出
誤差を補正することができ、車両走行中においても常時
誤差を補正されるため誤差が積重なることがなく車両用
ナビゲーションシステムに最適であり、且つ車両の着磁
状態が急に大きく変化しても第1段階として概ね誤差補
正値に近似できるため速やかな補正が可能である等の優
れた種々の効果を奏する。
INDUSTRIAL APPLICABILITY The present invention is capable of automatically correcting direction detection errors through the above-described configuration and operation, and is constantly corrected even while the vehicle is running, so errors do not accumulate, making it ideal for vehicle navigation systems. In addition, even if the magnetization state of the vehicle suddenly changes greatly, it can approximate the error correction value in the first stage, so it has various excellent effects such as being able to quickly correct the error correction value.

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

第1図は、本発明の好適な実施例を示す電気ブロック図
である。第2図は第1図に示す実施例による方位検出誤
差の補正作用を説明する作用説明図である。 第6図は第1図に示す実施例のマイクロコンピュータが
有する誤差補正のプログラムのフローチャートである。 1・・・・・・マイクロコンピュータ、2・・・・・・
感磁素子。 6・・・・・・A−Dコンバータ、4・・・・・・車速
センサ。 5・・・・・・ROMカードリーダー、6・・・・・・
キーボード7・・・・・・表示部、8・・・・・・表示
部コントローラ。 以上
FIG. 1 is an electrical block diagram showing a preferred embodiment of the present invention. FIG. 2 is an explanatory diagram illustrating the effect of correcting the direction detection error according to the embodiment shown in FIG. FIG. 6 is a flowchart of an error correction program included in the microcomputer of the embodiment shown in FIG. 1...Microcomputer, 2...
Magnetic sensing element. 6...A-D converter, 4...Vehicle speed sensor. 5...ROM card reader, 6...
Keyboard 7...display section, 8...display section controller. that's all

Claims (1)

【特許請求の範囲】[Claims] 地磁気を検出する感磁要素と、該感磁要素の出力信号を
処理する信号処理回路とでなる方位検出装置に於いて、
前記感磁要素の出力信号に基づき所定タイミング毎に磁
北を示す方位ベクトルを演算し、今回タイミングにおけ
る方位ベクトルの大きさの平均値が前回タイミングにお
ける方位ベクトルの大きさの平均値に対して所定量大き
くなると、前回の全方位ベクトルの中心値に今回の方位
ベクトルの平均値を加減算することにより方位ベクトル
の中心値を変更すべく構成された中心値変更手段を具備
してなる車両用方位検出装置。
In an orientation detection device comprising a magnetically sensitive element that detects earth's magnetism and a signal processing circuit that processes an output signal of the magnetically sensitive element,
An azimuth vector indicating magnetic north is calculated at each predetermined timing based on the output signal of the magnetically sensitive element, and the average value of the magnitude of the azimuth vector at this timing is a predetermined amount with respect to the average value of the magnitude of the azimuth vector at the previous timing. A vehicle azimuth detection device comprising a center value changing means configured to change the center value of the azimuth vector by adding or subtracting the average value of the current azimuth vector to the center value of the previous omnidirectional vector when the center value increases. .
JP26934584A 1984-12-20 1984-12-20 Azimuth detecting device for vehicle Pending JPS61147104A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP26934584A JPS61147104A (en) 1984-12-20 1984-12-20 Azimuth detecting device for vehicle

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP26934584A JPS61147104A (en) 1984-12-20 1984-12-20 Azimuth detecting device for vehicle

Publications (1)

Publication Number Publication Date
JPS61147104A true JPS61147104A (en) 1986-07-04

Family

ID=17471083

Family Applications (1)

Application Number Title Priority Date Filing Date
JP26934584A Pending JPS61147104A (en) 1984-12-20 1984-12-20 Azimuth detecting device for vehicle

Country Status (1)

Country Link
JP (1) JPS61147104A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6243511A (en) * 1985-08-21 1987-02-25 Nissan Motor Co Ltd Vehicle bearing detector
WO2005003683A1 (en) 2003-07-03 2005-01-13 Asahi Kasei Emd Corporation Azimuth measurement device and azimuth measurement method
US7376527B2 (en) 2003-12-22 2008-05-20 Asahi Kasei Emd Corporation Azimuth measuring device

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS58225312A (en) * 1982-06-25 1983-12-27 Nippon Denso Co Ltd Output correction of bearing detector

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS58225312A (en) * 1982-06-25 1983-12-27 Nippon Denso Co Ltd Output correction of bearing detector

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6243511A (en) * 1985-08-21 1987-02-25 Nissan Motor Co Ltd Vehicle bearing detector
WO2005003683A1 (en) 2003-07-03 2005-01-13 Asahi Kasei Emd Corporation Azimuth measurement device and azimuth measurement method
US7340362B2 (en) 2003-07-03 2008-03-04 Asahi Kasei Emd Corporation Azimuth measurement device and azimuth measurement method
US7376527B2 (en) 2003-12-22 2008-05-20 Asahi Kasei Emd Corporation Azimuth measuring device

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