JPH04134292A - Embedded object locating process in underground ahead detection with shield method - Google Patents

Abstract

PURPOSE:To sense the location of any embedded object three-dimensionally with high precision by feeding the concentration values obtained from the reflexion intensity into each picture element of a two-dimensional image memory, and displaying as a three-dimensional image. CONSTITUTION:Two-dimensional image memories 16 having a plurality of picture elements storing concentration values in the direction to the left and right and in the vertical direction are installed fore and aft as corresponding to the natural ground ahead a shield excavating machine 11, and thus a three-dimensional image memory 17 is provided. It is assumed that there is embedded object 15 in every two-dimensional image memory 16, and the concentration values of the processing data position corresponding to the distance of picture element of each two-dimensional image memory 16 from a signal transmitter 13 and receiver 14 are fed to picture element of each two-dimensional image memory 16. By this processing, a rotational ellipse focusing at the transmitter 13 and receiver 14 appears in three-dimensional image at measurement for one place, and the concentration value of the picture element of a part overlapped with the ellipse from other measuring point will be heightened. This permits judgement that an embedded object 5 exists in the natural ground position corresponding to the picture element position where concentration value is high.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for determining the position of buried objects in the ground in front of a shield excavator when excavating an I-channel using the shield method.

Conventional technology Conventionally, forward exploration underground has been conducted, for example, in Japanese Patent Application Laid-open No.
Japanese Patent No. 3090 discloses a buried object detection method using a sound wave reflection method.

Problems to be Solved by the Invention However, the above-mentioned buried object detection method merely checks the presence or absence of underground objects, but it is difficult to accurately determine their position three-dimensionally. This is because accurate data with no variation is required to three-dimensionally detect a buried object using the sound wave reflection method, and it is difficult to obtain such data using the sound wave reflection method.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and provide a method for determining the position of a buried object in front of the Schild's method, which allows the position of the buried object to be obtained as a three-dimensional image with high precision.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention provides a transmitter that is installed in the cutter of a shield excavation machine and transmits sound waves into the ground in front, and a transmitter that transmits sound waves from the ground that is reflected from the ground. When determining the position of a buried object in front using a receiver that receives A three-dimensional image memory in which a plurality of two-dimensional image memories are arranged in the front and rear directions is set, and the two-dimensional image memory is equal to the distance between the transducer and the buried object obtained from the reflected wave arrival time of the received reflected wave data. A three-dimensional image is displayed by inputting the density value obtained from the reflection intensity of the reflected wave data into each pixel of The density values are added to each, and the position where the density values overlap and the density becomes high is determined as the location of the buried object.

Operation According to the above method, density values are input into pixels of a two-dimensional image memory equal to the distance between one transmitter and receiver and the buried object using the reflected wave data obtained from the - point, and a three-dimensional image is created. The density values of the reflected wave data obtained from multiple points are added to the pixels of each two-dimensional image memory, and the position where the density values overlap and the density becomes high is determined as the location of the buried object, so the sound wave reflection The position of buried objects can be determined dimensionally with high accuracy even when using the method.

Example An embodiment of the present invention will be described below based on the drawings.

As shown in FIG. 1, the cutter head 12 of the shield tunneling machine 11 is provided with transmitters 13 at predetermined intervals in the radial direction.
and a receiver I4 are respectively attached, and the transmitter 13 transmits sound waves into the underground ground at multiple positions where the cutter head 12 rotates, and the receiver 14 receives the reflected waves reflected from the buried object 15. be done.

This reflected wave data is transmitted to the transmitter 13 as shown in FIG.
The sum of the distance a between the buried object 15 and the distance between the buried object 15 and the receiver 14 is equal to the arrival time t of the reflected wave x the speed of sound in the soil f, and the intensity of the reflected wave is, for example, 0 to 1. expressed.

The processing of this reflected wave data will be explained in order below.

■Preprocessing of reflected wave data [Figure 3] The reflected wave data is processed as shown.

h is a density value and is determined by the intensity of the reflected wave, and W is determined in proportion to the distance by appropriately selecting the distance in the front-back direction (for example, the estimated length of the buried object 15).

■ Setting the grayscale image memory [Figure 4 (a), (b)
] Corresponding to the ground in front of the shield excavator 11, a two-dimensional image memory 16 is set as a three-dimensional image memory 17 in which a plurality of pixels are arranged in the front-rear direction and have a plurality of pixels that store density values in the left-right direction and the up-down direction. do. In other words, the three-dimensional image memory 17 is configured with a plurality of pixels in the horizontal direction, a plurality of pixels in the vertical direction, and a plurality of planes in the front-rear direction, and the ground is located in front of the cutter head 12 of the shield excavator 11 by a predetermined distance. A mountain space (range AX in the left-right direction, range B in the vertical direction x range C in the front-rear direction) is assigned to the three-dimensional image memory 17.

■Concentration distribution [Fig. 5 (a), (b)), (Fig. 6) Distance a1 between the transmitter 13 and the position 18 where concentration values are distributed, and distance a1 between the receiver 14 and the position 18 where the concentration values are distributed. Calculate the distance b1 of
, Y, and Z are the coordinates of the position 18 where the concentration values are distributed. Next, as shown in FIG. 6, a, +b are the transmitter 1
The density value h1 corresponding to the distance al+bl is input to each pixel of the two-dimensional image memory 16 corresponding to the distance a++b. [Actually, considering that there is a buried object 15 for every two-dimensional image memory 16,
Pixels of each two-dimensional image memory 16 and transmitter 13. The density value of the processed data position corresponding to the distance from the receiver 14 is input into each pixel of the two-dimensional image memory 16. For example, in Fig. 6, h is input to all pixels corresponding to a++b: (pixels located on the ellipsoid surface with the emitter 13 and receiver 14 as focal points), and the distance is shorter or longer than al + bl. For the pixel, a density value of 0 is manually input. ] As described above, the above processing is performed for each measurement at one location.

The above measurements are performed at a plurality of locations during one rotation of the cutter head 12, and each processed data is added to each pixel of the two-dimensional image memory 16. (The density values are added.) Here, the maximum value of the density values input to each pixel is determined by taking into account the storage capacity of the memory. For example, when adding up all the maximum density values of each measurement point, However, it is set to a value that does not overflow.

As a result of the above processing, as shown in Fig. 7, a spheroid with the transmitter 13δ and receiver 14 as focal points appears in the three-dimensional image when measuring one location, and an ellipsoid (with a book and a book) from other measurement locations appears. The density value of the pixel in the overlapping part becomes high.From this (2), it is determined that the buried object 15 exists at the position of the ground corresponding to the pixel position with the high density value.

By providing the cutter head 12 with a plurality of receivers 14 or a plurality of transmitters 13 and receivers 1.1, it is possible to measure a plurality of points even at the same rotation angle position of the cutter head 12.

Next, the above specific example will be explained with reference to FIGS. 8 to 13.

FIG. 8 shows the configuration of the buried object detection device. The transmitter 13 and the receiver 14 are connected to a forward search device 19, and the signal from the forward search device 19 is processed by a position determination device 20 according to the invention and displayed on an image display device 21.

Examples of the image display will be explained with reference to FIGS. 9 to 11. Figure 9 is a cross-sectional image at an arbitrary distance E in the forward and backward direction, and the cross section and force at an arbitrary distance E in the traveling direction.
2 is displayed, and the direction of the buried object 15 is estimated. FIG. 10 is a longitudinal cross-sectional image at an arbitrary distance F in the left-right direction, the cross-section at an arbitrary distance F in the width direction and the distance from the center of the shield excavator 11 are displayed, and the distance to the buried object 15 is estimated. FIG. 1I shows a binarized image, in which the grayscale image obtained above is binarized using an arbitrary density threshold. The threshold value can be changed continuously, and only the locations where the buried object 15 is likely to exist are displayed. Furthermore, if the density areas are displayed in different colors, the possibility of the existence of the buried object 15 can be determined by the color.

A specific example of distance calculation will be explained with reference to FIGS. 12 and 13.

Here, the two-dimensional image memory 16, which has 128 pixels in the horizontal direction A and 108 pixels in the vertical direction B, is
Configure by arranging 0 sides. If the center O of the shield tunneling machine 12 is the origin, the coordinates of the transmitter 13 are (r + sin θ,
rlcO5θ, 0), the coordinates of the receiver 14 are (r 2si
nθ, r2cO3θ, 0) The coordinates of the Oth pixel on the Oth surface are the coordinates Direction) 1 pixel width (X direction) 1 pixel width (Z direction) / A-th screen, m-th pixel in the X direction.

The mark is the coordinate x =-: A/2-A/(128X2)-m XA
/128] Coordinate y=B/2-B/(]08X2)
-n XB/'108 coordinate z = D +C/ ('
, 20X2)+l Assuming that the rotation color amount is 〇, the distance from the transmitter 13 to the high density value distribution position 18: a2'' (, r+slnθ
-x + (,r+CO3θ-Y)2+Z2 Distance from receiver 14 to high concentration value distribution position 18 (l 28\2)] ('108X2) 0 × 2) A '128 B, 108 C/ 20 y direction Dislocation of n-th pixel: b:= (r2sinθ−x)”(r
2 cos θ-v) 2-1'' Distances a, +b are added to each pixel of the two-dimensional image memory 16 corresponding to this distance a2+b2.
The density value h2 corresponding to , , is manually generated.

Effects of the Invention As described above, according to the present invention, the reflected wave data obtained from the - point is used to generate reflected waves at each pixel of the two-dimensional image memory equal to the distance between the transmitter, the receiver, and the buried object. The density values obtained from the intensity are input and displayed as a three-dimensional image, and the density values of reflected wave data obtained from multiple points are added to the pixels of each two-dimensional image memory, and the density values are overlapped and displayed as a three-dimensional image. Since the elevated position is defined as the location of the buried object, the position of the buried object can be detected three-dimensionally with high accuracy even if the sound wave reflection method is used.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, and FIGS. 1 to 3 are explanatory diagrams showing preprocessing of reflected wave data, and FIGS. 4(a) and 4(b) are explanatory diagrams of a three-dimensional image memory, respectively. Figure 5 (a) (
b), Fig. 6 is an explanatory diagram showing distance calculation and concentration assignment, Fig. 7 is an explanatory diagram of concentration distribution, Fig. 8 is a schematic configuration diagram of the buried object detection device, and Fig. 9 (a) (b) - Figure 11(a)
(b) is an explanatory diagram showing an example of image display, FIG.
FIG. 13 is an explanatory diagram of each coordinate calculation. 11... Shield excavator, 12... Cutter head, 13... Transmitter, 14... Receiver, 15... Buried object, I6゛... Two-dimensional image memory 17... Three-dimensional Image memory 18... High density distribution position, 19...
・Forward exploration device, 20...Positioning device, 21...
Image display device.

Claims (1)

[Claims] 1. Determine the position of the buried object in front using a transmitter installed on the cutter head of the shield excavator that sends out sound waves into the ground ahead, and a receiver that receives reflected waves from other mountains. In response to the other mountain in front of the shield excavator,
A three-dimensional image memory is set in which two-dimensional image memories each having a plurality of pixels that store density values in the horizontal and vertical directions are arranged on multiple sides in the front-rear direction. The density value obtained from the reflection intensity of the reflected wave data is input into each pixel of the two-dimensional image memory, which is equal to the distance between the transducer and the buried object, to display a three-dimensional image, and the series of detections described above is performed. Underground in the shield construction method, which is characterized by performing processing at multiple locations and adding density values to the same two-dimensional image memory, and determining the position where the density values overlap and the density is high as the location of the buried object. A buried object location determination method for forward exploration.