JP4871163B2 - Surveying system for excavator - Google Patents

Description

  The present invention relates to a system for surveying the excavation position and direction of an excavator in the ground.

  When constructing tunnels, urban sewers, gas pipes, power and communication cable pipes, joint grooves, etc. using shield construction, etc., the underground excavator can be used to minimize the construction deviation from the planned route. It is necessary to always survey the excavation position and direction.

Conventionally, as a technique for surveying the excavation position and direction of a shield machine that is excavating in the ground, as a calculation value from the measurement data by the bearing measuring instrument and the pitching measuring instrument and the measurement data by the shield jack stroke measuring instrument It is known to perform direction control during excavation based on the obtained displacement data (see, for example, the following patent document).
JP-A-5-321577

  However, the survey data of the shield machine based on the calculated values as described above is obtained by stopping the shield machine after excavating for a predetermined distance (for example, about 10 m) and performing optical surveying using the light wave rangefinder. There was a difference with the survey data obtained.

  The present invention has been made in view of the above-described problems, and a technical problem thereof is to make it possible to measure the position and direction of the excavator during excavation with higher accuracy.

As a means for effectively solving the above technical problem, a surveying system for an excavator according to the invention of claim 1 includes targets provided in a plurality of locations in the excavator, and existing tunnels behind the excavator. A camera that is installed at a predetermined location and shoots the inside of the excavator together with the target and outputs an image signal, an excavation distance measuring unit that measures an excavation distance of the excavator, and processing the image signal. An image processing means for extracting an image and detecting its position coordinates; an initial value of the position coordinates of the target image; and a target interval P _m obtained from the digging distance measured by the digging distance measuring means at an arbitrary time point; following formula based on the interval P _n of the detected target image in the image processing means is captured by the camera at the arbitrary time point (1 And processing means for determining the deflection angle θ of the excavator by, is made of.

  That is, according to the above configuration, first, targets are provided in advance at a plurality of locations in the excavator, and a camera is installed at a predetermined location in the existing tunnel behind the excavator, and the interior of the excavator is photographed together with the target. The image signal from the camera is subjected to image processing by an image processing means, and the position coordinates of the target in this image are detected and set as an initial value.

Next, at a predetermined timing after the underground excavation by the excavator is started, the excavation distance of the excavator is measured by an excavation distance measuring unit, and the inside of the excavator is photographed with the target by a camera. The distance P _n between the target images detected by performing image processing on the image at this time is a coordinate obtained from the digging distance measured by the digging distance measuring means and the initial value of the target position coordinate obtained in advance. If it is equal to the interval P _m, it can be understood that the excavator is traveling straight, and if P _n <P _m , it can be understood that the excavation direction has changed. The angle θ can be obtained.

  A surveying system for an excavator according to a second aspect of the present invention is the survey system according to the first aspect, wherein the target has a specific brightness or color tone, and the position coordinates of the target in the captured image data are obtained by image processing. It is obtained by extracting a specific luminance or tone from the data.

  A surveying system for an excavator according to a third aspect of the present invention is the surveying system according to the first aspect, wherein a plurality of targets are respectively installed in a substantially horizontal direction and a substantially vertical direction. If it does in this way, the change of the excavation direction to the horizontal direction and the elevation direction of an excavator can be detected.

  A surveying system for an excavator according to a fourth aspect of the present invention is the survey system according to the first aspect, wherein the target is selected from any part or part in the excavator. That is, the target is a fixed object that can be photographed by the camera and has a color or brightness that can be easily extracted by performing image processing on the image signal from the camera. Any part or part in the excavator can be substituted.

  A surveying system for an excavator according to a fifth aspect of the present invention is the survey system according to the first aspect, wherein the excavation distance measuring means comprises a stroke sensor for measuring a stroke length of a jack for propelling the excavator.

  The surveying system for an excavator according to a sixth aspect of the present invention is the survey system according to the first aspect, wherein the arithmetic processing means is configured to detect a difference in the image area of each target extracted by image processing or an initial value of the image area of each target The deflection direction of the excavator can be determined based on the difference in the area change rate.

  The surveying system for an excavator according to a seventh aspect of the present invention is the survey system according to the first aspect, wherein the arithmetic processing means is configured to calculate an interval between arbitrary targets extracted by image processing and an interval between other arbitrary targets. By comparing the ratio with its initial value, the deflection direction of the excavator can be determined.

The surveying system for an excavator according to the invention of claim 8 is the surveying system according to claim 1, wherein the arithmetic processing means includes the coordinates of the planned position of the reference point of the excavator on the image and the reference point of the taken excavator. the distance L ₂ between the coordinates, and the excavation direction at the planning position, from the direction of the optical axis of the camera through the planning position is obtained by enabling calculates the shift amount Q of the shield machine for the planned route. In this way, in addition to the excavation distance and the excavation direction of the excavator, the deviation amount of the excavator with respect to the planned route can be measured, so that the excavator can be controlled with higher accuracy.

  According to the surveying system of the excavator according to the invention of claims 1 to 6, in the excavation process of the excavator, the measurement of the excavation distance and the shooting in the excavator including the target are performed in synchronization at an arbitrary timing. Based on the difference between the target interval on the image of the target and the target position coordinate interval obtained from the measured value of the excavation distance and the initial position coordinate of the target on the image, the excavation direction of the excavator can be determined with high accuracy. Therefore, the operation of the excavator can be controlled with high accuracy and the deviation of construction from the planned route can be minimized.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of a surveying system for an excavator according to the present invention will be described with reference to the drawings. FIG. 1 is an explanatory diagram showing a relationship between a shield machine, a target, and a digital camera in the survey system for an excavator according to the present invention, FIG. 2 is an arrangement diagram of the target viewed from the II direction in FIG. 1, and FIG. It is explanatory drawing which shows schematic structure of the surveying system of the excavation machine which concerns on this invention.

  First, in FIG. 1, reference numeral 1 is a shield machine used for tunnel construction by a shield method. This shield machine 1 includes a shield composed of a cylindrical front steel shell 111 and a cylindrical rear steel shell 112 connected to the rear thereof via an unillustrated hydraulic jack for unfolding. A cutter face 12 having a frame 11, a cutter face 12 having a number of cutter bits provided at the front end thereof for excavating natural ground, a cutter motor 13 including a hydraulic motor for rotating the cutter face 12, and the like. The lining segment 21 is sequentially assembled into a cylindrical shape in a chamber 14 formed on the back surface, into which excavated earth and sand (slipping) is taken in, a discharge pipe 15 for discharging the excavated earth and sand from the chamber 14, and a rear steel shell 112. A large number of erectors (not shown) for constructing the lining body 2 and the circumferential direction are arranged so as to push the tip of the existing lining body 2 backward. A plurality of arc-shaped primary lining segments 21 are assembled in an annular shape by an erector (not shown) on the inner periphery of the rear steel shell 112 of the shield frame 11 and the propulsion hydraulic jack 16 that obtains thrust in the direction of excavation. An unillustrated erector for constructing the lining body 2 to withstand the earth pressure of the natural ground G and the shield digging machine 1 by the reaction force by pressing the tip of the already-assembled lining body 2 backward And a propulsion hydraulic jack 16 to be propelled.

  The surveying system for the excavator according to this embodiment includes a plurality of targets 31 installed on the inner periphery of the rear part of the shield excavator 1 and a predetermined location on the inner periphery of the existing lining body 2. And a digital camera 32 that images the inside of the machine 1 together with the target 31.

  As the target 31, for example, a circular target made of a light emitting diode that emits red light is employed. The digital camera 32 corresponds to the camera described in claim 1 and outputs a captured image as an image signal of at least three colors of R, G, and B by a solid-state imaging device such as a CCD.

  Further, as shown in FIG. 3, the surveying system of the excavator according to this embodiment processes each image signal from the stroke sensor 33 and the digital camera 32 to identify the red color tone, thereby identifying each target 31. The image processing unit 34 that extracts the image of the image and detects the coordinates thereof, and the application program for executing the processing by the present system, the interval between the images of the target 31 and the image area of each target 31 are determined. There are various data such as an arithmetic processing unit 35 for performing various arithmetic processes such as obtaining from the number of pixels and obtaining the deflection angle of the excavator, data of the arithmetic processing result by the arithmetic processing unit 35, and the application program. The memory 36 to be stored, and a monitor display for outputting and displaying the image and the data of the arithmetic processing result by the arithmetic processing unit 35 Comprising a device and an output display unit 37 such as a printer. Among these, the image processing unit 34, the arithmetic processing unit 35, the memory 36, and the like are configured as a personal computer. The existing lining body 2 corresponds to the existing tunnel described in claim 1.

  The stroke sensor 33 is mounted on the propulsion hydraulic jack 16 and measures the digging distance of the digging machine 1 by measuring the length of the expansion / contraction stroke, and corresponds to the digging distance measuring means according to claim 1. To do.

  The image processing unit 34 processes the image signal from the digital camera 32 and extracts an image of each target 31 by identifying an R image signal in a specific layer.

  In surveying by the surveying system of the excavator configured as described above, the target 31 is first fixed in advance at a plurality of locations on the inner periphery of the rear portion of the excavator 1. In detail, as shown in FIG. 2, for example, each pair and four targets 31 (31R, 31L, 31T, 31B) in a substantially vertical direction and a substantially horizontal direction (left-right direction) form a cross with each other, that is, For example, a clock face is fixed at 12 o'clock, 3 o'clock, 6 o'clock and 9 o'clock through appropriate fixing means.

  On the other hand, the digital camera 32 is installed at a known predetermined location on the inner periphery of the existing lining body 2 so that the optical axis is directed forward (to the shield machine 1 side) so that all the targets 31 are in the field of view. The inside of the excavator 1 is photographed with the target 31 (31R, 31L, 31T, 31B).

  4 is an explanatory view schematically showing an initial image taken inside the excavator 1 together with the target 31 by the digital camera 32, and FIG. 5 is an explanatory view schematically showing an image taken at a predetermined timing after the start of excavation. FIG. 6 is an explanatory diagram showing the calculation principle of the deflection angle of the excavator.

  As shown in FIG. 4, the image data photographed by the digital camera 32 is composed of, for example, 3000 pixels in the X direction and the Y direction, that is, 9 million pixels, respectively. The image data is subjected to image processing by the image processing unit 34, and the image of each target 31R, 31L, 31T, 31B is extracted by identifying the red color tone (R signal).

である。そしてこれらのデータは、初期値としてメモリ３６に蓄積される。 Here, in the initial image data shown in FIG. 4, for example, the center position coordinates of the right target 31R are (X ₁ , Y ₁ ) and the center position coordinates of the left target 31L are (X ₂ , Y ₂ ). The interval P ₀ between the center position coordinates of both targets 31R and 31L is:

It is. These data are stored in the memory 36 as initial values.

  Next, underground excavation by the shield machine 1 is started. In this excavation, the ground face G is excavated by rotating the cutter face 12 at the front end of the front steel shell 111 of the shield frame 11, and the generated excavated earth and sand (also referred to as shear) is formed on the cutter face 12. The slit 14 is taken into the chamber 14 on the back surface thereof, and muddy water or the like is pressurized and supplied to the chamber 14 through a water supply pipe (not shown), whereby the back pressure of the cutter face 12 is changed to the ground water pressure of the natural ground G. While maintaining the pressurized state to be balanced and preventing the mud of the front surface from being ejected, the soil is continuously discharged through the soil discharge pipe 15 as the excavated soil is taken in.

  On the other hand, at the inner periphery of the rear steel shell 112 of the shield frame 11, a plurality of arc-shaped primary lining segments 21 are assembled in an annular shape by an unillustrated erector, and the earth pressure of the natural ground G is formed on the excavated pit inner wall. In addition to constructing the lining body 2 to withstand the above, the hydraulic jack 16 for propulsion is applied to the tip of the existing lining body 2 that has already been assembled and pressed backwards, and the shield machine 1 is applied to the above by the reaction force. The cutter face 12 is excavated while being excavated.

  When underground excavation by the shield machine 1 is started, photographing by the digital camera 32 and measurement of the excavation distance by measuring the stroke length of the hydraulic jack 16 for propulsion by the stroke sensor 33 are synchronized every predetermined time. Done. As the excavation progresses, the shield machine 1 and the target 31 attached thereto move away from the installation position of the digital camera 32. Therefore, the image data taken after the excavation starts is the initial image data shown in FIG. In comparison, the imaging of the shield machine 1 and the target 31 becomes smaller in inverse proportion to the digging distance.

である。 Here, as shown in FIG. 5, in the image data photographed at a predetermined timing after the start of excavation, for example, the center position coordinate of the right target 31R is (X ₁₁ , Y ₁₁ ), and the center of the left target 31L Assuming that the position coordinates are (X ₁₂ , Y ₁₂ ), in this case, the interval P _n between the center position coordinates of both targets 31R and 31L is:

It is.

If the shield machine 1 is traveling straight, the magnitude of P _n is determined by the distance L from the initial position measured by the stroke sensor 33 and the targets 31R and 31L in the initial image data shown in FIG. Should be equal to the distance P _m between the center position coordinates of both targets 31R and 31L, as determined by the distance P ₀ between the center position coordinates, and if the excavation direction changes as shown in FIG. , P _n <P _m . And the deflection angle (theta) of the shield machine 1 in that case is calculated | required by following Formula (1).

  The image area of each target 31 extracted by image processing is obtained by counting the number of pixels. When the digital camera 32 is installed at a position that is equidistant from each target 31, the image areas of the targets 31 in the initial image shown in FIG. 4 are equal to each other, and then the shield machine 1 goes straight ahead. 5, the image areas of the targets 31 in the image after the start of excavation shown in FIG. 5 are also equal to each other, but if the excavation direction is changed, the image areas of the targets 31 are different from each other. Specifically, as shown in FIG. 6, if the shield machine 1 is deflected to the right, the image area of the right target 31R is larger than the image area of the left target 31L.

  Therefore, the arithmetic processing unit 35 can determine the deflection direction of the shield machine 1 by comparing the image areas obtained from the number of pixels captured by each target 31.

  In contrast, when the digital camera 32 is not installed at a position that is equidistant from each target 31 in particular, the image area of each target 31 in the initial image shown in FIG. The image area of each target 31 is registered in the memory 36 as an initial value. After that, when the shield machine 1 goes straight, the image area of each target 31 in the image after the start of excavation shown in FIG. 5 has the same rate of change relative to the initial value, but if the excavation direction changes The image area of each target 31 has a different rate of change from the initial value. Specifically, as shown in FIG. 6, if the shield machine 1 is deflected to the right, the rate of change relative to the initial value of the image area is greater for the left target 31L than for the right target 31R. .

  Therefore, the arithmetic processing unit 35 can determine the deflection direction of the shield machine 1 by comparing the rate of change of the image area obtained from the number of pixels captured by each target 31.

  In the above description, only the left and right deflection of the shield machine 1 is mentioned, but the vertical deflection direction and the deflection angle are also described from the upper target 31T and the lower target 31B. It is obtained in the same way as

  Moreover, although the above-mentioned description presupposes a straight tunnel, this invention can be implemented also to construction of a curved tunnel.

  In this case, first, the absolute position (X, Y, Z) of the digital camera 32 and the absolute shooting direction ( eX, eY, eZ) are calculated and set as initial values. Next, when the digital camera 32 is fixed, the position coordinates of the target 31 or a part of the shield machine 1 on the image are simulated as planned positions for each propulsion position of the shield machine 1. Then, the actual excavation position of the shield machine 1 can be calculated by comparing the simulation result with an actual image.

FIG. 7 is an explanatory diagram showing the calculation principle of the deviation amount of the shield machine 1 with respect to the planned route of the curved tunnel. In FIG. 7, a curve A is a design movement trajectory (hereinafter simply referred to as a planned route) of the reference line of the tunnel planned route, that is, the reference point of the shield machine 1 (for example, the center point of the rear end of the shield frame 11). ), and shift amount Q of the shield machine 1 from the planned route a corresponds to the length of a perpendicular line L ₁ drawn toward the reference point O ₁ of the shield machine 1 to the planned route a, this perpendicular line An intersection O ₂ between L ₁ and the planned route A is a planned position where the reference point O ₁ of the shield machine 1 should originally exist. Further, on the image by the digital camera 32, the shift amount Q is, as shown in FIG. 5 described above, the coordinates (X ₂₁ , Y ₂₁ ) of the reference point O ₁ of the shield machine 1 and the planned position O _2. And expressed as a distance L ₂ between the coordinates (X ₂₂ , Y ₂₂ ). The inter-coordinate distance L ₂ is obtained in the same manner as P ₀ or P _n described above from the coordinates (X ₂₁ , Y ₂₁ ) and (X ₂₂ , Y ₂₂ ).

Then, as shown in FIG. 7, the excavation direction of the shield machine 1 in plan position O _2, the direction of the optical axis V of the digital camera 32 through the planned position O ₂ of the shield machine 1, the perpendicular L ₁ Since the angle α with the optical axis V is known, the shift amount Q can be obtained by the following equation (2).

  Further, the calculation processing unit 35 can output the calculation result to the jack drive control unit 38, and can control the driving of the propulsion hydraulic jack 16 shown in FIG. 1 via the jack drive control unit 38. That is, the stroke amount of each propulsion hydraulic jack 16 for correcting the excavation direction is calculated from the deflection direction, deflection angle θ, and deviation amount Q of the shield machine 1 obtained as described above, and its control value is calculated. Is output to the jack drive control unit 38, the excavation direction can be controlled in real time, and the construction deviation from the planned route can be minimized.

  The target 31 does not necessarily have to be a dedicated member made of a red light emitting diode as described above. If the target 31 is a fixed object that can be photographed with a digital camera and can be easily extracted by image processing, the target 31 is shielded. Any part in the excavator 1 may be colored, or a part having a specific color or brightness may be used as a target.

  8 is an explanatory diagram schematically showing an initial image when the target is arranged differently from FIG. 2, and FIG. 9 is an explanatory diagram schematically showing an image taken at a predetermined timing after the start of excavation. FIG.

That is, the target 31 is not limited to the arrangement example as shown in FIG. 2, and as shown in FIG. 8, for example, the target 31 may be arranged so as to be positioned at each vertex of a substantially horizontal square (or rectangle). . Also in this case, the calculation interval P _m obtained from the interval P ₀ between the center position coordinates of the target 31 in the initial image shown in FIG. 8 and the excavation distance L from the initial position measured by the stroke sensor 33, From the interval P _n (P _nR , P _nL , P _nT , or P _nB ) between the center position coordinates of the target 31 in the image taken at the predetermined timing after the start of excavation shown in FIG. The deflection angle θ of the shield machine 1 can be obtained from Equation (1).

In addition, in the image taken at a predetermined timing after the start of excavation shown in FIG. 9, the distance P _n between the center position coordinates of the upper right target 31RU, the upper left target 31LU, the lower right target 31RL, and the lower left target 31LL. The ratio of P _nR , P _nL , P _nT , P _nB ) is equal to the ratio in the initial image when the shield machine 1 goes straight from the initial position, but if the direction of excavation changes, The ratio changes. Specifically, for example, if the shield machine 1 is deflected to the right, as shown in FIG. 9, the interval P _nR between the center position coordinates of the upper right target 31RU and the lower right target 31RL is It becomes relatively larger than the distance P _nL between the center position coordinates of the target 31LU and the lower left target 31LL. Similarly, when the shield machine 1 is vertically deflected, the interval P _nT between the center position coordinates of the upper right target 31RU and the upper left target 31LU and the center position of the lower right target 31RL and the lower left target 31LL. The ratio with the interval P _nB between the coordinates changes.

  Therefore, the arithmetic processing unit 35 can determine the deflection direction of the shield machine 1 by comparing the interval between the center position coordinates of the imaging of each target 31. In this case, since it is not necessary to obtain the image area of the target 31, the target 31 may be relatively small.

It is explanatory drawing which shows the relationship between the shield machine, a target, and a digital camera in the preferable form of the survey system of the machine which concerns on this invention. FIG. 2 is a layout view of targets as viewed from the II direction in FIG. 1. It is schematic structure explanatory drawing which shows the preferable form of the surveying system of the excavation machine which concerns on this invention. It is explanatory drawing which shows an initial stage image roughly. It is explanatory drawing which shows roughly the image image | photographed at the predetermined timing after the start of excavation. It is explanatory drawing which shows the calculation principle of the deflection angle of an excavation machine. It is explanatory drawing which shows the calculation principle of the deviation | shift amount of an excavation machine with respect to a planned route. It is explanatory drawing which shows roughly the initial image at the time of setting a target different from FIG. It is explanatory drawing which shows roughly the image image | photographed at the predetermined timing after the start of excavation when a target is arranged differently from FIG.

Explanation of symbols

1 Shield machine 16 Hydraulic jack for propulsion 2 Covering body (existing tunnel)
31 (31R, 31L, 31T, 31B) Target 32 Digital camera (camera)
33 Stroke sensor (digging distance measuring means)
34 Image processor 35 Arithmetic processor

Claims (8)

Targets provided at a plurality of locations in the excavator, a camera installed at a predetermined location in an existing tunnel behind the excavator and photographing the interior of the excavator together with the target and outputting an image signal, and excavation of the excavator An excavation distance measuring means for measuring a distance; an image processing means for extracting an image of the target by processing the image signal; and detecting a position coordinate thereof; an initial value of the position coordinate of the target image and an arbitrary time point Next, based on the target image interval P _m obtained from the excavation distance measured by the excavation distance measuring means and the target image interval P _n photographed by the camera at the arbitrary time point and detected by the image processing means, A surveying system for an excavator characterized by comprising: an arithmetic processing means for obtaining a deflection angle θ of the excavator by a formula .

  The target has a specific luminance or color tone, and the position coordinates of the target in captured image data are obtained by extracting the specific luminance or color tone from the image data by image processing. The surveying system for the excavator according to 1.   The survey system for an excavator according to claim 1, wherein a plurality of targets are installed in each of a substantially horizontal direction and a substantially vertical direction.   2. The surveying system for an excavator according to claim 1, wherein the target is selected from any part or part in the excavator.   The surveying system for an excavator according to claim 1, wherein the excavation distance measuring means comprises a stroke sensor for measuring a stroke length of a jack for propelling the excavator.   The arithmetic processing means can determine the deflection direction of the excavator based on the difference in image area of each target extracted by image processing or the difference in area change rate with respect to the initial value of the image area of each target. The surveying system for an excavator according to claim 1, wherein   The arithmetic processing means can determine the deflection direction of the excavator by comparing the ratio between the interval between arbitrary targets extracted by image processing and the interval between other arbitrary targets with its initial value. The surveying system for an excavator according to claim 1, wherein the surveying system is provided. Arithmetic processing means, and the distance L ₂ between the coordinates of the excavator reference point plan coordinates and photographed excavator reference point in on the image, the excavation direction at the planning position, the planned location The surveying system for an excavator according to claim 1, wherein a deviation amount Q of the excavator with respect to the planned route can be calculated from the direction of the optical axis of the camera passing through.

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