JP6016010B2 - Geological and formation change detection device and detection method - Google Patents

Description

  The present invention relates to a detection device and a detection method suitable for detecting changes in geology and formation during drilling and excavation work such as quarrying and pile driving.

In civil engineering work, there is a drilling and excavation work aimed at reaching a boundary position between a specific stratum that exists deep underground. As an example, in the foundation work of a building, it is necessary to drill up to a point that reaches the support layer in order to drive the pile, but if the hole is drilled too much, the support pile cannot be stabilized. In the mining work of coal, it is necessary to pierce and blast the sandstone layer on the coal layer in order to expose the coal and excavate it. At this time, if the hole is excessively drilled, the exposure of the coal becomes unstable. Therefore, there is a need for a technique that can accurately detect the change in the formation of the excavation ground at the tip position of the excavating blade of the excavator.
As such a detection technique, as disclosed in Patent Documents 1 to 3, an acoustic sensor is attached to a drill of an excavator, and a change in geology or formation is detected in real time from a change in excavation sound acquired by the acoustic sensor. There is something.

JP-A-9-324412 JP 2001-342619 A JP 2011-38257 A

However, the conditions in the ground are extremely complex, and even in the same formation, the distribution state of moisture and the inclusion state of rocks are not necessarily uniform depending on the location or depth. In addition, when different formations are laminated, the laminated state is often greatly distorted or bent.
In this regard, the invention disclosed in Patent Document 1 observes the waveform of the excavation sound with an oscilloscope or the like, and judges changes in geology or formation by visually comparing these with the waveform and frequency data prepared in advance. . Further, the invention disclosed in Patent Document 2 creates a frequency distribution in which the amplitude of excavation sound exceeds a threshold per unit time, and collates this with the same frequency distribution data for each geology and strata prepared in advance. To determine changes in geology and strata. In the invention disclosed in Patent Document 3, the frequency spectrum of the excavation sound is acquired, and this is compared with the teacher spectrum acquired when excavating the ground equivalent to the target ground. Judgment of changes.

  Therefore, when using the techniques disclosed in Patent Documents 1 to 3, the state of the ground when these reference data prepared in advance are acquired and the state of the ground to be excavated from now on are approximate. It is a premise. However, they do not necessarily match. Therefore, in the actual site of drilling and excavation work, there has been a problem that the detection accuracy of excavation sound change is not constant.

In addition, in order to obtain a detection device corresponding to various ground conditions, it is necessary to prepare a lot of reference data before drilling and excavation work, and the user can work on reference data suitable for the target ground for excavation work. Each time you have to consider and choose. For this reason, there has been a problem that the burden of work is large and the number of work steps is large and cumbersome when viewed in terms of the entire geological / geological change detection work.
The present invention has been devised in view of the above-described problems, and the ground condition between excavation sound data acquired for detection at an excavation work site and reference data to be compared with the excavation sound data. It is an object of the present invention to provide a detection device and a detection method for a geological / geological change that can improve the nonconformity based on the difference between the two and reduce the burden of the reference data preparation work and selection work.

In order to achieve the above object, the present invention is characterized in that the geological / geological change detection method and detection apparatus according to the present invention are configured as follows.
A first aspect of a geological / geological change detection device according to the present invention is a sound collection device that acquires excavation sound of an excavator, and an acoustic analysis device that executes acoustic analysis processing based on the acquired excavation sound, The acoustic analysis device includes a sound feature amount calculating means for extracting an acoustic feature amount from the excavation sound using a function for extracting the acoustic feature amount, and an acoustic feature amount. A reference sound subspace creating means for creating a reference sound subspace to be used for acoustic analysis processing, a deviation distance calculating means for calculating a deviation distance between the acoustic feature quantity and the reference sound subspace, and a magnitude of the deviation distance A threshold setting means for setting a threshold for judging whether or not and a comparison means for judging whether or not the deviation distance exceeds the threshold, the reference sound subspace creating means is immediately after the start of excavation work by the excavator Within the first predetermined time A reference sound subspace is created from the acoustic feature amount calculated by the acoustic feature amount calculation means based on the excavation sound acquired by the sound device, and the threshold setting means is within a second predetermined time after the first predetermined time has elapsed. The threshold value is calculated from the acoustic feature amount calculated by the acoustic feature amount calculation unit based on the excavation sound acquired by the sound collector, and the comparison unit determines whether the deviation distance exceeds the threshold value after the second predetermined time has elapsed. It is characterized by executing a process for determining whether or not.

In the second aspect of the present invention, the function used by the acoustic feature quantity calculating means of the first aspect may be a higher-order local auto-correlation function. In the following description, the high-order local autocorrelation function is simply referred to as “HLAC” unless otherwise specified.
According to a third aspect of the present invention, there is provided a user interface unit that allows the user to set at least one of the first predetermined time and the second predetermined time of the first or second aspect before excavation work of the excavator. Also good.

In the fourth aspect of the present invention, the operation for controlling the operation timing of the reference sound subspace creation means, the threshold setting means, and the comparison means in accordance with the control signal supplied from the excavator of the first to third aspects. Control means may be provided.
In the fifth aspect of the present invention, the sound collecting device of the first to fourth aspects may be disposed on a drifter that moves the excavator blade of the excavator.
According to a sixth aspect of the present invention, there is provided a geological / geological change detection device according to the first to fifth aspects, and a notification device that performs a notification operation based on a determination result of a comparison unit of the geological / geological change detection device. It may be an excavator provided.

  A seventh aspect of the present invention is a geology / stratification change detection method for detecting excavation sound of an excavator and detecting a change in geology / stratum by executing acoustic analysis processing based on the acquired excavation sound. An acoustic feature quantity calculating step for extracting an acoustic feature quantity from the excavation sound using a function for extracting the acoustic feature quantity, and a reference for creating a reference sound subspace to be used for acoustic analysis processing based on the acoustic feature quantity A sound subspace creation step, a departure distance calculation step for calculating a departure distance between the acoustic feature quantity and the reference sound subspace, a threshold setting step for setting a threshold for judging the magnitude of the departure distance, and a departure distance The reference sound subspace creation step is executed within a first predetermined time immediately after the start of excavation work by the excavator, and the threshold setting step includes a comparison step for determining whether or not the threshold value exceeds the threshold value. Executed within the second predetermined time after a predetermined time, the comparison step is characterized by executing the after the second predetermined time.

  Therefore, according to the first aspect of the geological / geological change detection device to which the present invention is applied, the reference data corresponding to the geological / geological condition of the excavation target ground to be excavated is excavated along with the progress of the excavation work. Obtain promptly at the work site. And the excavation sound change at the time of excavation work is detected accurately by executing the acoustic analysis process of the excavation sound based on this reference data. Therefore, it has excellent versatility that can cope with various ground conditions.

  The second aspect of the geological / geological change detection apparatus to which the present invention is applied uses higher-order local autocorrelation as a function used by the acoustic feature quantity calculating means. Since HLAC extracts an acoustic feature quantity from a two-dimensional change pattern of an acoustic signal in a time-frequency plane, it is possible to perform feature extraction that simultaneously reflects temporal and frequency changes of the acoustic signal. In addition, the reference sound subspace is successively updated and learned by the sequential principal component analysis of HLAC. Therefore, by using this acoustic feature amount, a precise analysis reflecting the current ground condition during excavation becomes possible. Therefore, it is possible to accurately capture subtle changes in excavation sound caused by geological and strata changes.

In the third aspect of the geological / geological change detection method to which the present invention is applied, at least one of the first predetermined time and the second predetermined time can be arbitrarily set by the user. Optimal detection processing can be performed.
In the fourth aspect of the geological / geological change detection method to which the present invention is applied, the user transmits a control signal from the excavator to set the operation timing of the reference sound subspace creating means, the threshold setting means, and the comparing means. Can be controlled. Therefore, excavation work can be performed efficiently.

In the fifth aspect of the geological / geological change detection method to which the present invention is applied, the sound collecting device is disposed on the drifter that moves the excavator blade of the excavator. Regardless of the degree of progress, the sound can be collected with almost constant quality.
The sixth aspect of the geological / geological change detection method to which the present invention is applied is the notification operation based on the determination result of the geological / geological change detecting device according to the present invention and the comparing means of the geological / geological change detecting device. It is an excavator provided with a notification device for performing. Therefore, it is possible to obtain an excavator that can notify the user that the geology and the formation have changed.

1 is a block diagram of a geological / geological change detection device according to the present invention. FIG. It is a figure which shows the attachment position of a sound collector. It is a flowchart which shows the acoustic analysis process of this invention. It is a figure which shows the example of calculation of deviation distance.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(Constitution)
FIG. 1 is a block diagram of a geological / geological change detection device 10 according to the present invention.
The geological / geological change detection device 10 includes a sound collecting device 100 disposed in an excavator, an acoustic analysis device 120 that performs acoustic analysis processing based on excavation sound acquired by the sound collecting device 100, and an acoustic analysis device. The notification device 150 that notifies based on the determination result by 120, the result display device 140 that also displays the determination result by the acoustic analysis device 120, and the sound collection device 100, the notification device 150, and the acoustic analysis device 120 are interposed. A user interface 110 that performs data input / output processing, a memory for the acoustic analysis device 120, a storage device 170 that stores a binary code of a program used for the acoustic analysis processing, parameter setting values, and the like, and the parameters An operation key panel 160 is provided for changing the settings.
In the above, except for the sound collecting device 100, they are basically arranged for the user in the cabin of the excavator.

The user interface 110 includes an amplifier (not shown) that amplifies excavation sound and an AD converter that performs analog-digital conversion.
The control signal transmission device 130 from the excavator processed by the user interface 110 includes a rotation SW, an impact SW, a flushing SW, a feed forward SW, a feed backward SW, a jamming SW, a feed pressure sensor, and a manual start SW. Each signal supplied from these control signal transmission devices 130 is used for execution of learning start condition processing and end condition processing described later.

The sound collector 100 acquires excavation sound when the excavator excavates the ground. The acquired excavation sound is taken into the acoustic analyzer 120. FIG. 2 shows the mounting position of the sound collecting device in the excavator.
The acoustic analysis device 120 includes an acoustic feature quantity calculation unit 120a, a reference sound subspace creation unit 120b, a deviation distance calculation unit 120c, a threshold setting unit 120d, and a comparison unit 120e. The acoustic analysis device 120 executes acoustic analysis processing based on the excavation sound acquired by the sound collection device 100.

The acoustic feature amount calculation unit 120a extracts the acoustic feature amount from the excavation sound acquired by the sound collecting device 100 using a function for extracting the acoustic feature amount.
The reference sound subspace creation unit 120b creates a reference sound subspace used for the acoustic analysis process based on the acoustic feature amount extracted by the acoustic feature amount calculation unit 120a.
The departure distance calculation unit 120c calculates a departure distance between the acoustic feature amount extracted by the acoustic feature amount calculation unit 120a and the reference sound subspace created by the reference sound subspace creation unit 120b.

The threshold setting unit 120d sets a threshold for determining the magnitude of the departure distance calculated by the departure distance calculation unit 120c.
The comparison unit 120e determines whether or not the departure distance calculated by the departure distance calculation unit 120c exceeds the threshold set by the threshold setting unit 120d.
The notification device 150 notifies the user based on the determination result by the acoustic analysis device 120.

The result display device 140 displays the determination result by the acoustic analysis device 120 to the user.
The user interface 110 is interposed between the sound collection device 100 and the notification device 150 and the acoustic analysis device 120 and performs data input / output processing.
The memory is used for analysis processing of the acoustic analyzer 120.
The storage device 170 stores a binary code of a program used for acoustic analysis processing, parameter setting values, and the like.
The operation key panel 160 is used to change parameter settings.

(Parameter)
The parameter used for the process of this invention can be suitably changed according to excavation object ground. However, when applied to many general coal mining sites, the following definitions may be made.
Start condition continuous time S: 0 to 5 seconds Pressure value P0: 0 to 10 MPa range First predetermined time: 5 seconds Second predetermined time: 5 seconds Adjustment coefficient α: Typical value is set to 6 Is done.
End time continuous time E: 0 to 10 seconds By setting the values of the parameters in this way, in many cases, efficient acoustic analysis processing can be performed at the coal mining site. Such an embodiment of the geological / geological change detection device 10 can be made more suitable.

(Function)
FIG. 3 is a flowchart showing the acoustic analysis processing of the present invention.
First, when the user activates the excavator, the geological / geological change detection device 10 according to the present invention is activated in conjunction with the excavator. The sound collection device 100 is energized so that sound collection is possible, and the acoustic analysis device 120 prepares for initial settings and the like. The user executes a setting input operation using the operation key panel 160 as necessary.
Thereafter, acquisition of excavation sound is started by the sound collecting device 100 attached to the excavator. The user interface amplifies the acquired excavation sound with an amplifier, and further executes analog-digital conversion processing with an AD converter. Thereafter, a process of taking the digitized acoustic signal into the acoustic analyzer 120 is executed. The acoustic feature quantity is extracted from the acoustic signal thus captured by the acoustic feature quantity calculation unit 120a, and the process proceeds to step S20.
Note that the excavation sound acquisition process and the acquired excavation sound acoustic feature amount extraction process continue to be executed in parallel even when the process described later proceeds.

In step S20, whether or not to start the acoustic analysis processing in step S30 and later is controlled by one of the following control signals 130 of (1) and (2).
(1) An input signal in which all three SWs of rotation SW, impact SW and flushing SW are ON, and an input signal transmitted when the feed pressure continuously exceeds P0 [MPa] for S [seconds] ( 2) Input signal when manual start SW is ON Note that the feed pressure signal is amplified by an amplifier, further subjected to analog-digital conversion processing by an AD converter, and then used for processing by the acoustic analyzer 120.

When the input signal of any one of (1) and (2) is received, the acoustic analysis process proceeds to step S30, and in this step S30, the reference sound subspace creating unit 120b is executed in parallel. A reference sound learning process is executed from the acoustic feature quantity extracted through the excavation sound acquisition process and the acoustic feature quantity process. In this way, a reference sound subspace is created as reference data for the ground currently being excavated.
This reference sound subspace creation process (step S30) is executed for a first predetermined time which is one of the parameters. When the first predetermined time is finished and the learning of the reference sound is finished, the parameters of the reference sound subspace learned in step S30 are stored in the storage device 170 and transferred to the processing in the next step S40.

In step S40, the deviation distance calculation unit 120c calculates the deviation distance from the reference sound subspace of the acoustic feature amount extracted through the excavation sound acquisition process and the acoustic feature quantity extraction process.
This deviation distance calculation process (step S40) is executed for a second predetermined time which is one of the parameters. During this second predetermined time, the calculated deviation distance is sequentially transferred to the next threshold value setting process (step S50) and used for threshold value generation in step S50. When the second predetermined time ends and this process ends, the acoustic analysis process proceeds to step S60. The deviation distance and threshold parameters calculated in steps S40 and S50 are stored in the storage device 170.
In step S60, a threshold for the deviation distance is set according to the following procedure. Find the average μ and standard deviation σ of the deviation distance (120d (n), n = 1, ..., N) calculated during the second predetermined time,

調整係数αを用いて閾値θを次式により算出する。

The threshold value θ is calculated by the following equation using the adjustment coefficient α.

In step S60, the comparison unit 120e performs an acoustic change detection process. The deviation distance is calculated through the deviation distance calculation process (step S40) from the acoustic feature quantity extracted through the excavation sound acquisition process and the acoustic feature quantity extraction process. The calculated deviation distance is compared with the set threshold value.
If the calculated deviation distance is smaller than the threshold, the process proceeds to step S70. This calculates the deviation distance by executing the same process as in step S60. Then, the process proceeds to step S80, and the comparison unit 120e compares the magnitude with the threshold value.
Here, if the calculated deviation distance is smaller than the threshold value, the process returns to step S70 again, and the processes of step S70 and step S80 are repeated unless the interruption process is executed.

  On the other hand, when the calculated deviation distance is equal to or greater than the threshold, the process proceeds to step S90. In step S <b> 90, the acoustic analysis device 120 determines that a change in geology / stratum has occurred at the site where the drill bit is currently excavated, and transmits a signal to the notification device 150 via the user interface 110. Thereby, the notification device 150 sounds a warning buzzer to notify the user. The acoustic analysis device 120 transmits a signal to the result display device 140 via the user interface 110. As a result, the result display device 140 visually displays the result for the user.

The acoustic analysis device 120 is controlled by the control signal 130 of any of the following (4) to (6), whether or not to terminate the acoustic analysis processing. In particular,
(4) Input signal when jamming SW is turned ON (5) Input signal when feed reverse SW is turned ON (6) When feed forward SW is OFF for more than 120E [sec] Input signal When any one of the above (4) to (6) is received, the acoustic analysis process is terminated, and a transition is made to a standby state.
The above is the basic flow of the acoustic analysis processing according to the present invention.

(effect)
The geological / geological change detection device 10 according to the present invention accurately detects a change in excavation sound during excavation work by executing the acoustic analysis process described above. Therefore, there is an advantageous effect that even if the ground to be excavated is in various geological and geological conditions, even if the environmental conditions differ from work to work.

FIG. 4 shows an example of the processing described in steps S30 to S60. In FIG. 4, the horizontal axis represents time and the vertical axis represents the deviation distance.
In the acoustic analysis processing shown in FIG. 4, the threshold for the deviation distance for determining that the geology / stratum has changed is obtained from the expected value and the standard deviation of the deviation distance calculated in 5 seconds immediately after the reference sound learning. ing. Drilling started at around 00: 01.9, and the reference sound was learned for 5 seconds immediately after that. Then, the threshold value for detecting the acoustic change is obtained from the expected value of the deviation distance calculated in the next 5 seconds and the standard deviation, and the deviation distance and the threshold value are compared in the subsequent sections. Then, it is determined that the geology and strata started to change from 00: 25.7 when the departure distance exceeded the threshold.

DESCRIPTION OF SYMBOLS 10 Geological / geological change detection apparatus 100 Sound collecting apparatus 110 User interface 120 Acoustic analysis apparatus 120a Acoustic feature amount calculation part 120b Reference sound subspace creation part 120c Deviation distance calculation part 120d Threshold setting part 120e Comparison part 130 Control signal 140 Result display apparatus 150 Notification Device 160 Operation Key Panel 170 Storage Device

Claims (7)

A geological / geological change detection device comprising: a sound collection device that acquires excavation sound of an excavator; and an acoustic analysis device that executes acoustic analysis processing based on the acquired excavation sound,
The acoustic analyzer is
An acoustic feature quantity calculating means for extracting an acoustic feature quantity from the excavation sound using a function for extracting an acoustic feature quantity;
A reference sound subspace creating means for creating a reference sound subspace to be used for the acoustic analysis processing based on the acoustic feature amount;
A deviation distance calculating means for calculating a deviation distance between the acoustic feature quantity and the reference sound subspace;
Threshold setting means for setting a threshold for determining the magnitude of the deviation distance;
Comparing means for determining whether the deviation distance exceeds the threshold;
With
The reference sound subspace creating means calculates the acoustic feature calculated by the acoustic feature amount calculation means based on excavation sound acquired by the sound collector within a first predetermined time immediately after the start of excavation work by the excavator. From the quantity, create the reference sound subspace,
The threshold setting unit is configured to calculate the acoustic feature amount calculated by the acoustic feature amount calculation unit based on the excavation sound acquired by the sound collector within a second predetermined time after the first predetermined time has elapsed. Calculate the threshold,
The comparison means is configured to execute a process of determining whether or not a deviation distance exceeds the threshold value after the second predetermined time has elapsed.   The geological / geological change detection device according to claim 1, wherein the function used by the acoustic feature quantity calculating unit is a high-order local autocorrelation function.   The geology / stratum according to claim 1 or 2, further comprising a user interface unit that allows a user to set at least one of the first predetermined time and the second predetermined time before excavation work of the excavator. Change detection device.   4. An operation control unit that controls operation timings of the reference sound subspace creation unit, the threshold setting unit, and the comparison unit in accordance with a control signal supplied from the excavator. The geological / geological change detection device according to any one of the above. 5. The geological / geological change detection device according to claim 1, wherein the sound collecting device is disposed on a drifter that moves a drilling blade of the excavator.   The geological / geological change detection device according to any one of claims 1 to 5, and a notification device that performs a notification operation based on a determination result of the comparison unit of the geological / geological change detection device. Excavator characterized by. A geological / geological change detection method for detecting a geological / geological change by acquiring excavation sound of an excavator and executing acoustic analysis processing based on the acquired excavated sound,
An acoustic feature quantity calculating step for extracting an acoustic feature quantity from the excavation sound using a function for extracting the acoustic feature quantity;
A reference sound subspace creating step for creating a reference sound subspace used for the acoustic analysis processing based on the acoustic feature amount;
A deviation distance calculating step of calculating a deviation distance between the acoustic feature quantity and the reference sound subspace;
A threshold setting step for setting a threshold for determining the magnitude of the deviation distance;
A comparing step of determining whether the deviation distance exceeds the threshold;
With
The reference sound subspace creation step is executed within a first predetermined time immediately after the start of excavation work by the excavator,
The threshold setting step is executed within a second predetermined time after the first predetermined time has elapsed,
The comparison step is executed after elapse of the second predetermined time.

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