JP2017223000A - Device, method, and program for determining arrival to support layer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide highly reliable device, method, and program for determining arrival to support layer.SOLUTION: Device 1 for determining arrival to a support layer is a determination device of arrival to a support layer, and includes an A/D converter 20 that converts an analogue current value iof an electric motor that rotates and drives an excavator for excavating a ground and outputs a digital current value, and a controller 4 having low-pass filter means for removing a noise from the digital current value and outputting a corrected current value. The device for determining arrival to support layer outputs a signal indicating arrival to the support layer, based on a time width when the corrected current value reaches or exceeds a preset current threshold value.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a support layer arrival determination device, a support layer arrival determination method, and a support layer arrival determination program.

As a method of pile driving work, there is a method in which a pile or the like reaches a support layer by excavating the ground by rotating the pile itself or an auger drill (hereinafter referred to as “excavator”) with an electric motor.
Here, conventionally, whether or not the excavator has reached the support layer is determined by the person in charge at the site visually observing the chart paper on which the waveform of the motor current value loaded on the electric motor is printed. This is done depending on whether the value has increased.
This utilizes the fact that when the excavator reaches the support layer, the electric motor is overloaded and the motor current value increases.
However, since the printed motor current value waveform includes various noises such as single noise (high amplitude appearing in a relatively short time) and high frequency noise due to the environment of the construction site, for example, It may be determined that the support layer has been reached with the discovery of a single noise.
Therefore, the judgment method based on visual observation as described above is subjective by the on-site manager, and has a problem that the objectivity is poor and the reliability is low.
Moreover, although patent document 1 is a method of determining a base-surface position based on the load current value and suspension load of the electric motor of an excavator, it does not mention the noise problem and its solution means.

JP 2012-149463 A

  Then, this invention is made | formed in view of the said problem, Comprising: It aims at providing the support layer arrival determination apparatus, support layer arrival determination method, and support layer arrival determination program with high reliability.

In order to achieve the above object, the following configuration is used.
(1) The support layer arrival judging device of the present invention is
A determination device for determining the arrival of a support layer, an A / D converter that converts an analog current value of an electric motor that rotationally drives an excavator that excavates the ground, and outputs a digital current value; and from the digital current value A low-pass filter means for removing noise and outputting a corrected current value, and having reached the support layer based on a time width in which the corrected current value is equal to or greater than a preset current threshold value. Output a signal that represents
(2) In the configuration of (1) above,
When the time width is equal to or greater than a preset time width threshold, a signal indicating that the support layer has been reached is output.
(3) In the configuration of (1) or (2) above,
For each time width in which the correction current value is equal to or greater than a preset current threshold value, the correction current value is integrated over time to obtain a current integral value, and the current integral value is equal to or greater than a preset integration threshold value. In this case, a signal indicating that the support layer has been reached is output.
(4) The support layer arrival determination method of the present invention includes:
A determination method for determining arrival of a support layer, a conversion step of converting an analog current value of an electric motor that rotationally drives an excavator for excavating the ground and outputting a digital current value, and removing noise from the digital current value A noise removal step for outputting a corrected current value and a determination output step for outputting a signal indicating that the correction current value has reached the support layer based on a time width in which the corrected current value is equal to or greater than a preset current threshold value. .
(5) The support layer arrival determination program of the present invention includes:
A determination program for causing a computer to determine the arrival of a support layer, wherein the computer digitally converts a motor current value of an electric motor that rotationally drives an excavator for excavating the ground and outputs a digital current value; The low-pass filter means for removing the noise from the digital current value and outputting the corrected current value and the time width when the corrected current value is equal to or greater than a preset current threshold value represents that the support layer has been reached. It functions as a means for outputting a signal.

  According to the present invention, it is possible to provide a support layer arrival determination device, a support layer arrival determination method, and a support layer arrival determination program with high reliability.

It is a block diagram of a support layer arrival determination apparatus. It is a block diagram of a support layer arrival judging program concerning a 1st embodiment. It is a block diagram of a support layer arrival judging program concerning a 2nd embodiment. It is a graph showing the relationship between a digital electric current value and time. (A) is a graph showing the relationship between the correction current value after passing through the low-pass filter and time, and (b) is a graph showing the relationship between time width and time exceeding the current threshold.

  Hereinafter, a first mode for carrying out the present invention (hereinafter referred to as a first embodiment) will be described in detail with reference to the drawings.

(First embodiment)
(Support layer arrival judgment device)
As shown in FIG. 1, the support layer arrival determination device 1 includes a CPU 10, an A / D conversion device 20, an I / O device 30, a main memory 40, an image memory 50, and a communication device 60. The control device 4 is configured with the image memory 50, and each device is hardware connected to each other by wiring.
Further, the support layer arrival determination device 1 is connected to the current detection unit of the external electric motor and is connected to the external management computer 2.
Hereinafter, each device will be described individually.

  The CPU 10 reads the support layer arrival determination program 100, which is software, from the main memory 40 and sequentially executes it, for example, generates a system clock with a period of 1 ms, and operates each component for each period in synchronization with the system clock. The support layer arrival determination program 100 will be described in detail separately. Hereinafter, unless otherwise specified, the time width is used in the same meaning as the number of system clocks.

A / D converter 20, an analog current value i _a of the electric motor for rotating the excavator for excavating the ground is input, converts the analog value into a digital value and outputs the digital current value i _d.

  The I / O device 30 includes an input device 31 that inputs an external start signal and a set value, a display device 32 that displays a current waveform, a support layer arrival determination result, and the like, and a notification device 33 that outputs a notification signal. Although the I / O device 30 may include a printing device (not shown) that prints the current waveform, the support layer arrival determination result, and the like, the printing device is an external module different from the support layer arrival determination device 1, and the I / O device 30 The O device 30 may be connected. The I / O device 30 may be an external module different from the support layer arrival determination device 1.

  In the main memory 40, a support layer arrival determination program 100, which will be described later, is developed.

The image memory 50 stores data to be displayed on the display device 32.
The communication device 60 transmits and receives data to and from the external management computer 2 through a network such as wireless communication, wired communication, and a public line. The management computer 2 is appropriately provided with a monitor 3.

The control device 4 includes a CPU 10, a main memory 40, and an image memory 50. The main memory 40 includes a low-pass filter means 120 that removes high-frequency noise from a digital current value and outputs a corrected current value, which will be described later. The layer arrival determination program 100 is developed.
Then, as shown in FIG. 2, the support layer arrival determination device 1, a signal indicating that on the basis of the duration tB the correction current i _r becomes current threshold i _th or more set in advance, and reaches the support layer Is output to the display device 32 and the notification device 33.

(Support layer arrival determination method and support layer arrival determination program)
Next, the support layer arrival determination program 100 will be described, which also serves as an explanation of a support layer arrival determination method that is a determination method for determining support layer arrival.
FIG. 2 shows a block diagram of the support layer arrival determination program 100.
As shown in FIG. 1, the support layer arrival determination program 100 is software developed in the main memory 40. Specifically, as shown in FIG. 2, the support layer arrival determination program 100 is a determination program for causing a computer to determine the support layer arrival. A / D conversion means 110 for digitally converting a motor current value of an electric motor for rotationally driving an excavator for excavating the ground to output a digital current value, and correcting current by removing noise from the digital current value Low-pass filter means 120 for outputting a value, image memory means 130, first comparison means 140, current register 150, counter means 160, second comparison means 170, and time width register 180 function as a correction current. Based on the time width in which the value is equal to or greater than the preset current threshold, a signal indicating that the support layer has been reached is output. To function as a means.
Then, the analog current value i _a of the electric motor for rotating the excavator for excavating the ground and digital conversion and outputs a digital current value i _d, to remove high frequency noise such as white noise from the digital current value i _d and outputs a correction current i _r, the correction current i _r is based on the duration tB as a preset current threshold i _th above, the display a signal indicating that it has reached the supporting layer 32 and the notification device 33 Output to.

Hereinafter, the support layer arrival determination program 100 will be described along the signal flow with the analog current value ia as _a base point.
As shown in FIG. 2, first, an analog current value i _a of the electric motor for rotating the excavator for excavating the ground is input to the A / D converter 110.
Analog current value _{i a} is inputted the A / D converter 110 converts the analog current value _{i a} the digital current value _{i d} (conversion step), the resulting digital current value _{i d,} the low-pass filter means 120 And output to the image memory means 130.
Image memory means 130 digital current value i _d, which is input to is output further to a display device 32, the screen of the display device 32, for example, is displayed graph as shown in FIG.
The graph shown in FIG. 4 is a waveform when the vertical axis represents the digital current value _id and the horizontal axis represents time t. The waveform includes single noise and various noises caused by the environment of the construction site. It remains.

Returning to FIG. 2, the low-pass filter unit 120 passes the low-pass filter in which a predetermined cutoff frequency is set with respect to the input digital current value _id , and the corrected current value i _r from which the high-frequency noise is removed. Is output to the first comparison means 140 (noise removal step). The cut-off frequency may be set in advance based on field surveys and experiences, and may be changed by input from the input device 31.
Further, the low-pass filter unit 120 outputs the correction current value _ir to the image memory unit 130.
The correction is inputted to the image memory unit 130 the current value i _r is output further to a display device 32, the screen of the display device 32, for example, is displayed graph as shown in FIG. 5 (a) .
The graph shown in FIG. 5 (a), the vertical axis is the corrected current value i _r, a waveform when the horizontal axis represents time t, is through the digital current value i _d of FIG. 4 to the low-pass filter Therefore, the high frequency noise is removed.

Returning to FIG. 2, the first comparison unit 140 compares the input correction current value _ir with a preset current threshold value i _th .
The current threshold i _th is set in advance based on field surveys and experiences, and is stored in the current register 150. Note that the current threshold value i _th may be changed by an input from the input device 31.
Then, the first comparison unit 140 performs the above comparison for each cycle of the system clock, and outputs, for example, “1” which is an ON signal when the correction current value _ir becomes equal to or greater than the current threshold value i _th. when the correction current i _r becomes less than the current threshold value i _th, and outputs, for example an oFF signal "0" each time the comparison, outputs an oN signal or oFF signal to the counter means 160.

The counter means 160 receives the on signal or the off signal from the first comparison means 140 and the CPU 10 receives the system clock signal corresponding to the time t.
Counter means 160, from the time t _n the ON signal is input, then measures the time width tB _n of between time t _'n the OFF signal is input, the time width tB _n second comparing means In addition to outputting to 170, the time width is reset to prepare for the next measurement. Incidentally, the measurement of the duration tB _n, 'well with the system clock number counted until _n, the time t' from the time point t _n time t may be obtained by subtracting the time at t _n from the time of _n.

The second comparison means 170 receives the time width tB _n from the counter means 160 and the time width threshold tB _th from the time width register 180. The time width threshold value tB _th is set in advance based on field surveys and experiences and is stored in the time width register 180. A time width threshold value tB _th larger than the assumed single noise time width is adopted. As a result, it is possible to suppress erroneous determination of single noise as reaching the support layer. The time width threshold tB _th may be changed by an input from the input device 31.
The second comparing means 170 compares the input time width tB _n with a preset time width threshold tB _th .
The second comparison unit 170 performs the above comparison every time the time width tB _n is input from the counter unit 160. When the time width tB _n becomes _equal to or larger than the time width threshold value tB _th , for example, an ON signal is used. A certain “1” is output to the display device 32 and the notification device 33 (determination output step).

  The display device 32 to which the ON signal is input from the second comparison unit 170 displays that the support layer has been reached, or emits a sound or light indicating that the notification device 33 has reached the support layer. 32 and the person around the notification device 33 can recognize that the excavator has reached the support layer.

Next, the above-described processing contents from the first comparison unit 140 to the second comparison unit 170 will be schematically described with reference to FIGS. 5 (a) and 5 (b).
As shown in FIG. 5A, in the graph, the current threshold value i _th is represented by a broken line parallel to the time axis.
From the time _{t 1 at} which the correction current _{i r} becomes current threshold _{i th} or more, then the correction current _{i r} measures the time width tB ₁ of between time t _'1 be less than the current threshold value _{i th.}
Then, comparing the time width tB ₁ with the preset time width threshold value tB _th , as shown in FIG. 5B, the time width tB ₁ is smaller, so the time width tB ₁ is equal to the time width threshold value tB. less than _th, in this case, at time t _'1, no determination has reached the support layer.

Subsequently, when the time has reached the time t ₂ and passed again corrected current value i _r becomes current threshold i _th or more, from the time t _2, time t the correction current i _r becomes less than the current threshold value i _th ' measuring the duration tB ₂ between up to _2.
Next, comparing the time width tB ₂ with a preset time width threshold value tB _th , as shown in FIG. 5B, the time width tB ₂ is smaller, so the time width tB ₂ is equal to the time width threshold value. less than tB _th, also in this case, at time t _'2, does not determine the reached the supporting layer.

Upon reaching the time point _{t 3} with the passage of further time, again corrected current value _{i r} becomes current threshold _{i th} or more, from the point _{t 3,} time t _'3 in which the correction current _{i r} becomes less than the current threshold value _{i th} the duration tB ₃ of until the measurement.
Then, comparing the time width tB ₃ with the preset time width threshold value tB _th , as shown in FIG. 5B, the time width tB ₃ is larger, so the time width tB ₃ is equal to the time width threshold value tB. _In this case, it is determined that the support layer has been reached at time t ′ ₃ .

Note that further time reaches time _{t 4, t 5, t 6} has elapsed, the correction current _{i r} becomes current threshold _{i th} above again, prior to these time point, that is t _'3 of Since it has already been determined that the support layer has been reached, it may not be determined again. That is, when it is determined that the support layer has been reached at time t ′ ₃ , the support layer arrival determination program may be terminated.
In this way, the support layer arrival determination program 100 can automatically determine that the support layer has been reached.

The image memory unit 130, a digital current value i _d and the correction current i _r is input, for example, the correction current i as shown in the waveform and FIG digital current value i _d, as shown in FIG. 4 5 (a) Data for displaying the waveform of _r is output to the display device 32.
By doing so, it is possible to determine whether or not the support layer has been reached based on the overload time width of the electric motor without erroneously determining single noise.

(Second Embodiment)
Next, the second embodiment will be described in detail.
The second embodiment and the first embodiment, unlike the processing of a signal of the correction current value i _r has passed through the low-pass filter, since the other parts are common, in the following description, the correction current value in the second embodiment signal processing i _r focuses on, it might be omitted in the common parts.

As shown in FIG. 3, the low-pass filter unit 220 outputs the correction current value _ir to the third comparison unit 240 and the image memory unit 230, and also outputs to the integration unit 260 described later.

The third comparison unit 240 performs comparison for each cycle of the system clock, and when the correction current value _ir becomes equal to or greater than the current threshold value i _th , for example, outputs “1” that is an ON signal, and the correction current value When i _r becomes less than the current threshold i _th , for example, “0”, which is an off signal, is output, and an on signal or an off signal is output to the integrating means 260 every time comparison is performed.
The current threshold i _th is set in advance based on field surveys and experiences and stored in the current register 250.

The integration means 260 stores the correction current value i _rn at the time point t _n when the ON signal is input, and if the signal input at the time point t _{n + 1} one cycle later is the ON signal, It performs arithmetic processing for obtaining the current integral ii _n a correction current value _{i rn + 1} at time _{t n + 1} in addition to the previous correction current _{i rn,} and outputs the current integral ii _n to the fourth comparison means 270, and later, This process is repeated each time an ON signal is input.
Then, the integrating means 260, when the off signal is input, resets the stored current integral ii _n, to prepare for the next processing.

The fourth comparison means 270 receives the current integration value ii _n from the integration means 260 and the integration threshold value ii _th from the integration register 280. The integration threshold ii _th is set in advance based on field surveys and experiences and stored in the integration register 280. The integration threshold ii _th may be changed by an input from the input device 31.

The fourth comparison means 270 compares the input current integration value ii _n with a preset integration threshold value ii _th .
The fourth comparison unit 270 performs the above comparison every time the current integration value ii _n is input from the integration unit 260. When the current integration value ii _n is _equal to or greater than the integration threshold value ii _th , for example, an on signal '1' is output to the display device 32 and the notification device 33. The current integral value ii _n are corresponding to the integral is not limited to what is computed as described above, the corrected current value i _r at time width correction current i _r becomes current threshold i _th or more times Any value is acceptable.

  By setting it as the above structure, it can be determined based on the magnitude | size of the overload of an electric motor whether it reached | attained the support layer, without erroneously determining single noise.

  The preferred embodiment of the present invention has been described in detail above, but the support layer arrival determination device, the support layer arrival determination method, and the support layer arrival determination program according to the present invention are not limited to the above-described embodiments, and are claimed. Various modifications and changes are possible within the scope of the gist of the present invention described in the above.

For example, the digital current value i _d, in addition to applying a low pass filter, if necessary, further after applying a bandpass filter or a notch filter for removing commercial frequency noise 50Hz or 60 Hz, the first You may input into the comparison means 140 or the 3rd comparison means 240. FIG.
Thereby, since the support layer arrival determination can be performed based on the waveform from which the commercial frequency noise is removed, the determination accuracy is improved.

Further, the analog current value i _a, placed in the buffer of the high input impedance, a high-frequency noise from the outside after removing an analog filter, may be converted into digital current value i _d.

Further, in order to remove the noise of the digital current value i _d, it performs a spectrum analysis of the digital current value i _d by Fourier transform, after removing the predetermined frequency or more frequency components may be the inverse Fourier transform.

  In addition, since the signal analysis of the electric motor current value is not indispensable for the time from the start of pile driving to the arrival of the support layer, the window function for the time axis is applied in the expected support layer arrival time zone, and the window function The signal analysis may be performed only within. Thereby, the memory capacity of the computer can be saved.

In addition, although 1st Embodiment and 2nd Embodiment were demonstrated separately above, you may combine these.
In other words, the support layer arrival determination device is a determination device for determining support layer arrival, and converts an analog current value of an electric motor that rotationally drives an excavator that excavates the ground to output a digital current value. A conversion device and a control device having low-pass filter means for outputting a corrected current value by removing noise from the digital current value, and a time width in which the corrected current value is equal to or greater than a preset current threshold is preset. In the case where the time width is equal to or greater than the threshold value (first embodiment) and the current integral value is equal to or greater than the preset integral threshold value (second embodiment), it indicates that the support layer has been reached. A signal may be output.
The support layer arrival determination device is a determination device that determines support layer arrival, and converts an analog current value of an electric motor that rotationally drives an excavator that excavates the ground to output a digital current value. A conversion device and a control device having low-pass filter means for outputting a corrected current value by removing noise from the digital current value, and a time width in which the corrected current value is equal to or greater than a preset current threshold is preset. When the time width is equal to or greater than the threshold value (first embodiment), the first signal indicating that the support layer has been reached is output, and in parallel, the current integral value is equal to or greater than the preset integral threshold value. In the second embodiment, when the second signal representing the arrival at the support layer is output and only one of the first signal and the second signal is output, the first signal is prioritized. Represents reaching May output items, may continue measurement ignores the first signal and the second signal.
Thus, since the arrival of the support layer is determined by different determination criteria, the reliability of the determination of arrival of the support layer is further improved.

  According to the present invention, since the analog current value of the electric motor is converted and the digital current value is output, the arrival of the support layer can be automatically determined by the computer based on the corrected current value from which noise has been removed, so that the reliability is high. A support layer arrival determination device, a support layer arrival determination method, and a support layer arrival determination program can be provided.

  According to the present invention, the arrival of the support layer is determined based on the corrected current value obtained by removing the high frequency noise from the digital current value. Therefore, the arrival of the support layer can be automatically determined without erroneous determination due to the influence of the high frequency noise.

  According to the present invention, when the time width is equal to or greater than a predetermined time width threshold, a signal indicating that the support layer has been reached is output, so that it is supported without erroneously determining single noise as reaching the support layer. Automatic determination of layer arrival.

  According to the present invention, since the correction current value is determined based on a time width that is equal to or greater than a preset current threshold value, noise removal can be calculated without going through a Fourier transform or spectrum analysis with a large calculation load, and in real time. It can be determined that the support layer has been reached.

  According to the present invention, since the determination is made based on the current integration value in the time width in which the correction current value is equal to or greater than a preset current threshold, single noise can be more accurately removed.

DESCRIPTION OF SYMBOLS 1 Support layer arrival determination apparatus 2 Management computer 3 Monitor 4 Control apparatus 10 CPU
20 A / D conversion device 30 I / O device 31 Input device 32 Display device 33 Notification device 40 Main memory 50 Image memory 60 Communication device 100 Support layer arrival determination program 110 A / D conversion means 120 Low-pass filter means 130 Image memory means 140 First comparison means 150 Current register 160 Counter means 170 Second comparison means 180 Time width register 210 A / D conversion means 220 Low-pass filter means 230 Image memory means 240 Third comparison means 250 Current register 260 Integration means 270 Fourth comparison means 280 integration register ia analog current value id digital current value ii _n current integral _{ii th} integral threshold _{i r} corrected current value _{i rn} corrected current value _{i th} current threshold t time tB _n duration _{tB th} time width threshold

Claims (5)

A determination device for determining support layer arrival,
An A / D converter that converts an analog current value of an electric motor that rotationally drives an excavator that excavates the ground and outputs a digital current value;
A control device having low-pass filter means for removing noise from the digital current value and outputting a corrected current value,
A support layer arrival determination device characterized in that a signal indicating that the correction layer has reached the support layer is output based on a time width in which the correction current value is equal to or greater than a preset current threshold value.   The support layer arrival determination device according to claim 1, wherein when the time width is equal to or greater than a predetermined time width threshold, a signal indicating that the support layer has been reached is output. For each time width in which the correction current value is equal to or greater than a preset current threshold, the correction current value is integrated over time to obtain a current integral value,
3. The support layer arrival determination device according to claim 1, wherein when the current integration value is equal to or greater than a preset integration threshold value, a signal indicating that the current has reached the support layer is output. A determination method for determining the arrival of a support layer,
A conversion step of converting an analog current value of an electric motor that rotationally drives an excavator that excavates the ground and outputting a digital current value;
A noise removing step of removing noise from the digital current value and outputting a corrected current value;
A support layer arrival determination method, comprising: a determination output step of outputting a signal indicating that the correction current value has reached a support layer based on a time width that is equal to or greater than a preset current threshold value. A determination program for causing a computer to determine the arrival of a support layer,
A / D conversion means for digitally converting a motor current value of an electric motor that rotationally drives an excavator for excavating the ground and outputting a digital current value;
Low-pass filter means for removing noise from the digital current value and outputting a corrected current value;
A support layer arrival determination program that functions as means for outputting a signal indicating that the correction current value has reached a support layer based on a time width that is equal to or greater than a preset current threshold value.

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