JP2003344536A - Ultrasonic inspection equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ultrasonic inspection equipment which can grasp more accurate states in water and of a water bottom by distinguishing an object in water from the water bottom and displaying distances and azimths of these reflecting objects and the water bottom, while keeping a merit that the constitution is simple and low in cost. <P>SOLUTION: The ultrasonic inspection equipment is provided with: a transmitting part for transmitting an ultrasonic wave signal; a receiving part provided with receiving elements for receiving a reflected wave of the transmitted signal from the object and outputting a received signal; an azimuth detecting part for detecting an azimuth of the object from arrangement of the receiving elements and phase difference of received signals output from the receiving elements; a distance and reflection intensity detecting part for detecting a distance from the object and reflection intensity, from an appearing time and an amplitude of the received signal; a display processing part for displaying the object on an image plane wherein the detected azimuth, distance and reflection intensity are used as data for display; and a water bottom judging part for judging the water bottom, on the basis of reflected signal intensity output from the reflection intensity detecting part. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic probe device capable of detecting a two-dimensional or three-dimensional position of a reflective object such as a fish body, and particularly, while maintaining a simple and inexpensive structure, The present invention relates to an ultrasonic probing apparatus that improves the accuracy and resolution of detection of water bottoms and objects in water.

[0002]

2. Description of the Related Art A conventional simple fish finder emits ultrasonic waves into water (hereinafter, water is also referred to as undersea) from an ultrasonic transducer attached to the bottom of a ship or the like to detect a fish body or the like. The reflected wave generated by the underwater reflecting object is received, and the time required from transmission to reception, that is, the time required for the ultrasonic wave to make a round trip is detected from the distance to the reflecting object. Since this simple fish finder cannot detect the arrival direction of the reflected wave, that is, the azimuth of the reflecting object, all the reflecting objects are treated as if they were right under the ship. The above is called the first conventional technology.

In order to detect not only the distance to the reflecting object but also its direction, a large number of ultrasonic transducers are arrayed and sequentially operated in the order of arrangement, or electronic scanning is performed, or a single ultrasonic transducer is used. It is necessary to perform a mechanical scan in which the orientation is changed. The electronic scanning arrangement described above requires a large number of ultrasonic transducers, which makes the device complex and expensive. Further, in the above mechanical scanning configuration, a mechanical scanning mechanism is required, so that the device is also complicated and expensive.

The applicant's prior application (Japanese Patent Laid-Open No. 2001-999
No. 31) discloses an ultrasonic probing apparatus capable of detecting the two-dimensional or three-dimensional position of a reflecting object such as a fish body in the sea by using a small number of ultrasonic transducers. This ultrasonic exploration device receives the reflected waves of the transmitted ultrasonic waves by a plurality of receiving elements and reflects them from the azimuth function determined by the shape and arrangement of each receiving element and the phase difference of the received signal of each receiving element. The azimuth detector is provided to detect the azimuth of the object that generated the wave. In addition, this device includes a distance detection unit that detects a distance to a reflecting object and a reflection intensity from a time required for transmitting the ultrasonic wave to receiving the reflected wave and the amplitude of the received reflected wave, and each of the above. The display unit includes a display unit that two-dimensionally or three-dimensionally displays a combination of the azimuth and the distance detected by the detection unit. As described above, the multidimensional position of the reflective object is detected by detecting the azimuth of the reflective object in addition to the distance to the reflective object and the reception intensity of the related art. The above is referred to as the second related art.

In this second prior art ultrasonic probe,
For example, as shown in FIG. 4, rectangular ultrasonic transducers TD1 and TD2 are arranged in the x-axis direction (the port side of the ship) at a distance L from the bottom of the ship. The ultrasonic transmitters TD1 and TD2 radiate the same transmission signal at the same time. It is assumed that the reflecting object W exists in the direction of the azimuth angle θ _X , which is R away from the center of the transducer TD1. The other ultrasonic transducer TD2 and the reflecting object W
If the distance between and is R + δR, then δR = Lsin θ _X. C is the propagation velocity of the ultrasonic wave generated in the reflecting object W.
If the time difference δt from when one ultrasonic transducer TD1 receives the reflected wave to when the other ultrasonic transducer TD2 receives the reflected wave, then δt = δ
We obtain R / c = Lsin θ _X / c.

By setting the distance L and the frequency of the ultrasonic signal in advance so that the time difference δt becomes smaller than the half cycle of the ultrasonic wave received signal, the time difference at the time of the reception can be adjusted by each ultrasonic transducer. It can be detected from the phase difference between the received signals. As a transmission signal, several tens of kHz
A burst-like waveform in which a sinusoidal carrier wave in the ultrasonic band of z to several hundred kHz lasts for several tens of cycles is used. In the case of a ship, for example, in the case of a ship, the multi-dimensional display of the reflecting object is such that, when the port side direction is the x axis, the depth direction is the y axis, and the traveling direction of the ship is the z axis (time axis t), the xy section, the ty section, It is displayed by a tx section or the like having a constant depth.

According to the above-described ultrasonic probe of the second prior art, the two-dimensional or three-dimensional position of the reflecting object is detected over a certain angle range such as the port side direction by using at least two ultrasonic transducers. be able to.

FIG. 5 is an example of a three-dimensional display screen in the configuration of the ultrasonic detecting device of the second prior art as shown in FIG. As the three orthogonal axes, the x-axis is set in the port side direction of the ship, the y-axis is set in the depth direction, and the z-axis or the time axis t is set in the traveling direction of the ship. The upper left display screen a) is a ty cross section of the ship, the upper right display screen b) is an xy cross section, and the lower left display screen c) is a tx cross section. A1, b1, c1 in each section
Is the same reflective object detected at the current time point, and a
4 and b4 indicate the seabed.

[0009]

Since the ultrasonic probe of the above-mentioned first prior art cannot detect the direction of the reflecting object, the reflecting object is treated as if it were right underneath the ship, and the underwater is detected. It is not possible to display the exact position of the reflective object. For this reason, there is a problem in that when fishing boats are operated, the position of the fishing net and the actual direction of the school of fish are slightly displaced, the number of fish caught on the net is smaller than expected, and the catch cannot be increased.

Further, in order to detect not only the distance to the reflecting object but also its direction, a large number of ultrasonic transducers are arranged and are sequentially operated in the order of arrangement, or electronic scanning is performed, or a single ultrasonic wave is used. It is necessary to perform a mechanical scan that changes the orientation of the transducer. The electronic scanning arrangement described above requires a large number of ultrasonic transducers, which makes the device complex and expensive. Further, in the above mechanical scanning configuration, since a mechanical scanning mechanism is required, there is also a problem that the device becomes complicated and expensive.

In the second prior art ultrasonic probe,
The ultrasonic signal is transmitted and received by the two ultrasonic transducers, and the ultrasonic signal is transmitted and received once by the two ultrasonic transducers to transmit and receive the ultrasonic signal only once. The data is acquired. By the way, the water bottom display in the ultrasonic probe of the second prior art is not a display in a color corresponding to the intensity of the reflection signal from the water bottom, and there is a problem that it is difficult to determine the bottom quality of the water bottom.

Therefore, an object of the present invention is to distinguish between a reflecting object in water and the bottom of the water, and to display the distance and direction of the reflecting object and the bottom of the water, while maintaining the advantage that the structure is simple and inexpensive. Therefore, it is to provide an ultrasonic probing apparatus capable of more accurately grasping the state of water and the bottom of the water.

[0013]

An ultrasonic detecting apparatus of the present invention comprises a transmitting section having a transmitting element for transmitting an ultrasonic signal,
A receiving unit including a plurality of receiving elements that receive a reflected wave of the transmitted ultrasonic signal from the object and output a received signal,
An azimuth detecting unit that detects the azimuth of an object from the arrangement of a plurality of receiving elements and the phase difference of the received signals output from each receiving element, and a distance that detects the distance to the object and the reflection intensity from the output time and amplitude of the received signal. An ultrasonic exploration device including a reflection intensity detection unit and a display processing unit that displays an object on the screen using the detected azimuth, distance, and reflection intensity as display data, which is output from the distance / reflection intensity detection unit. The bottom of the water is determined based on the intensity of the reflected signal.

Further, according to the invention of claim 2, the display processing section comprises:
The reflection signal determined to be the water bottom by the water bottom determination unit is displayed in a specific color. Further, in the invention of claim 3, the display processing unit is configured to display the reflection signal determined as the water bottom by the water bottom determination unit in a color corresponding to the water bottom depth.

In the invention of claim 4, the display processing unit is configured to magnify and display the reflection signal determined to be the water bottom by the water bottom determination unit.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described based on examples. FIG. 1 is a block diagram showing a configuration of an ultrasonic probe device according to an embodiment of the present invention. This ultrasonic survey apparatus includes a control unit CNT, a transmission unit TX, a single circuit IS1,
IS2, ultrasonic transducers TD1 and TD2, amplifier circuits AMP1 and AMP2, sampling circuit SPL1,
SPL2, complex signal synthesis circuits CMPX1, CMPX2,
Phase difference detection circuit ARG, addition circuit ADD, absolute value circuit A
It is equipped with a BS, a water bottom determination circuit BTM, a digital signal processor DSP, and a display device DIS.

Under the control of the control unit CNT, the transmission unit TX generates an ultrasonic transmission signal. This transmission signal has a burst-like waveform in which a sine wave carrier in the ultrasonic band of several tens of kHz to several hundreds of kHz lasts for several tens of cycles. The ultrasonic transmission signal is supplied to each of the two ultrasonic transducers TD1 and TD2 after passing through the single-circuit circuits IS1 and IS2 that transmit the signal only in one direction.
They are simultaneously emitted to the outside sea and the like. Reflected waves radiated into the sea and generated by a fish body in the sea are received by the ultrasonic transducers TD1 and TD2 which are commonly used for transmission and reception, and are amplified by the amplifier circuits AMP1 and AMP2.

The reception reflection signals a ₁ and a ₂ amplified by the amplifier circuits AMP1 and AMP2 are converted into sampling circuits SPL1 and SPL1, respectively.
In SPL2, the first and second sampling signals sp
_It is sampled by _i , sp _q and converted into a digital signal. The digital reception signals p ₁ and q ₁ output from the first sampling circuit SPL1 are digital complex signals r ₁ = p _{1 in} the complex signal synthesis circuit CMPX1 in the subsequent stage.
It is converted to + jq ₁ and supplied to the phase difference detection circuit ARG and the addition circuit ADD. Similarly, the digital reception signals p ₂ , q ₂ output from the second sampling circuit SPL2
Is converted into a digital complex signal r ₂ = p ₂ + jq ₂ in the complex signal synthesizing circuit CMPX2 in the subsequent stage and supplied to the phase difference detecting circuit ARG and the adding circuit ADD.

In the phase difference detection circuit ARG, the deviation angle g of the received reflection signals a ₁ and a ₂ is calculated from the complex conjugate product r ₁ · r ₂ ^{* of} the digital complex signals r ₁ and r _2, and the digital signal It is supplied to the processor DSP. In the adder circuit ADD, the digital complex signals r ₁ and r ₂ are added, the absolute value s of the added value h is calculated by the absolute value circuit ABS, and the water bottom determination circuit BTM and the digital signal processor DS are added.
And P.

In the water bottom judgment circuit BTM, it is judged whether or not the absolute value s supplied to the digital signal processor DSP is due to the reflected signal from the sea bottom, and the sea bottom signal detection flag k is set to the digital signal processor D.
Supply to SP. Digital signal processor D
The SP creates two-dimensional display data from the absolute value s, the current point in time, the deflection angle g, and the seabed signal detection flag signal k, and supplies the display data to the display unit DIS for display.

Let the envelope amplitude of the received signals a ₁ and a _{2 be} A
(T), the angular frequency of the carrier wave is ω, and the phase is φ ₁ , respectively.
If φ ₂ is set, a ₁ = A (t) cos (ωt + φ ₁ ) a ₂ = A (t) cos (ωt + φ ₂ ).

The received signal a ₁ is sent to the sampling circuit SPL.
1, the sampling is performed using the sampling signal sp _i and the sampling signal sp _q delayed by τ from the sampling signal sp _i by the delay circuit DLY. The sampled received signal p ₁ (t) by the sampled signal sp _i appearing at time t and the time t
= Sampled received signal q by the sampled signal appearing at t + τ
(T) _{is, p 1 (t) = A} (t) cos (ωt + φ 1) q 1 (t) = a 1 (t + τ) = A (t + τcos [ω (t + τ) + φ 1 ] ≒ A (t) cos [ ω (t + τ) + φ ₁ ]. Here, when τ is ωτ = π / 2, q ₁ (t) ≈A (t) cos [(ωt + φ ₁ ) + π / 2] = -A (t ) Sin (ωt + φ ₁ ).

In the complex signal synthesis circuit CMPX1, p
Complex number r _{1 where 1} (t) is the real part and q ₁ (t) is the imaginary part
Is synthesized. That is, the complex number r ₁ is r ₁ = p ₁ (t) -jq ₁ (t) = A (t) cos (ωt + φ ₁ ) + jA (t) sin (ωt + φ ₁ ) = A (t) exp [j ( ωt + φ ₁ )]. r ₁ is a complex number whose argument is the phase angle (ωt + φ ₁ ) of the received signal a ₁ .

Similarly, r ₂ = p ₂ (t) -jq ₂ (t) = A (t) cos (ωt + φ ₂ ) + jA (t) sin (ωt + φ ₂ ) = A (t) exp [j (ωt + φ _2). )] r ₂ is a complex number whose argument is the phase angle (ωt + φ ₂ ) of the received signal a ₂ .

Therefore, by the phase angle calculation unit ARG,
Complex number r₁And r₂Compute the complex conjugate product of
When calculated, the output g of ARG is g = Arg [r₁・ R₂ ^*] = Φ₁-Φ₂ = Δφ Becomes Thus, the received signal a₁, A₂Phase difference between
Is obtained, the azimuth angle θ of the fish seen from the transducer
_XTurns out.

The addition result of the addition circuit ADD is   h = r₁+ R₂     = A (t) [exp j (ωt + φ₁) + Exp j (ωt + φ₂)] Becomes

In the water bottom determination circuit BTM, the absolute value circuit AB
A certain threshold value (that is, the intensity equivalent to the reflection signal from the seabed) is set for the absolute value s calculated in S, and the absolute value s is compared with this threshold value, and only when the absolute value s is continuously large. , The absolute value s supplied to the digital signal processor DSP is judged to be the reflected signal received from the seabed,
The seabed signal detection flag k is output to the digital signal processor DSP. The digital signal processor DSP creates two-dimensional display data from the absolute value s, its output time, the deflection angle g and the seabed signal detection flag k, and supplies it to the display unit DIS for display.

FIG. 2 is an example of a multi-dimensional display screen in the ultrasonic survey apparatus of this embodiment. Description of the same reference numerals as those in FIG. 5 will be omitted. The t of the ship in the upper left of FIG.
The display screen a) of the -y cross section and the display screen b) of the xy cross section in the upper right of FIG. 2 have the same display as the screens a) and b) of FIG. However, the seabed signal detection flag k from the seabed determination circuit BTM indicates that the digital signal processor D
By being supplied to the SP, the seabed can be displayed in addition to the reflecting objects of c1 and c3 in the ty cross-sectional view at an arbitrary depth y1. Then, the reflection signal from the seabed and the reflection objects c1 and c3 can be displayed separately as in the display screen c) of the yy section in the lower left of FIG. In addition, the display color of the seabed may be displayed in a dark color so that the display color of the seabed and the display color of the reflective object do not overlap, or conversely, the display of the reflective object may be displayed in white.

By adding the seafloor depth information to the display in c) of FIG. 2, a tx sectional view at an arbitrary depth y1 is shown in FIG.
The seabed can be displayed in a color corresponding to the depth of the seabed as in d). Although not illustrated in the figure, if there is a reflecting object in the cross section at the depth y1, the display of this reflecting object can also be superimposed on FIG. 2d).

FIG. 3 shows another example of the multi-dimensional display screen in the ultrasonic survey apparatus of this embodiment. Description of the same reference numerals as those in FIG. 5 will be omitted. Z1 of the display screen a) of the ty cross section of the ship in the upper left of FIG. 3 is a mark indicating the seabed expansion range. FIG. 3a ′) is an example in which only the range of the mark z1 indicating the seabed expansion range shown in FIG. 3a) is displayed by enlarging the seabed. FIG. 3b ′) is an example in which only the range of the mark z1 indicating the seabed expansion range shown in FIG. 3b) is displayed by enlarging the seabed. Since it is possible to judge the bottom sediment quality from the change in the reflection intensity (color of the bottom image) from the bottom and the length of the tailing, the enlarged bottom view shown in these Figures 3a ') and 3b') shows even more It becomes easier to compare the reflection intensity, and it is possible to judge the bottom sediment quality.

[0031]

As described in detail above, the ultrasonic probe of the present invention detects the direction of a reflecting object in water from the phase difference of the received signals, and based on the intensity of the received signals,
Since it is a configuration that can distinguish the received signal of the reflection object and the bottom of the water, it is possible to accurately grasp the direction and position of the reflection object in the water, and by expanding the seabed, it becomes easier to judge the bottom quality of the bottom. , The effect of easily grasping the accurate underwater and bottom conditions can be achieved.

Further, the display screen of the xy cross section as shown in FIG. 3b) is enlarged on the seabed and displayed as shown in FIG. 3b ').
With the conventional fish finder, it is possible to display the enlarged seabed in the xy section, which was difficult.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of an ultrasonic probe according to an embodiment of the present invention.

FIG. 2 is an example of a multidimensional display screen by the ultrasonic survey apparatus of the embodiment of FIG.

FIG. 3 is an example of a multi-dimensional display screen including a display for expanding the seabed by the ultrasonic probe of the embodiment of FIG.

FIG. 4 is a conceptual diagram for explaining a principle of detecting an azimuth angle of a reflecting object based on a phase difference between two reception signals.

FIG. 5 is an example of a multi-dimensional display screen by a conventional ultrasonic probe.

[Explanation of symbols]

CNT control section TX transmission section IS1, IS2 single circuit TD1, TD2 ultrasonic transducer AMP1, AMP2 amplification circuit SPL1, SPL2 sampling circuit CMPX1, CMPX2 complex synthesis circuit ARG phase difference detection circuit ADD addition circuit ABS absolute value circuit BTM water bottom determination circuit DSP Digital signal processor DIS Display device DLY Delay circuit

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kazuhiro Moriguchi             7-2-6 Nagatsuda, Midori-ku, Yokohama-shi, Kanagawa (72) Inventor Kenji Miyajima             3-11-2 Myojincho, Hachioji City, Tokyo Court             Plaza Hachioji 206 (72) Inventor Naomi Matsuki             3-14-19 Sennincho, Hachioji City, Tokyo Hikari Heim             No. 403 F-term (reference) 5J083 AA02 AB01 AB06 AC29 AC32                       AD06 AD17 AE04 AE06 AF16                       BE17 BE38 CA01 CA12 EA28                       EA47

Claims (4)

[Claims] 1. A transmission section having a transmission element for transmitting an ultrasonic signal, and a reception section having a plurality of reception elements for receiving reflected waves of an object of the transmitted ultrasonic signal and outputting reception signals. An azimuth detecting unit that detects the azimuth of the object from the arrangement of the plurality of receiving elements and the phase difference of the received signals output from the respective receiving elements, and the distance and the reflection intensity of the object from the output current time and the amplitude of the received signal. An ultrasonic exploration device comprising: a distance / reflection intensity detection unit for detecting the object, and a display processing unit that displays the object on the screen using the detected azimuth, distance, and reflection intensity as display data. An ultrasonic probing apparatus comprising a water bottom determination unit that determines the water bottom based on the intensity of a reflection signal output from a reflection intensity detection unit. 2. The ultrasonic probing apparatus according to claim 1, wherein the display processing unit displays the reflection signal determined to be the water bottom by the water bottom determination unit in a specific color. 3. The ultrasonic probing apparatus according to claim 1, wherein the display processing unit displays the reflection signal determined to be the water bottom by the water bottom determination unit in a color corresponding to the depth of the water bottom. 4. The ultrasonic probing apparatus according to claim 1, wherein the display processing unit magnifies and displays the reflection signal determined to be the water bottom by the water bottom determination unit.