JP4230400B2 - Drilling tip position measurement system in borehole depth drilling and measurement method using the same - Google Patents

Description

  The present invention relates to an excavation tip position measurement system and a measurement method using the excavation tip position excavation in a borehole depth excavation such as soil improvement.

  Conventionally, as a prior art in such a field, for example, there is one as shown in FIG. That is, there is a measuring device 103 suspended by a cable 102 via a pulley 106 in the measuring tube 101, and the measuring device 103 has a hole core measuring instrument 104 and a measuring tube for measuring pitching, yawing and rolling by a three-axis mechanical gyro. A gap sensor 105 that monitors the positional relationship between the 101 inner diameter and the measuring device 103 is provided.

In addition, as an automatic surveying system in the propulsion method, an instrument that measures the bending of a tube using an optical laser as a measuring instrument is disclosed (Patent Document 1 below).
JP 2002-48543 A

  However, in the measurement system equipped with the gyro and the gap sensor shown in FIG. 9, the accumulated error of the gyro is large, and the measurement accuracy by the gap sensor is also difficult. In addition, it is necessary to pay attention to the handling of the measuring device itself having a length of 2 m.

  In view of the above situation, an object of the present invention is to provide an excavation tip position measurement system and a measurement method thereof in deep hole excavation that is easy to handle and has good measurement accuracy.

In order to achieve the above object, the present invention provides
[1] In an excavation tip position measurement system in borehole depth excavation, a plurality of pipes are connected, a pipe having a magnetic marker in the vicinity of a joint portion of each pipe, and set along the inside of the pipe. A link having a length substantially equal to the length of the tube, a tilt sensor disposed on a tilt base provided at an upper end of the link and perpendicular to the link, and a position where the magnetic marker is disposed. A measurement unit having a magnetic sensor that can circulate around the inner wall of the pipe and a target unit that is arranged at the lower end of the link are mounted on the measurement unit as the suspension wire connected to the measurement unit is pulled up or down. The position of the target unit is sequentially measured based on information from the tilt sensor and the magnetic sensor.

  [2] In the excavation tip position measurement system in the borehole depth excavation described in [1] above, the inclination angle of the link with respect to the gravitational acceleration direction when the link is passed to two points of the pipe center by the inclination sensor, and the magnetic The target unit position is measured based on the azimuth coordinates from the link angle obtained by measuring the deflection angle of the magnetic markers arranged in two adjacent tubes with a sensor.

  [3] In the excavation tip position measurement method in borehole depth excavation, using the excavation tip position measurement system in borehole depth excavation described in [1] or [2] above, (a) an elevating unit and an upper end jig of a pipe A step of setting an upper portion of the pipe and giving an initial value of the azimuth by inserting a measuring device; (b) a step of releasing the brake until the lower end of the pipe is detected; and (c) starting from the lower end of the pipe. A step of raising the brake to the first pipe joint position at low speed, and (d) when the pipe joint part is reached, the lock mechanism of the measuring unit is locked in the groove, and the magnetic sensor is locked at this position. The step of reading and recording the magnetic marker position of the pipe and the tilt angle by the tilt sensor, (e) releasing the brake and ascending to the next pipe joint, (f) moving The brake is in an operating state at a reduced level, the step of moving until the wheels of the measuring unit are locked, and (g) the above steps (d) to (f) are repeated until reaching the upper end jig of the pipe. And performing the process.

  [4] Using the excavation tip position measurement system in the borehole depth excavation described in [1] or [2] above, (a) setting the lifting unit and the upper end jig of the pipe on the upper part of the pipe, and inserting the measuring device A step of giving an initial value of the azimuth, (b) a step of lowering the measurement unit until the lower end of the pipe is detected, and (c) a hoisting wire is wound up by a constant amount from the lower end of the pipe, In the measurement unit, the magnetic marker position of the tube by the magnetic sensor and the inclination angle by the inclination sensor are read and recorded, and (d) step (c) is repeated until the upper end jig of the tube is reached. And a step of performing a drilling tip position measuring method in a borehole depth excavation.

  [5] In the excavation tip position measurement method in the borehole depth excavation described in [3] or [4] above, a step of stopping the measurement when the measurement device reaches the upper end, and downloading of measurement data from the data processing device on the ground side According to the command, the measurement data is downloaded, and the position is calculated by the data processing device.

  According to the present invention, it is possible to provide an excavation tip position measurement system and a measurement method using the excavation tip depth excavation that are easy to handle and have good measurement accuracy.

  A pipe having a magnetic marker arranged in the vicinity of a connection portion of each pipe, and a link having a length substantially equal to the length of each pipe set along the inside of the pipe. And a measurement unit having an inclination sensor arranged on the upper end surface perpendicular to the link and a magnetic sensor capable of circling the circumference of the position where the magnetic marker is arranged. And a target unit disposed at the lower end of the link, and sequentially measure the target unit position geometrically. Since it does not have a fragile gyro sensor, it is easy to handle and has good measurement accuracy even in a poor environment.

  Hereinafter, embodiments of the present invention will be described in detail.

  First, the measurement principle of the excavation tip position in the borehole depth excavation of the present invention will be described.

  FIG. 1 is an explanatory diagram of the principle of measurement of the drilling tip position in the borehole depth drilling of the present invention.

  In this figure, first, the position of the link tip 1A is obtained from the inclination angle φ of the link 1 with respect to the gravitational acceleration direction g when the link 1 having a fixed length l (1.5 m) is passed to two points at the center of the tube. The inclination angle in each axial direction with respect to the vertical axis of the link is obtained as an inclination angle as an inclination angle with respect to the horizontal plane of an inclination table attached perpendicularly to the link. However, since the inclination angle obtained at this time is relative to the reference axis of the measuring device A, the accurate tip position cannot be measured unless the declination angle with respect to the azimuth coordinates of the measuring device A is known. For this reason, magnetic markers 14 and 15 in which magnets are embedded are arranged in the vicinity of the joint portions 11A and 12A of the pipes 11 to 13, and are mounted on the target unit 3 and the measurement unit 4 of the measuring device A, respectively (see FIG. 1). The declination angle between the magnetic markers 14 and 15 arranged on the two adjacent tubes 11 and 12 is measured by the arrow portion), and the azimuth coordinates are calculated from this and the inclination angle ψ of the link 1.

  Here, if the interval between the magnetic sensors arranged in the target unit 3 and the measurement unit 4 and the length 1 of the link 1 are made to coincide with the fixed length of the pipes 11 and 12, the pipe joint parts 11A, The positions of the magnetic markers 14 and 15 can be measured at intervals of 12A. Since the measurement unit 4 measures the same magnetic marker as measured by the target unit 3 at the next measurement position, the rotation of the entire measurement unit 4 can be known from the two angle differences.

  Therefore, if the rotation angle and coordinates of the measurement unit 4 at the pipe entrance 21 are measured, the position and the declination of the target unit 3 can be obtained sequentially and converted into azimuth coordinates.

  Further, on the ground side, an elevating unit 30 is provided in the vicinity of the pipe inlet portion 21, and the measuring device A is lifted and lowered by the suspension wire (cable) 22 via the pulley 32. Move at a low speed near the measurement point and increase the movement speed at other locations. In addition, a data processing device (personal computer) 34 for processing data from the measuring device A and an I / F device 35 thereof are provided.

  The details are shown below.

(1-1) Calculation of target unit position from link inclination angle Inclination sensors [e.g., JA-23MA type (manufactured by Japan Aviation Electronics Corporation)] 5A, 5B (only 5B shown in FIG. 1) are provided at right angles to the link 1. The two sensitivity axes are arranged orthogonally on the inclined table 2A.

  The coordinate system in which the absolute coordinate system corresponding to the azimuth coordinate is A (XYZ), the sensitivity axes of the two inclination sensors 5A and 5B are the x and y axes, and the link longitudinal direction is the z axis is B. To do. Further, a coordinate system in which the coordinate system B is rotated around the x and y axes and the z axis coincides with the Z axis of the coordinate system A is defined as C.

The inclination of the link 1 in the x and y axis directions is φ and ψ, respectively, and the acceleration in the x and y axis directions (coordinate system B) measured by the tilt sensors 5A and 5B of the tilt table 2A are a _x and a _y and gravitational acceleration. If the direction is g,
a _x = g sin φ, a _y = g sin φ
φ = sin ⁻¹ (a _x / g), ψ = sin ⁻¹ (a _y / g)
Position of a point P in the coordinate system B is always ^B P = (0,0, l) because it is ^t, a coordinate conversion of this to the coordinate system C.

The change matrix R _y for rotation around the y axis is

同様にｘ軸回りの回転に対する変化行列Ｒ_x は

Similarly, the change matrix R _x for rotation around the x axis is

よって座標系Ｃから見た点Ｐの位置 ^CＰは

Thus the position ^C P of the point P as viewed from the coordinate system C is

よって、サンプルｉにおけるＺ軸回りの座標系Ｂの偏角をθ_i 、現在の座標系Ｃの原点を（Ｘ_i ，Ｙ_i ，Ｚ_i ）^t とおくと、絶対座標Ａで示したＰ点位置は式（４）で与えられる。

Therefore, if the deflection angle of the coordinate system B around the Z axis in the sample i is θ _i and the origin of the current coordinate system C is (X _i , Y _i , Z _i ) ^t , the point P indicated by the absolute coordinate A The position is given by equation (4).

ただし、Ｒ_z はＺ軸回りの回転変換行列で

Where R _z is the rotation transformation matrix around the Z axis.

で与えられる。よって上記式（４）は下記式（５）となる。

Given in. Therefore, the above formula (4) becomes the following formula (5).

点Ｐは次のサンプルｉ＋１でＣ座標の原点となる。また、座標系Ｃの原点初期値を（Ｘ₀ ，Ｙ₀ ，Ｚ₀ ）^t として、管入り口部２１の点の座標を与える。

The point P becomes the origin of the C coordinate in the next sample i + 1. Further, the initial value of the origin of the coordinate system C is set to (X ₀ , Y ₀ , Z ₀ ) ^t and the coordinates of the point of the pipe entrance 21 are given.

(1-2) Calculation of the rotation angle of X′-Y ′ FIG. 2 is an explanatory diagram of the calculation of the azimuth angle according to the present invention.

In sample i, the deflection angles of the magnetic markers m _Ai and m _Bi of the tube from X ′ _i measured by the target unit 3 and the measurement unit 4 are α _Ai and α _Bi . Also, let θ _{i be} the azimuth angle of the measurement unit in sample i.

Since m _Ai and m _{Bi + 1} indicate the magnetic marker of the same tube,
θ _i + α _Ai = θ _{i + 1} + α _{Bi + 1}
θ _{i + 1} = θ _i + α _Ai −α _{Bi + 1} (6)
The initial value θ ₀ of θ _i is the azimuth angle of the measuring unit 4 when the measuring device A is set (or pulled up). By substituting θ _i into the above equation (5), the coordinates of the target unit 3 can be obtained sequentially.

(1-3) Correction of the pipe tip portion Since the tip of the hole is the excavator tip position, the length from the target unit link position to the excavator tip is defined as l ₂ , and l in the above formula (5) at the end ( l + l ₂ ) and apply.

Next, the configuration of the measuring device A will be described.
(2-1) Overall Configuration FIG. 3 is a configuration diagram of the excavation tip position measurement system in the borehole depth excavation of the present invention. As shown in this figure, the measurement unit 4 includes a case 4A, a link support mechanism 4B, a tilt base 2A, a tilt sensor (X) 5A, a tilt sensor (Y) 5B, a support wheel 4C, a brake 4D, and a lock wheel (ball). 4E, a brake release solenoid 4F, a motor 4G, an encoder 4H, and a magnetic sensor [SW-271-12, HA-12 (manufactured by Makome Laboratories)] 4I. Further, the target unit 3 includes a case 3A, a link support mechanism 3B, an inclined base 2B, a support wheel 3C fixed to the case 3A, a motor 3D, an encoder 3E, a magnetic sensor 3F, and a limit switch 3G.

  This measurement system is composed of the following four parts.

[1] Measuring unit 4
The inclination angle and azimuth of the link 1 are measured. It also has a lock mechanism for determining the fixed measurement point. The ascending and descending is performed by the lifting unit 30 on the ground.

[2] Link 1
The target unit 3 and the measurement unit 4 are mechanically connected, and an inclination angle is generated between them. In order to prepare for on-site handling, it is desirable to have a telescopic mechanism or an assembly type.

[3] Target unit 3
The link 1 is connected, and the link tip 1A is held at the center of the tube at a certain distance from the measurement unit 4. Further, it has a mechanism for detecting the magnetic markers 14 and 15 arranged on the tubes 11 and 12 and detects information for calculating the azimuth angle of the entire measuring apparatus A. It is necessary to be restrained by the measurement unit 4 with respect to rotation in the link longitudinal direction. In addition, as with the measurement unit 4, the link 1 includes a mechanism in which the tilt table 2 </ b> B is freely supported with respect to rotation around the X axis and the Y axis.

[4] Lifting unit 30
An elevating unit 30 is provided in the vicinity of the pipe entrance 21, and the measuring device A is hung by a suspension wire (cable) 22 via a pulley 32 to raise and lower the entire measuring device A. Move at a low speed near the measurement point and increase the movement speed at other locations.

  Further, magnetic markers (magnets) 14 and 15 for detecting the rotation angle are provided in the vicinity of the joint portions 11A and 12A of the tubes 11 and 12.

  Further, in order to ensure the stop position, the groove 16 (see FIG. 5) is formed in the entire circumference of the joint portions 11A and 12A of the pipes 11 and 12 so that the lock wheels (balls) 4E arranged in the measurement unit 4 are engaged. Is provided.

  The measurement unit 4 is composed of the following parts.

  The measurement unit 4 is provided with two servo-type inclinometers as tilt sensors 5A and 5B on a tilt table 2A that is freely supported with respect to rotation around the X and Y axes. Further, it is assumed that the link 1 is attached to the inclined base 2A at a right angle. The inclination sensors 5A and 5B are arranged with the sensitivity axes directed toward the x axis and the y axis of the inclination table 2A, respectively.

  Thereby, the inclination with respect to the vertical axis of the link 1 can be directly measured without being influenced by the alignment between the tilt table 2A and the case 4A.

  As shown in FIG. 4, the link support mechanism 4B has a frame 4B-1 attached to the case 4A via a slide bearing 4B-2 so as to be freely rotatable about the X axis, and an inclined base 2A is provided with the slide bearing 4B-. 3 is attached to the frame 4B-1 via 3 so as to be freely rotatable about the Y axis. By adopting such a configuration, tilting can be allowed freely while restraining rotation around the longitudinal axis of the link.

  With respect to the lock wheel 4E and the brake 4D, as shown in FIG. 5, when the lock wheel 4E is fitted in the groove 16 provided on the entire circumference of the pipe joint portion 11A, the brake wheel 4E and the brake 4D are braked between the pipe inner wall 11 and the case 4A. To improve measurement accuracy by stopping at a fixed point.

  After the measurement, the brake 4D is released by the release solenoid 4F and moved upward by the index of the suspension wire (cable) 22.

  The brake 4D is released at the time of non-measurement and until it approaches the joint portion 11A of the pipe, and the clearance with the pipe inner wall is increased.

  In the magnetic sensor (proximity sensor) drive unit, as shown in FIG. 5, the rotation angle of the measuring device A is set using a magnetic marker (magnet) 14 attached to one place on the inner wall in the vicinity of the pipe joint 11 </ b> A as a mark. To detect. Specifically, after the lock wheel 4E locks the measuring device A, the motor 4G is driven to rotate the magnetic sensor (proximity sensor) 4I along the inner wall. The rotation angle is read by a rotary encoder [for example, ME-30-P (manufactured by Microtech Laboratories), MES-9 (manufactured by Harmonic Drive)] 4H, and the magnetic sensor (proximity sensor) 4I is in the ON range. The midpoint of is the magnetic marker detection angle.

  Next, the configuration of the target unit 3 is shown in FIG. The link 1 is tiltably supported by a link support mechanism 3B similar to the measurement unit 4. In order to hold the link tip at the center position of the tube, a support ring 3C is provided on the case 3A as a guide so that the link tip A comes to the center of the tube.

  Further, as described above, in order to detect the rotation of the entire measuring apparatus A, it is necessary to read the positions of the magnetic markers 14 and 15 provided on the tubes 11 and 12 at the same time. A magnetic sensor driving unit similar to that of the measurement unit 4 is provided. If the rotation direction of reading of the magnetic markers 14 and 15 is reversed every time, a curl cord or the like is considered sufficient for electrical connection with the measurement unit 4 without providing a slip ring.

  In order to measure a 40 m tube in about 5 minutes, as shown in FIG. 1, the total mass of the measuring unit 4, the link 1, the target unit 3 and the suspension wire (cable) 22 is wound up at a speed of 1 m / s or more. A hoisting machine 31 and a pulley 32 are provided. Further, since the traveling speed is lowered at the joint portion of the pipe, it has a speed control function and a measuring device 33 for measuring a rough movement distance. Furthermore, it has a tension holding mechanism for preventing the suspension wire (cable) 22 from loosening while the measuring unit 4 is applying the brake 4D.

  On the ground side, a data processing device (personal computer) 34 for processing data from the measuring device A and its I / F device 35 are provided.

  FIG. 7 is a configuration diagram of the upper end jig of the pipe of the measurement system of the present invention.

  In this figure, reference numeral 17 denotes an upper end jig of a tube, and a magnetic marker 18 indicating its reference direction is arranged.

  Next, an operation method of the measurement system of the present invention will be described.

  FIG. 8 is a diagram showing an operation flow of the measurement method of the present invention.

  (1) First, the upper end jig 17 of the pipe and the lifting unit 30 are set on the upper part of the pipe. The upper end jig 17 replaces the first pipe joint and gives an initial value of the azimuth (step S1).

  (2) Next, the link 1 is extended to a predetermined length and set in the elevating unit 30, and the brake 4D is released and lowered until the lower end of the pipe is detected. The lower end of the pipe is detected by the number of pipes set in advance in the lifting unit 30 or by a detection switch (limit switch 3G) attached to the target unit 3 (steps S2 to S3).

  (3) Next, from the lower end of the pipe, the brake 4D is set in an operating state, and the pipe 4D is raised at a low speed to the first pipe joint position (step S4).

  (4) Next, since the lock wheel 4E of the measuring unit 4 reaches the groove 16 and locks when reaching the joint portion of the pipe, the magnetic marker position of the pipe is detected and the inclination sensors 5A and 5B are read at this position. And recording (step S5).

  (5) Next, the brake 4D is released and raised to the front of the next pipe joint (steps S6 to S8).

  (6) Next, the moving speed is lowered to bring the brake 4D into an operating state and move until the lock wheel 4E is locked (steps S9 to S10).

  (7) Next, the above steps (4) to (6) are repeated until reaching the upper end jig of the pipe. Whether or not the upper end jig of the tube has been reached is determined by the amount of winding of the lifting unit 30 (step S11).

  (8) Next, when the measuring device A reaches the upper end, the measurement is stopped (step S12).

  (9) Next, it waits for a measurement data download command from the data processing device 34 (step S13), the measurement data is downloaded by the download command from the data processing device 34, and the ground side data processing device 34 calculates the position. Is performed (step S14).

  Further, the lock mechanism and the brake mechanism shown in the above embodiment may be omitted, and the measuring device may be positioned by adjusting the winding length of the hoisting machine. That is, the hoisting wire may be wound up at a constant interval by a hoisting machine, and the measurement unit may perform measurement for each point.

  The method is as follows.

(1) Set the lifting unit and the upper end jig of the pipe at the upper part of the pipe, and give the initial value of the azimuth by inserting the measuring device,
(2) Lower the measuring unit until the lower end of the pipe is detected,
(3) From the lower end of the pipe, the hoisting wire is wound up in a certain amount by a hoisting machine, and at each point, the magnetic marker position of the pipe by the magnetic sensor and the inclination angle by the inclination sensor are read and recorded at each measuring unit.
(4) The above step (3) is repeated until reaching the upper end jig of the pipe. With this configuration, the accumulated error is added to the amount of winding, so that the measurement accuracy is lower than that of the method having a lock mechanism, but the apparatus is greatly simplified and the cost can be reduced.

  In addition, this invention is not limited to the said Example, Based on the meaning of this invention, a various deformation | transformation is possible and these are not excluded from the scope of the present invention.

  The excavation tip position measurement system in the borehole depth excavation of the present invention can be used as an automatic survey system in excavation of a borehole such as soil improvement.

It is explanatory drawing of the measurement principle of the excavation tip position in the deep hole excavation of this invention. It is explanatory drawing of calculation of the azimuth which concerns on this invention. It is a block diagram of the excavation tip position measuring system in the deep hole excavation of the present invention. It is a block diagram of the link support mechanism of the measuring device which concerns on this invention. It is a block diagram of the lock wheel and magnetic sensor drive part of the measuring device which concerns on this invention. It is a block diagram of the target unit of the measuring device which concerns on this invention. It is a block diagram of the upper end jig | tool of the pipe | tube of the measuring system of this invention. It is a figure which shows the operation | movement flow of the measuring system of this invention. It is a schematic diagram of the measurement system of the excavation tip position in the conventional deep hole excavation.

Explanation of symbols

A measuring device 1 link 1A link tip 2A, 2B tilt base 3 target unit 3A, 4A case 3B, 4B link support mechanism 3C, 4C support wheel 3D, 4G motor 3E, 4H encoder 3F, 4I magnetic sensor 3G limit switch 4 measurement unit 4B-1 Frame 4B-2, 4B-3 Slide bearing 4D Brake 4E Lock wheel (ball)
4F Brake release solenoid 5A, 5B Inclination sensor (servo type inclinometer)
11-13 Pipe 11A, 12A Pipe joint 14, 15, 18 Magnetic marker 16 Groove 17 Pipe upper end jig 21 Pipe entrance 22 Hanging wire (cable)
30 Lifting unit 31 Hoisting machine 32 Pulley 33 Measuring instrument (ground side)
34 Data processing equipment (PC)
35 I / F device

Claims (5)

(A) a pipe having a plurality of pipes connected and having a magnetic marker in the vicinity of a joint portion of each pipe;
(B) a link set along the interior of the conduit and having a length approximately equal to the length of each tube;
(C) An inclination sensor disposed on an upper end of the link and disposed on an inclination table provided at a right angle to the link, and a magnetic sensor capable of circling the inner wall of the pipe at the position where the magnetic marker is disposed A measuring unit having
(D) a target unit disposed at the lower end of the link;
(E) The position of the target unit is sequentially measured based on information from an inclination sensor and a magnetic sensor mounted on the measurement unit as the suspension wire connected to the measurement unit is pulled up or down. Drilling tip position measurement system for deep hole drilling.   2. The excavation tip position measurement system in borehole depth excavation according to claim 1, wherein the inclination angle of the link with respect to the gravitational acceleration direction when the link is passed to two points of the pipe center by the inclination sensor and the magnetic sensor are adjacent to each other. An excavation tip position measurement system in borehole depth excavation, wherein the target unit position is measured based on an azimuth coordinate from a link angle obtained by measuring a declination of magnetic markers arranged on two pipes. Using the excavation tip position measurement system in the borehole depth excavation according to claim 1 or 2,
(A) setting the lifting unit and the upper end jig of the pipe on the upper part of the pipe, and giving an initial value of the azimuth by inserting a measuring device;
(B) releasing the brake and lowering the measuring unit until the lower end of the pipe is detected;
(C) From the lower end of the pipe, the brake is in an operating state, and the step of raising the joint to the position of the first pipe at a low speed;
(D) When the pipe joint is reached, the locking mechanism of the measurement unit is locked in the groove, and at this position, the magnetic marker position of the pipe by the magnetic sensor and the inclination angle by the inclination sensor are read and recorded;
(E) releasing the brake and raising to the front of the joint portion of the next pipe;
(F) lowering the moving speed to bring the brake into an operating state and moving until the wheels of the measuring unit are locked;
(G) A method for measuring a drilling tip position in a borehole depth excavation, comprising the steps of repeating the above steps (d) to (f) until reaching the upper end jig of the pipe. Using the excavation tip position measurement system in the borehole depth excavation according to claim 1 or 2,
(A) setting the lifting unit and the upper end jig of the pipe on the upper part of the pipe, and giving an initial value of the azimuth by inserting a measuring device;
(B) lowering the measurement unit until the lower end of the pipe is detected;
(C) A process of winding a suspension wire from the lower end of the pipe by a hoisting machine in increments of a certain amount, and reading and recording the magnetic marker position of the pipe by the magnetic sensor and the inclination angle by the inclination sensor at each measurement unit, and recording ,
(D) A method of measuring the position of the excavation tip in a borehole depth excavation, comprising the step of repeatedly measuring the step (c) until reaching the upper end jig of the pipe.   5. The method for measuring a drilling tip position in a borehole depth excavation according to claim 3 or 4, wherein the measurement data is obtained by a step of stopping the measurement when the measuring device reaches the upper end, and a measurement data download command from the data processing device on the ground side. An excavation tip position measuring method in borehole depth excavation, which is downloaded and the position is calculated by the data processing device.

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