JPS603556A - Method for measuring ship speed especially, in ultrasonic current direction and current speed meter - Google Patents

Method for measuring ship speed especially, in ultrasonic current direction and current speed meter

Info

Publication number
JPS603556A
JPS603556A JP11006683A JP11006683A JPS603556A JP S603556 A JPS603556 A JP S603556A JP 11006683 A JP11006683 A JP 11006683A JP 11006683 A JP11006683 A JP 11006683A JP S603556 A JPS603556 A JP S603556A
Authority
JP
Japan
Prior art keywords
ultrasonic wave
gate
speed
output
transmitter
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
JP11006683A
Other languages
Japanese (ja)
Other versions
JPH0227624B2 (en
Inventor
Masahiko Tsunoda
正彦 角田
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.)
Kaijo Denki Co Ltd
Marine Instr Co Ltd
Original Assignee
Kaijo Denki Co Ltd
Marine Instr 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 Kaijo Denki Co Ltd, Marine Instr Co Ltd filed Critical Kaijo Denki Co Ltd
Priority to JP11006683A priority Critical patent/JPS603556A/en
Publication of JPS603556A publication Critical patent/JPS603556A/en
Publication of JPH0227624B2 publication Critical patent/JPH0227624B2/ja
Granted legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
    • G01P5/00—Measuring speed of fluids, e.g. of air stream; Measuring speed of bodies relative to fluids, e.g. of ship, of aircraft
    • G01P5/24—Measuring speed of fluids, e.g. of air stream; Measuring speed of bodies relative to fluids, e.g. of ship, of aircraft by measuring the direct influence of the streaming fluid on the properties of a detecting acoustical wave
    • G01P5/241—Measuring speed of fluids, e.g. of air stream; Measuring speed of bodies relative to fluids, e.g. of ship, of aircraft by measuring the direct influence of the streaming fluid on the properties of a detecting acoustical wave by using reflection of acoustical waves, i.e. Doppler-effect
    • G01P5/244—Measuring speed of fluids, e.g. of air stream; Measuring speed of bodies relative to fluids, e.g. of ship, of aircraft by measuring the direct influence of the streaming fluid on the properties of a detecting acoustical wave by using reflection of acoustical waves, i.e. Doppler-effect involving pulsed waves
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S15/00—Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems
    • G01S15/02—Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems using reflection of acoustic waves
    • G01S15/50—Systems of measurement, based on relative movement of the target
    • G01S15/58—Velocity or trajectory determination systems; Sense-of-movement determination systems
    • G01S15/60—Velocity or trajectory determination systems; Sense-of-movement determination systems wherein the transmitter and receiver are mounted on the moving object, e.g. for determining ground speed, drift angle, ground track
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S15/00—Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems
    • G01S15/02—Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems using reflection of acoustic waves
    • G01S15/06—Systems determining the position data of a target
    • G01S15/08—Systems for measuring distance only
    • G01S15/10—Systems for measuring distance only using transmission of interrupted, pulse-modulated waves
    • G01S15/18—Systems for measuring distance only using transmission of interrupted, pulse-modulated waves wherein range gates are used
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S15/00—Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems
    • G01S15/66—Sonar tracking systems

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • General Physics & Mathematics (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Remote Sensing (AREA)
  • Multimedia (AREA)
  • Aviation & Aerospace Engineering (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Measurement Of Velocity Or Position Using Acoustic Or Ultrasonic Waves (AREA)
  • Indicating Or Recording The Presence, Absence, Or Direction Of Movement (AREA)

Abstract

PURPOSE:To measure a ground speed of a ship by catching effectively, appropriately and usefully a reflected wave coming back from the sea bottom of a wide range, which is obtained by an ultrasonic wave having a directivity, and extracting a Doppler component. CONSTITUTION:When the transmitting pulse from a transmitter 4 is transmitted to a transmitter and receiver 6 through a transmission and reception coupling circuit 5 and an ultrasonic wave is sent out into the water, the reflected wave coming back to the transmitter and receiver 6 is amplified by a receiving part 7 through the transmission and reception coupling circuit 5. It is applied to an operating part 9, DELTAt2 is calculated from the expression, and when its output is applied to a t0 operating part 14 for determining a transmitting pulse width, on the other hand, the output of a DELTAt setting part 13 which has set a sampling time is applied to this operating part 14, therefore, the transmitting pulse width having a relation of t0>=DELTAt2+DELTAt is calculated from both data, and the transmitting part 4 is driven by its output signal. Subsequently, a gate generating part 10 opens the gate of a gate circuit 11, and the signal is sent to a Doppler counter 12 of the post-stage.

Description

【発明の詳細な説明】 本発明は超音波を利用して流速流向及び船速を測定する
装置において、とくに船速をより一層精度の良い測定結
果を得るための改良された測定方法に関するものである
。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device that uses ultrasonic waves to measure current velocity, direction, and ship speed, and in particular relates to an improved measurement method for obtaining even more accurate ship speed measurement results. be.

超音波を用いて流速と流向（以下単に流速という）及び
船速を測定する場合、第１図に示すように水面１に対し
て垂直の方向から角度θだけ指向ビームを傾け、船２に
装備した送受波器（図示を省略）から海底３に向って超
音波を送出し、海底及び任意に設定した深度層からの反
射波を受信しその反射波の中に含まれる船速ならびに流
速に基づいて生ずるドツプラー効果による周波数の偏差
すなわちドツプラー成分を検出して、偏差値から数値計
算を行って流速と船速を演算することは周知の通りであ
り、測定装置は多く実用されている。When measuring the flow velocity and direction (hereinafter simply referred to as flow velocity) and ship speed using ultrasonic waves, as shown in Figure 1, the directional beam is tilted by an angle θ from the direction perpendicular to the water surface 1, and the beam is installed on the ship 2. A transducer (not shown) transmits ultrasonic waves toward the seabed 3, receives reflected waves from the seabed and arbitrarily set depth layers, and based on the ship speed and current speed contained in the reflected waves. It is well known that the frequency deviation due to the Doppler effect, that is, the Doppler component, which occurs in the water is detected, and numerical calculations are performed from the deviation value to calculate the current velocity and ship speed, and many measuring devices are in practical use.

ところでこの種の測定装置においてとくに船の対地速度
を検出するに当って反射波はどのような経路を通って帰
来するかをみると、送受波器は指向角を持っているので
、指向角に含まれる範囲全体にわたり、距離の近い所か
ら順次遠い所に及び、それぞれ違った経路を通って帰来
する。By the way, in this type of measuring device, especially when detecting the ground speed of a ship, if we look at what route the reflected waves take to return, the transducer has a directional angle, so the directional angle Over the entire included range, the distances range from near to far, each returning via a different route.

すなわち第１図において、送受波器指向性の半減半角を
Δθとすれば、最も近い距離Ａから順次に最も遠い距’
Ｒｈの範囲に含まれる海底３から反射波が帰来する。In other words, in Fig. 1, if the half angle of the directivity of the transducer is Δθ, then the distance A is the closest to the farthest distance '
Reflected waves return from the seabed 3 included in the range of Rh.

本来、求めたいドツプラー成分はビーム中心方向である
距離扁からの反響音に含まれるものであり、これに対し
てＡに対するものはドツプラー成分が少なく、馬に対す
るものはドツプラー成分が多くなるから、扁に対するも
の以外は誤差となる。Originally, the Doppler component that we want to find is included in the echo from the distance plane, which is the beam center direction.On the other hand, there are few Doppler components for A, and there are many Doppler components for the horse. Anything other than that for which it is applied will be an error.

実際問題としては、馬に対する反射波だけを得ることは
不可能であるから、Ａから馬までの全ての反射波を取出
し、それらの平均をめてほぼ扁に対する反射波に近づけ
る必要がある。In practice, it is impossible to obtain only the reflected waves from the horse, so it is necessary to extract all the reflected waves from A to the horse and average them to approximate the reflected waves from the horse.

本発明はこの対処策として如何なる方法をとればよいか
という点に関するもので、以下その根拠について述べ、
実施例に触れる。The present invention relates to what method should be taken as a countermeasure for this problem, and the basis thereof will be described below.
Let's touch on an example.

送受波器面から海底までの距離をｄ１ビームの傾きを０
１指向性の半減半角をΔθとした場合、中心ビーム上で
の海底までの距離を扁、最大幅のビーム方向（すなわち
θに対し±Δθの方向）の海底までの距離Ａ及び為とす
ると、 （１）と（２）から 為と４の関係は−１，ン４であるから、送受波器から送
られた超音波が扁の経路において海底に到達してから、
馬の経路において海底に到達する迄には、’２　Ａ　’
）　Ｆ　Ｍ　’ｉ：”“７１６１１６ＲｆｔｔｌＪｔ、
“　１け遅れる。The distance from the transducer surface to the seabed is d1 The inclination of the beam is 0.
When the half-angle of directivity is Δθ, the distance to the seabed on the center beam is A, and the distance A and the seafloor in the direction of the maximum beam width (i.e., the direction of ±Δθ with respect to θ) is: From (1) and (2), the relationship between tame and 4 is -1, n4, so after the ultrasonic wave sent from the transducer reaches the ocean floor on the flat path,
By the time the horse's path reaches the ocean floor, '2 A'
) F M 'i:""716116RfttlJt,
“I'm one place behind.

馬と４の差Δ爲は、（３）式を用いてめると次に示す（
４）式となる。The difference ∆ between horse and 4 can be calculated using equation (3) as shown below (
4) Equation becomes.

Δ為＝４−Ａ そこでΔ４を時間Δｔ２に変換すると 但しここで音速をＣとする。∆ = 4-A So, if we convert Δ4 to time Δt2, However, let C be the speed of sound here.

（５）式から明らかな通り、一番最初に反射波が帰来す
る点までの距離扁が判れば、音速Ｃとθ及びΔθは既知
であるからΔｔ、をめることができる。As is clear from equation (5), if the distance to the point where the reflected wave first returns is known, Δt can be calculated since the sound speed C, θ, and Δθ are known.

次に経路へから烏に対する反射波を有効にサンプリング
する時間をΔｔとすると、送信パルス幅ｔｏは前述のΔ
ｔ、を考慮してｔ。≧Δｔ、＋Δｔ　なる関係を持つよ
うに決めればよい。Next, if the time to effectively sample the reflected waves from the path to the crow is Δt, the transmission pulse width to is the above-mentioned Δ
t, considering t. It may be determined that the relationship is ≧Δt, +Δt.

すなわち第２図に示すように、送信パルス幅ｔ。That is, as shown in FIG. 2, the transmission pulse width t.

について扇から為に及ぶ範囲の反射波は階段的に捕捉さ
れるから、図中のハツチングをした部分Δを時間をサン
プリングする時間に定めれば、無駄がなく必要とするデ
ータを最も有効適切に集めることができる。Since the reflected waves in the range from the fan to the fan are captured in a stepwise manner, if the hatched part Δ in the figure is set as the sampling time, the necessary data can be collected most effectively and appropriately without wasting any waste. can be collected.

以上をふまえて本発明を実施する場合の手段を第３図を
参照して説明する。Based on the above, means for carrying out the present invention will be explained with reference to FIG.

４は送信部、５は送受結合回路、６は送受波器、７は受
信部であり、送信部４から送信パルスを送受結合回路５
を介して送受波器６に送り、水中に超音波を送出するに
１送受波器６に帰来する反射波は送受結合回路５を通っ
て受信部７で増幅されるように構成しであるのは、通常
の魚群探知機などの水中物体探知装置におけるものと全
く同じである。4 is a transmitting section, 5 is a transmitting/receiving coupling circuit, 6 is a transducer, and 7 is a receiving section.
The ultrasonic wave is sent to the transducer 6 via the transducer 6, and the reflected wave that returns to the transducer 6 passes through the transducer coupling circuit 5 and is amplified by the receiver 7. is exactly the same as in an underwater object detection device such as a normal fish finder.

旦は処理部であり、Δｔ２の演算部９、ゲート発７ｆ［
１０、ゲート回路１１、ドツプラーカウンター１２、Δ
を設定部１３、ｔｏ演算部１４などで構成されている。1 is a processing unit, a calculation unit 9 of Δt2, a gate output 7f[
10, gate circuit 11, Doppler counter 12, Δ
It is composed of a setting section 13, a to calculation section 14, and the like.

さて受信部７の出力がΔｔ２の演算部９に印加されると
、受信部７の出力に含まれる情報に基づいて、前記の（
５）式からΔｔ２が演算され、その出力は送信パルス幅
を決めるｔ。演算部１４に印加されると、一方ではこの
ｔ。演算部１４にはサンプリング時間を設定したΔを設
定部１３の出力が印加されるので、両方のデータからｔ
。≧Δｔ２＋Δｔの関係を有する送信パルス幅が演算さ
れ、その出力信号で送信部４が駆動される。Now, when the output of the receiving section 7 is applied to the calculation section 9 of Δt2, based on the information included in the output of the receiving section 7, the above (
5) Δt2 is calculated from the equation, and its output is t, which determines the transmission pulse width. When applied to the calculation unit 14, on the one hand, this t. Since the output of the setting unit 13 is applied to the calculation unit 14, Δ, which is the sampling time set, is calculated by t from both data.
. A transmission pulse width having a relationship of ≧Δt2+Δt is calculated, and the transmitter 4 is driven by the output signal.

そしてゲート発生部１０は、前記ｔ。演算部１４からの
信号を受け、前記Δｔ、演算部９の出力の終端からスタ
ートし、Δｔだけ継続するゲートをつくる信号を発生し
てゲート回路１１のゲートを開き、ゲートが開かれてい
る時間だけ受信部７の反射波がサンプリングされて、後
段のドツプラーカウンター１２に送られる。かくして該
ドツプラーカウンターの出力には反射波に含まれたドツ
プラー成分が検出され、船速演算部（図示せず）に送ら
れる。Then, the gate generating section 10 performs the above-mentioned t. Upon receiving the signal from the calculation unit 14, the gate of the gate circuit 11 is opened by generating a signal to create a gate that starts from the end of the output of the calculation unit 9 and continues for Δt, and the gate is opened for a period of time. The reflected waves of the receiving section 7 are sampled and sent to the Doppler counter 12 at the subsequent stage. In this way, the Doppler component contained in the reflected wave is detected in the output of the Doppler counter and sent to a ship speed calculation section (not shown).

以上説明の通り本発明は、とくに船の対地速度を検出す
る際、指向性を有する超音波によって得られる広い範囲
の海底から帰来する反射波を有効適切に無駄なく捕促し
、ドツプラー成分を取り出すことができる。As explained above, the present invention is particularly aimed at detecting the ground speed of a ship by effectively and appropriately capturing the reflected waves returned from the seabed over a wide range obtained by directional ultrasonic waves without waste, and extracting the Doppler component. I can do it.

なお、実際には船のローリングやピッチングのため送受
波器から送出するビームの傾きθの値が変るが、一般に
は船の前後、左右など２ビ一ム方式を採用しているので
とくに問題はない。In reality, the value of the inclination θ of the beam sent out from the transducer changes due to the rolling and pitching of the ship, but since a two-beam system is generally used for the front, rear, left and right sides of the ship, this is not a particular problem. do not have.

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

第１図は測定要領の説明図。 第２図は海底からの反射の関係図。 第３図は実施例の系統図。 ４・・・送信部、５・・・送受結合回路、６・・・送受
波器、７・・・受信部、旦・・・処理部、９・・・Δｔ
２の演算部、１０・・・ゲート発生部、１１・・・ゲー
ト回路、１２・・・ドツプラーカウンター、 １３・・・Δを設定部、１４・・・ｔｏ演算部。 特許出願人 海上電機株式会社 第　１　ｍｌ 第　２　臣 第　５　図 乙FIG. 1 is an explanatory diagram of the measurement procedure. Figure 2 is a diagram showing the relationship between reflections from the ocean floor. FIG. 3 is a system diagram of the embodiment. 4... Transmitting unit, 5... Transmitting/receiving coupling circuit, 6... Transducer/receiver, 7... Receiving unit, Dan... Processing unit, 9... Δt
2 arithmetic unit, 10... gate generation unit, 11... gate circuit, 12... Doppler counter, 13... Δ setting unit, 14... to arithmetic unit. Patent Applicant Kaiyo Denki Co., Ltd. No. 1 ml No. 2 Minister No. 5 Figure B

Claims (1)

【特許請求の範囲】 垂直方向に対して適宜に設定した角度θだけビームの中
心方向を傾け、かつ半減半角がΔθなる指向特性を有す
る超音波を送出し、海底及び設定した深度層からの反射
波を受信し、反射波に含まれるドツプラー成分を検出し
て船速、流速などを算出するようにした測定装置におい
て、とくに船速の測定に当り、角度（θ−Δθ）におけ
る海底までの距離がＡ１角度（θ＋ΔＯ）における海底
までの距離が為であるとき、両者の距離を超音波が伝播
するに要する時間の差Δｔ、を、音速をＣとして Δｔ、−８−（÷も４鼾−１） から算出し、かつ反射波を処理する時間Δｔを設定して
、前記Δｔ、とΔｔの値を基にし、送出する超音波のパ
ルス幅ｔ。を ｔｏ≧Δｔ、＋Δｔ に設定すると共に、Δを時間だけゲートを開いて反射波
をサンプリングして処理するようにしたことを特徴とす
る超音波流向流速計におけるとくに船速を測定する方法
。[Claims] The central direction of the beam is tilted by an appropriately set angle θ with respect to the vertical direction, and an ultrasonic wave having a directional characteristic with a half-angle of Δθ is transmitted, and the ultrasonic wave is reflected from the seabed and a set depth layer. A measuring device that receives waves and detects the Doppler component included in the reflected waves to calculate ship speed, current speed, etc. In particular, when measuring ship speed, the distance to the seabed at an angle (θ - Δθ) is used. is the distance to the seabed at angle A1 (θ + ΔO), then the difference Δt in time required for the ultrasonic wave to propagate both distances is expressed as Δt, -8-(÷4snoring- 1) Calculate the time Δt for processing the reflected waves and set the pulse width t of the ultrasonic wave to be transmitted based on the values of Δt and Δt. A method for measuring ship speed in an ultrasonic current meter, characterized in that to≧Δt, +Δt, and a gate is opened for the time Δ to sample and process reflected waves.
JP11006683A 1983-06-21 1983-06-21 Method for measuring ship speed especially, in ultrasonic current direction and current speed meter Granted JPS603556A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP11006683A JPS603556A (en) 1983-06-21 1983-06-21 Method for measuring ship speed especially, in ultrasonic current direction and current speed meter

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP11006683A JPS603556A (en) 1983-06-21 1983-06-21 Method for measuring ship speed especially, in ultrasonic current direction and current speed meter

Publications (2)

Publication Number Publication Date
JPS603556A true JPS603556A (en) 1985-01-09
JPH0227624B2 JPH0227624B2 (en) 1990-06-19

Family

ID=14526192

Family Applications (1)

Application Number Title Priority Date Filing Date
JP11006683A Granted JPS603556A (en) 1983-06-21 1983-06-21 Method for measuring ship speed especially, in ultrasonic current direction and current speed meter

Country Status (1)

Country Link
JP (1) JPS603556A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105628960A (en) * 2014-10-29 2016-06-01 北京强度环境研究所 Speed-measuring device of underwater test ship speed simulating system

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0478731U (en) * 1990-11-22 1992-07-09

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS59230165A (en) * 1983-06-13 1984-12-24 Marine Instr Co Ltd Measuring method of current speed and current direction by ultrasonic current and direction meter

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS59230165A (en) * 1983-06-13 1984-12-24 Marine Instr Co Ltd Measuring method of current speed and current direction by ultrasonic current and direction meter

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105628960A (en) * 2014-10-29 2016-06-01 北京强度环境研究所 Speed-measuring device of underwater test ship speed simulating system

Also Published As

Publication number Publication date
JPH0227624B2 (en) 1990-06-19

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