JP2004144528A

JP2004144528A - Underwater sonar system

Info

Publication number: JP2004144528A
Application number: JP2002307781A
Authority: JP
Inventors: Hiroyuki Sadamori; 貞森　博之; Akihisa Fukami; 深見　明久; Kazuhiko Iwata; 岩田　和彦; Kiyotaka Shirakubo; 白窪　清隆; Koichi Ishikawa; 石川　孝一
Original assignee: Hitachi Ltd
Current assignee: Hitachi Ltd
Priority date: 2002-10-23
Filing date: 2002-10-23
Publication date: 2004-05-20

Abstract

<P>PROBLEM TO BE SOLVED: To raise locating precision when locating is performed using a sonar mounted on a ship. <P>SOLUTION: The underwater sonar 100 has a mounting mechanism 21 and an echo sounder transducer 22. The transducer is supported having three degrees of rotation freedom and at least one degree of translation freedom with actuators 3-8 and joints 9-17 which constitute the mounting mechanism, with respect to the ship body 20. Rocking of the transducer with respect to the rocking of the ship body is removed, and high precision of measurement is obtained. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】
本発明は、船舶に搭載される水中用ソーナー装置に関する。
【０００２】
【従来の技術】
船舶に搭載されるソーナー装置では、送受波器が船体と一緒に動揺して目標物の検出精度の低下や、目標物の位置と距離の測定誤差が増加するおそれがあった。そこでこの不具合を解消するために、ソーナー装置が受信信号を変換した後に画面に表示させる場合に、ジャイロ等で測定した船体のロールとピッチのデータを用いて送受波器の測定誤差を算出し信号補正や画像補正を行っていた。
【０００３】
このソーナー装置を船体に取付ける取付方法の例が、特許文献１に記載されている。この特許文献１に記載のソーナー装置は、動揺検出器と平行四辺形のリンク機構により船体に固定された超音波送受波器を有している。そして、動揺検出器と超音波送受波器の軸の方向を一致させて、超音波送受波器の向きを設定している。
【特許文献１】
特開２００１−１５１１９０号公報
【０００４】
【発明が解決しようとする課題】
船体のロールとピッチの情報を用いて信号補正する従来の方法では、送受波器が動揺しても目標物からの反射音を確実に受信できるようにすると、送受波器が大型化しコストが増大するおそれがある。また、信号補正や画像補正に、膨大な計算が必要となり応答性が低下する。また、上記特許文献１に記載のものでは、超音波送受波器を任意の角度に設定できるが、船体の動揺に対する超音波送受波器の動揺を修正できない。そのため、測定精度が低下する。
【０００５】
本発明は上記従来技術の不具合に鑑みなされたものであり、その目的は船体に搭載される水中用ソーナーの測定精度を向上させることにある。
【０００６】
【課題を解決するための手段】
上記目的を達成するための本発明の特徴は、水中に音波を送信して目標物からの反射音を受信する送受波器を備える水中用ソーナー装置において、前記送受波器を船体に取付る取付機構を設け、この取付け機構は船体に対して互いに直交する３軸回りの回転移動と、少なくとも１方向への並進移動を可能にする手段を有することにある。本発明の他の特徴は、水中用ソーナー装置の送受波器が、船体に対して３自由度の回転移動と１自由度以上の並進移動が可能なことにある。
【０００７】
そしてこれらの特徴において、送受波器に、この送受波器の角度位置または送受波器に作用する加速度を検出する検出手段を設け、この送受波器を検出手段の出力に基いて回転移動および並進移動の少なくともいずれかさせて位置決めするのがよい。また、送受波器の回転移動と並進移動を制御する制御手段を設け、この制御手段は船体の波や風による揺れをキャンセルするように送受波器位置を制御するようにするのが好ましい。
【０００８】
【発明の実施の形態】
本発明に係るソナー装置の一実施例を、図１ないし図４を用いて説明する。図４に、水中用ソーナー装置を用いた物体探索の概要を示す。水中用ソーナー装置１００は、水中の目標物４４に向けて音波４３を送信し、その反射波を受信する送受波器２２と、この送受波器２２を船体２０底面に取付ける取付機構２１とを有している。送受波器２２から所定範囲だけに発信された音波４３が、目標物４４に当たって戻るときの時間や方向から目標物４４の有無と位置を検出する。その際、波や風等により船体２０が動揺して測定誤差が生じる。そこで、船体２０と送受波器２２間に取付けた取付機構２１が、船体２０の動揺に対する送受波器２２の動揺をキャンセルする。
【０００９】
この取付機構２１の詳細を、図１により説明する。図１では、水中用ソーナー１００の送受波器２２を直方体状の物体として表している。取付機構２１は、アクチュエータ３〜８とジョイント６〜１７を有している。送受波器２２の上面３箇所に、送受波器２２を船体２０に取付けるため、各個所に２個づつ合計６個の伸縮自在のアクチュエータ３〜８が取付けられている。同じ個所に取り付けた２個のアクチュエータ３、４の組は、Ｖ字をなすように送受波器２の船体２０側取付け端は離して船体２０に取付けられている。アクチュエータ５、６の組、アクチュエータ７、８の組も同様である。各アクチュエータ３〜８の船体２０との接続には、回転可能なジョイント１５〜１７を用いている。一方、アクチュエータ３〜８の船体２０への接続には、これも回転可能なジョイント６〜１１が用いられている。この構成は、スチュワートプラットフォームと呼ばれるもので、３個の回転自由度と３個の並進自由度を有する。
【００１０】
このように、取付け機構２１が３個の回転自由度と３個の併進自由度を有するので、船体２０が波や風によりローリングとピッチングとヨーイングしても、ジョイント９〜１７の３自由度の回転運動により送受波器２２の信号のぶれをキャンセルできる。なお、実際の船体２０の揺れには、上下方向の揺れも重畳されている。
【００１１】
図２に、船体２０が左右に揺れたときの様子を示す。実線は船体２０が水平な状態にあるときを示し、破線は船体２０が傾いた状態を示す。船体２０の傾きを取付機構２１の回転運動によってキャンセルする。このように取付け機構２１が送受波器２４を水平に保つと、送受波器２２の受信信号から船体２０の傾きの影響が取り去られるが、船体２０の上下方向および横方向に、変位Ａ、Ｂが発生する。これらの並進変位Ａ，Ｂにより、送受波器２２の受信信号は影響を受ける。そこでこれらの併進変位Ａ，Ｂをも、取付機構２１を用いてキャンセルする。つまり、アクチュエータ３〜８は並進移動可能なので、回転動作に加えて並進移動させることにより、並進方向の動揺による影響をキャンセルでき、送受波器２２による測定精度を向上できる。また、画像補正に必要な計算量を大幅に減らしたり、水中用ソーナーのメンテナンスを容易に行える。
【００１２】
本発明に係る水中用ソーナーの他の実施例を、図３に示す。本実施例では、上記実施例の水中用ソーナー１００に加えて、保護ドーム３３を船体３０に取り付けている。保護ドーム３３は、取付機構２１および送受波器２２を覆うように設けられている。ところで、従来の水中用ソーナーに保護ドームを適用したときに、回転運動だけで船体２０の動揺をキャンセルしようとすれば、送受波器２２とドーム３３とが干渉する事態が生じるおそれがある。そこでこの干渉を避けようとすれば、送受波器２２の可動範囲が狭くなる。
【００１３】
これに対して本実施例においては、送受波器２２を取付機構２１を用いて並進移動させることができるので、上述した干渉を回避できる。例えば、送受波器２２とドーム３３が干渉する条件の時は、送受波器２２を取付機構２１を用いて上方にへ移動させる。これにより、送受波器２２の可動範囲をドーム３３が無いときと同様まで広くすることができる。本実施例によれば、ドームを設けたので、水中用ソーナーが物体と衝突して故障するのを防止できる。
【００１４】
上記実施例ではアクチュエータとジョイントを用いて送受波器を移動させていたが、並進運動が可能なリニアステージ上に回転運動可能な機構を組合わせるようにしてもよい。この場合、並進方向のストロークを大にすることができるので、例えば、船体と目標物との間に遮へい物があっても、それを避ける位置に送受波器を移動させて目標物の検出や位置測定が可能になる。
【００１５】
なお上記各実施例において、船体または送受波器に角度あるいは加速度を検出するセンサを取付け、このセンサの出力に基づいてアクチュエータを制御すれば、船体の動揺に対する送受波器の動揺をより効果的にキャンセルできる。さらに、並進移動機構を動揺修正だけに用いるのではなく、例えば、船体に対して上下方向の並進移動機構を設けて、送受波器を使用しない時やメンテナンス時に船体の中に送受波器を回収するようにすれば、メンテナスや修理または調整を容易に行える。
【００１６】
【発明の効果】
以上説明したように本実施例によれば、船舶の動揺に対して送受波器を回転変位及び併進変位させることができるので、水中用ソーナーが目標物を検出することおよび目標物の正確な位置測定が可能になる。また、水中用ソーナーの応答性を向上できる。画像補正に必要な計算量を大幅に減らしたり、メンテナンスを容易に行うことができる。
【図面の簡単な説明】
【図１】本発明に係る水中用ソーナーの一実施例の斜視図。
【図２】船体の傾きによる位置ずれを説明する図。
【図３】本発明に係る水中用ソーナーの他の実施例の正面図。
【図４】水中用ソーナーの動作を説明する図。
【符号の説明】
２０…船体、３〜８…アクチュエータ、９〜１７…ジョイント、２１…送受波器の取付機構、２２…送受波器、３３…ドーム、４４…目標物。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an underwater sonar device mounted on a ship.
[0002]
[Prior art]
In a sonar device mounted on a ship, there is a risk that the transducer will swing with the hull, thereby lowering the detection accuracy of the target and increasing the measurement error of the position and distance of the target. Therefore, in order to solve this problem, when the sonar device converts the received signal and displays it on the screen, it calculates the measurement error of the transducer using the roll and pitch data of the hull measured by gyro etc. Correction and image correction were performed.
[0003]
An example of an attachment method for attaching this sonar device to a hull is described in Patent Document 1. The sonar device described in Patent Document 1 has an ultrasonic transducer fixed to a hull by a motion detector and a parallelogram link mechanism. Then, the direction of the axis of the vibration detector and the direction of the axis of the ultrasonic transducer are matched to set the direction of the ultrasonic transducer.
[Patent Document 1]
JP 2001-151190 A
[Problems to be solved by the invention]
With the conventional method of correcting signals using information on the roll and pitch of the hull, it is necessary to ensure that the reflected sound from the target can be received even if the transducer fluctuates. There is a possibility that. In addition, an enormous amount of calculation is required for signal correction and image correction, and responsiveness is reduced. Further, in the configuration described in Patent Document 1, the ultrasonic transducer can be set at an arbitrary angle, but the oscillation of the ultrasonic transducer relative to the oscillation of the hull cannot be corrected. For this reason, the measurement accuracy decreases.
[0005]
SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned disadvantages of the related art, and has as its object to improve the measurement accuracy of an underwater sonar mounted on a hull.
[0006]
[Means for Solving the Problems]
A feature of the present invention for achieving the above object is that in an underwater sonar device including a transducer for transmitting a sound wave into water and receiving a reflected sound from a target, an attachment for attaching the transducer to a hull. A mechanism is provided, wherein the mounting mechanism has means for enabling rotational movement about three axes orthogonal to each other with respect to the hull and translational movement in at least one direction. Another feature of the present invention is that the transducer of the underwater sonar device can perform three degrees of freedom rotation and one or more degrees of freedom translation with respect to the hull.
[0007]
In these features, the transducer is provided with detecting means for detecting the angular position of the transducer or acceleration acting on the transducer, and the transducer is rotated and translated based on the output of the detecting means. The positioning is preferably performed by at least one of the movements. Further, it is preferable that control means for controlling the rotational movement and the translational movement of the transducer is provided, and this control means controls the position of the transducer so as to cancel the sway of the hull due to waves or wind.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
One embodiment of a sonar device according to the present invention will be described with reference to FIGS. FIG. 4 shows an outline of the object search using the underwater sonar device. The underwater sonar device 100 has a transmitter / receiver 22 that transmits a sound wave 43 toward an underwater target 44 and receives a reflected wave thereof, and an attachment mechanism 21 that attaches the transmitter / receiver 22 to the bottom surface of the hull 20. are doing. The presence / absence and position of the target 44 are detected from the time and direction when the sound wave 43 transmitted only from the transmitter / receiver 22 to the predetermined range hits the target 44 and returns. At this time, the hull 20 fluctuates due to waves, wind, and the like, causing a measurement error. Therefore, the mounting mechanism 21 mounted between the hull 20 and the transducer 22 cancels the oscillation of the transducer 22 in response to the oscillation of the hull 20.
[0009]
Details of the mounting mechanism 21 will be described with reference to FIG. In FIG. 1, the transducer 22 of the underwater sonar 100 is represented as a rectangular parallelepiped object. The mounting mechanism 21 has actuators 3 to 8 and joints 6 to 17. In order to attach the transducer 22 to the hull 20 at three places on the upper surface of the transducer 22, a total of six extensible actuators 3 to 8, two at each location, are attached. A set of two actuators 3 and 4 attached to the same place is attached to the hull 20 with the attachment end on the hull 20 side of the transducer 2 so as to form a V shape. The same applies to the set of actuators 5 and 6, and the set of actuators 7 and 8. Rotatable joints 15 to 17 are used to connect the actuators 3 to 8 to the hull 20. On the other hand, joints 6 to 11 which are also rotatable are used for connecting the actuators 3 to 8 to the hull 20. This configuration is called a Stewart platform and has three rotational degrees of freedom and three translational degrees of freedom.
[0010]
Thus, since the mounting mechanism 21 has three rotational degrees of freedom and three translational degrees of freedom, even if the hull 20 is rolled, pitched, and yawed by waves or wind, the joints 9 to 17 have three degrees of freedom. The rotational motion can cancel the blur of the signal of the transducer 22. Note that the actual sway of the hull 20 is also superimposed on the sway in the vertical direction.
[0011]
FIG. 2 shows a state where the hull 20 swings right and left. A solid line indicates a state where the hull 20 is in a horizontal state, and a broken line indicates a state where the hull 20 is inclined. The inclination of the hull 20 is canceled by the rotation of the mounting mechanism 21. When the mounting mechanism 21 keeps the transducer 24 horizontal as described above, the influence of the inclination of the hull 20 is removed from the reception signal of the transducer 22, but the displacements A, B in the vertical and lateral directions of the hull 20 are removed. Occurs. The received signals of the transducer 22 are affected by these translation displacements A and B. Therefore, these translational displacements A and B are also canceled using the mounting mechanism 21. That is, since the actuators 3 to 8 can be translated, by performing translation in addition to the rotation operation, the influence of the fluctuation in the translation direction can be canceled, and the measurement accuracy by the transducer 22 can be improved. Further, the amount of calculation required for image correction can be greatly reduced, and maintenance of the underwater sonar can be easily performed.
[0012]
Another embodiment of the underwater sonar according to the present invention is shown in FIG. In this embodiment, a protection dome 33 is attached to the hull 30 in addition to the underwater sonar 100 of the above embodiment. The protection dome 33 is provided so as to cover the mounting mechanism 21 and the transducer 22. By the way, when the protection dome is applied to the conventional underwater sonar, if the movement of the hull 20 is canceled only by the rotational movement, there is a possibility that the transceiver 22 and the dome 33 may interfere with each other. Therefore, to avoid this interference, the movable range of the transducer 22 becomes narrow.
[0013]
On the other hand, in the present embodiment, since the transducer 22 can be translated using the attachment mechanism 21, the above-described interference can be avoided. For example, under the condition where the transducer 22 interferes with the dome 33, the transducer 22 is moved upward by using the mounting mechanism 21. Thereby, the movable range of the transducer 22 can be widened to the same extent as when the dome 33 is not provided. According to the present embodiment, since the dome is provided, it is possible to prevent the underwater sonar from colliding with an object and failing.
[0014]
In the above embodiment, the transducer is moved using the actuator and the joint, but a mechanism capable of rotational movement may be combined on a linear stage capable of translational movement. In this case, since the stroke in the translation direction can be increased, for example, even if there is a shield between the hull and the target, the transducer is moved to a position where it is avoided to detect the target, Position measurement becomes possible.
[0015]
In each of the above embodiments, if a sensor for detecting an angle or acceleration is attached to the hull or the transducer, and the actuator is controlled based on the output of this sensor, the sway of the transducer with respect to the hull can be more effectively controlled. Can be canceled. Furthermore, instead of using the translation mechanism only for shaking correction, for example, a vertical translation mechanism is provided for the hull, and the transducer is collected in the hull when the transducer is not used or during maintenance. This will facilitate maintenance, repair or adjustment.
[0016]
【The invention's effect】
As described above, according to the present embodiment, the transducer can be rotationally and translationally displaced in response to the motion of the ship, so that the underwater sonar can detect the target and correct the position of the target. Measurement becomes possible. In addition, the responsiveness of the underwater sonar can be improved. The amount of calculation required for image correction can be significantly reduced, and maintenance can be easily performed.
[Brief description of the drawings]
FIG. 1 is a perspective view of an embodiment of an underwater sonar according to the present invention.
FIG. 2 is a view for explaining a displacement caused by a tilt of a hull.
FIG. 3 is a front view of another embodiment of the underwater sonar according to the present invention.
FIG. 4 is a diagram illustrating the operation of the underwater sonar.
[Explanation of symbols]
Reference Signs List 20: Hull, 3-8: Actuator, 9-17: Joint, 21: Transceiver mounting mechanism, 22: Transceiver, 33: Dome, 44: Target.

Claims

An underwater sonar device including a transducer for transmitting sound waves into water and receiving a reflected sound from a target object is provided with an attachment mechanism for attaching the transducer to a hull, and the attachment mechanisms are mutually attached to the hull. An underwater sonar device comprising means for enabling rotational movement about three orthogonal axes and translational movement in at least one direction.

In an underwater sonar device including a transmitter / receiver for transmitting a sound wave into water and receiving a reflected sound from a target object, the transmitter / receiver has a rotational movement of three degrees of freedom and a translation of one or more degrees of freedom with respect to the hull. An underwater sonar device characterized by being movable.

The transmitter / receiver is provided with detecting means for detecting an angular position of the transmitter / receiver or an acceleration acting on the transmitter / receiver, and the transmitter / receiver is provided with at least one of rotational movement and translational movement based on an output of the detecting means. The underwater sonar device according to claim 1 or 2, wherein the underwater sonar device is positioned by being moved.

2. The apparatus according to claim 1, further comprising control means for controlling a rotational movement and a translational movement of the transducer, wherein the control means controls the position of the transducer so as to cancel the sway of the hull due to waves or wind. 4. The underwater sonar device according to any one of items 3 to 3.