CN110468890A - A kind of ultrasonic drilled-hole inspecting method based on FPGA - Google Patents
A kind of ultrasonic drilled-hole inspecting method based on FPGA Download PDFInfo
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- CN110468890A CN110468890A CN201910773492.0A CN201910773492A CN110468890A CN 110468890 A CN110468890 A CN 110468890A CN 201910773492 A CN201910773492 A CN 201910773492A CN 110468890 A CN110468890 A CN 110468890A
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- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D33/00—Testing foundations or foundation structures
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Abstract
The ultrasonic drilled-hole inspecting method based on FPGA that the present invention relates to a kind of, by installing single chip control module and FPGA signal processing module in winch mechanism, control winch transfers ultrasonic probe along mud-filled drill center with given pace, in probe decentralization process, when measuring point sound of one group of (four) the sound duration of certain depth distance measurement as the depth.In this way, can calculate the aperture value to drill at different depth by record ultrasonic reflections time and reflected intensity from aperture to bottom hole and can reflect hole wall situation, host computer records the measuring point sound duration of different depth and calculates the depth aperture.When measuring probe completes primary decline process, host computer can draw the hole wall sectional view of measured hole.When holding suspension centre is constant during promoting probe and wirerope is vertical for winch mechanism, then the verticality parameter of the available pore-forming of hole wall sectional view by institute's gaging hole.
Description
Technical field
The present invention relates to a kind of ultrasonic drilled-hole inspecting method and system, especially a kind of ultrasonic drilled-hole inspectings based on FPGA
Method belongs to engineering Inspection Technique field.
Background technique
Heavy construction, bridge, subway and marine engineering generally use the deep foundations form such as various bored concrete piles.Traditional pore-forming
Quality testing uses lining rope to measure hole depth, and reinforcing bar visits cage and measures aperture, and verticality is using inspection wirerope verticality and hangs tight stake
The variation measurement of wirerope after hammer oscilaltion, method is more coarse, and precision is relatively low, has been unable to satisfy large-diameter long pile
Hole quality inspection specifications requirement.
Ultrasonic wave refers to that frequency is higher than the mechanical wave of 20000Hz.Ultrasonic wave has the characteristic that frequency is high, wavelength is short, simultaneously
With good directionality, ultrasonic wave penetration power is strong, and can be the advantages of generating ultrasonic wave total reflection on interface.Supersonic reflection method
It is presently the most one of advanced hole quality detection method, can disposably be obtained including aperture, hole depth, hole perpendicularity and hole
Wall-like condition etc. influences nearly all parameter of hole quality, and detection efficiency is fast, precision is high.The subterranean railway in current some cities or
Supersonic inspection of bored hole instrument, while 981 deep water semi-submersible drilling platform of offshore oil, boat are largely used in person's urban rail transit construction
It is also all being used in the large-scale key project of a batch such as the island Shan Lian engineering, Taizhou Yangtze Bridge country.
Mainly had using the company of ultrasonic reflection method drilled-hole inspecting technology both at home and abroad at present: Japanese KODEN company, Wuhan Tian
Great mansion company, Shanghai East Sea station, upper marial rocks connection company etc..The drilled-hole inspecting equipment of domestic-developed is mainly based upon high-performance monolithic
Machine, and external DM604 type product distinguishes hole wall echo and noise, oscillation-damped using unique DSP signal processing technology
Echo is better than home products in terms of detection effect.
Since dsp processor does not get rid of traditional CPU (Central Processing Unit, central processing unit) sequence
The mode of work, especially dsp processor using software instruction sequence execution by the way of, single DSP digital signal processor
Data processing rate is extremely difficult to the demand of high-performance high speed real-time system.Therefore use new electronic device with meet it is ultrasonic at
It is imperative that the high-speed data processing speed of hole detection system requires.
FPGA (Field Programmable Gate Array, field programmable gate array) device uses devices at full hardware simultaneously
The structure that row executes, the data processing speed advantage that can not be matched in excellence or beauty with DSP general processor.Ultrasonic pore-forming is developed using FPGA
The hardware components of detection system, parallel processing (including emit and receive) ultrasonic signal, use IP kernel built in FPGA
(Intellectual Property core, IP core) carries out Digital Signal Processing, it is possible to reduce the peripheral hardware of system, tool
There are the low-power consumption of realization system, the possibility of miniaturization.
Summary of the invention
Technical problems to be solved
In order to avoid the shortcomings of the prior art, the present invention proposes a kind of ultrasonic drilled-hole inspecting method based on FPGA.
Technical solution
A kind of ultrasonic drilled-hole inspecting method based on FPGA, it is characterised in that steps are as follows:
Step 1: single chip control module and FPGA signal processing module, single chip control module are installed in winch mechanism
It is connect with host computer, winch mechanism, FPGA signal processing module is connect with host computer, ultrasonic probe；
Step 2: host computer sends control winch mechanism signal to single chip control module, sends out to FPGA signal processing module
Acquisition signal is sent, FPGA signal processing module sends ultrasonic signal to ultrasonic probe；
Step 3: winch mechanism transfers ultrasonic probe along drill center with given pace, lets off under ultrasonic probe
Cheng Zhong, every one group of 4 ultrasound echo signal of certain depth distance measurement；
Step 4: ultrasound echo signal sends host computer to after being filtered by FPGA signal processing module；
Step 5: ultrasound echo signal is depicted as color diagram by host computer, then carries out first arrival detection, is depicted as hole wall figure
Obtain the horizontal distance l of ultrasonic probe four direction to hole wall1i、l2i、l3i、l4i；
Step 6: according to l1i、l2i、l3i、l4iCalculate the average diameter D of stake holes:
Work as l1i≥l2i,l3i≥l4iWhen:
In formula, R1i、R2iFor at pore radius；
Work as l2i≥l1i,l3i≥l4iWhen:
Work as l2i≥l1i,l4i≥l3iWhen:
Work as l1i≥l2i,l4i≥l3iWhen:
Calculate the average diameter of stake holes
Step 7: according to l1、l2、l3、l4Calculate the verticality K of stake holes:
If sonic probe center is X relative to the deviation coordinate of stake holes central point when the 1st measuring point1、Y1, when n-th of measuring point
Sonic probe center is X relative to the deviation coordinate at central point of holen、Yn, then:
X1=l11—(l11+l21)/2
Y1=l31—(l31+l41)/2
Xn=l1n—(l1n+l2n)/2
Yn=l3n—(l3n+l4n)/2
In formula, l11、l21、l31、l41When for the 1st measuring point, center probe in the horizontal direction to 4 directions of hole wall away from
From l1n、l2n、l3n、l4nWhen for n-th of measuring point, center probe is in the horizontal direction to the distance in 4 directions of hole wall；
If eccentricity when n-th of measuring point of stake holes is En, have:
So verticality K of the stake holes in n-th of measuring pointnAre as follows:
In formula, HnFor the hole depth value of n-th of measuring point.
Beneficial effect
A kind of ultrasonic drilled-hole inspecting method based on FPGA proposed by the present invention, has the beneficial effect that:
(1) hardware design that ultrasonic testing system is completed using FPGA is realized to the filtering of signal using built-in IP kernel
Reason, improves the working performance of system.
(2) transmitting and reception set energy converter and realize ultrasonic signal are closed using the transmitting-receiving of 4 tunnels, replace previous bistatic super
Sonic transducer reduces the volume of probe, increases system investigation depth.
Detailed description of the invention
Fig. 1 is ultrasonic drilled-hole inspecting schematic illustration of the invention.
Fig. 2 is orifice size calculation schematic diagram.
Fig. 3 is that verticality calculates schematic diagram.
Fig. 4 is host computer interface schematic diagram of the invention.
Fig. 5 is that ultrasonic transducer probe structure chart is set in transmitting-receiving conjunction.
Fig. 6 is ultrasonic drilled-hole inspecting system principle diagram.
Specific embodiment
Now in conjunction with embodiment, attached drawing, the invention will be further described:
The present invention is completed using 4 road ultrasonic signal of FPGA parallel processing, using built-in IP kernel at the filtering of acquisition signal
Reason, the system one-time detection of may be implemented, which can be obtained, influences hole quality including aperture, hole depth, hole perpendicularity and hole wall situation etc.
Nearly all parameter, detection efficiency is fast, precision is high, have important engineering research meaning.
The present invention is a kind of ultrasonic drilled-hole inspecting method and system based on FPGA.This system specifically divides are as follows: host computer
Module, winch module, signal synthesis processing module, transmitting-receiving, which are closed, sets energy converter array module.
Each module concrete function are as follows:
(1) host computer realizes integrated man-machine's interaction of ultrasonic drilled-hole inspecting system, including detection parameters setting, acquisition number
Show and print according to storage, data analysis, data waveform drawing, pore-forming effect picture etc..
(2) winch is communicated by serial ports with single chip control module, controls the rising of ultrasonic transducer probe under
It puts.
(3) signal synthesis processing module, including two parts of Microcontrollers and FPGAs realize the core of ultrasonic drilled-hole inspecting system
Heart control and signal processing function, including emitting/receiving ultrasonic signal gain control at different depth, with master system
Communication and data transmission etc..Wherein, single-chip microcontroller is mainly responsible for the control function realized to hardware system, this partial function is more simple
It is single, and FPGA is responsible for realizing ultrasonic signal processing function, including sends weak ultrasonic signal, ultrasonic probe to ultrasonic probe
Intense ultrasonic wave signal is converted by weak ultrasonic signal, the signal returned to ultrasonic probe is filtered and transmits, this
Partial processing requirement is higher and the core of whole system.
(4) transmitting-receiving, which is closed, sets transducer array, realizes the transmitting and reception of 4 road ultrasonic signals.
As shown in Figure 1, the present invention is a kind of ultrasonic drilled-hole inspecting method and system based on FPGA, composition includes upper
Machine, winch mechanism, ultrasonic probe three parts.
Supersonic inspection of bored hole system uses ultrasonic reflections technology, and in practice, control winch is by ultrasonic probe along filling
The drill center of full mud is transferred with given pace, in probe decentralization process, every one group (four of certain depth distance measurement
It is a) measuring point sound of the sound duration as the depth when.In this way, strong by record ultrasonic reflections time and reflection from aperture to bottom hole
Degree can calculate the aperture value to drill at different depth and can reflect hole wall situation, and host computer records different depth
The duration of measuring point sound simultaneously calculates the depth aperture.When measuring probe completes primary decline process, host computer can draw measured hole
Hole wall sectional view.When holding suspension centre is constant during promoting probe and wirerope is vertical for winch mechanism, then by being surveyed
The verticality parameter of the available pore-forming of hole wall sectional view in hole.
As shown in Fig. 2, to calculate the schematic diagram in pore-forming aperture.The calculation method in aperture is to be in stake holes based on sonic probe
Heart point position on.But in actual measurement, probe is in most cases to deviate stake holes center, and the aperture measured at this time is cutd open
Face measuring point is not through the diameter in hole, i.e. actual measurement aperture is less than effective aperture, and therefore, it is necessary to be asked by certain calculation method
Obtain effective aperture value.Assuming that having measured the distance value of center probe and 4 direction hole walls in stake holes depth, O is stake holes
Central point, O' point are center probe point.
Work as l1≥l2,l3≥l4When:
In formula, l1、l2、l3、l4For the horizontal distance of probe transducers four direction to hole wall, R1、R2For at pore radius.
Work as l1≥l2,l4≥l3Or when other situations, it is the same with above method can be in the hope of aperture.As long as host computer into
Differentiated when the analysis of row data, it can be in the hope of the average diameter D of stake holes using corresponding formula.
As shown in figure 3, to be calculated as the schematic diagram of hole perpendicularity.For the verticality for calculating pore-forming, hole should be calculated first
The relative deviation of center and ultrasonic probe.O is center probe point, O in figure1For the 1st measuring point stake holes central point, OnIt is n-th
Measuring point stake holes central point.If sonic probe center is X relative to the deviation coordinate of stake holes central point when the 1st measuring point1、Y1, n-th
Sonic probe center is X relative to the deviation coordinate at central point of hole when a measuring pointn、Yn, then:
X1=l11—(l11+l21)/2
Y1=l31—(l31+l41)/2
Xn=l1n—(l1n+l2n)/2
Yn=l3n—(l3n+l4n)/2
In formula, l11、l21、l31、l41When for the 1st measuring point, center probe in the horizontal direction to 4 directions of hole wall away from
From l1n、l2n、l3n、l4nWhen for n-th of measuring point, center probe is in the horizontal direction to the distance in 4 directions of hole wall.
If eccentricity when n-th of measuring point of stake holes is En, have:
So verticality K of the stake holes in n-th of measuring pointnAre as follows:
In formula, HnFor the hole depth value of n-th of measuring point.
As shown in figure 4, host computer mainly realizes the comprehensive of ultrasonic drilled-hole inspecting system using QT software development host computer interface
Close human-computer interaction, including detection parameters setting, acquired data storage, data analysis (calculating of the parameters such as aperture and verticality), number
Show and print according to waveform drawing, pore-forming effect picture etc..Winch is communicated by serial ports with host computer, and winch passes through rope traction
Ultrasonic transducer probe is sent the rising and decentralization of instruction control ultrasonic transducer probe by host computer.
As shown in figure 5, the present invention, which uses ultrasonic probe to close for transmitting-receiving, sets form, two pairs of transducers, two exchanges are arranged altogether
Can device be orthogonal cross installation, the hole wall section of detection drilling both direction.
As shown in fig. 6, signal synthesis processing of the present invention includes two parts of Microcontrollers and FPGAs, ultrasonic drilled-hole inspecting is realized
The core of system control and signal processing function, including different depth at emit/receive ultrasonic signal gain control, with it is upper
The communication of machine system and data transmission etc..Wherein, single-chip microcontroller is mainly responsible for the control function realized to hardware system, this part function
Can be relatively simple, and FPGA is responsible for realizing ultrasonic signal processing function, generation, filtering processing and biography including ultrasonic signal
Defeated, the processing requirement of this part is higher and the core of whole system.
The system is completed using 4 road ultrasonic signal of FPGA parallel processing, using built-in IP kernel at the filtering of acquisition signal
Reason, realizing that system one-time detection can be obtained influences the several of hole quality including aperture, hole depth, hole perpendicularity and hole wall situation etc.
All parameters, detection efficiency is fast, precision is high.And system develops host computer interface using QT, realizes the integrated man-machine of system
Interaction, friendly interface.Research of the invention provides thinking for the exploitation of similar products at home and abroad, facilitates further lifting system
Working performance has important engineering research meaning.
Claims (1)
1. a kind of ultrasonic drilled-hole inspecting method based on FPGA, it is characterised in that steps are as follows:
Step 1: single chip control module and FPGA signal processing module be installed in winch mechanism, single chip control module with it is upper
Position machine, winch mechanism connection, FPGA signal processing module are connect with host computer, ultrasonic probe；
Step 2: host computer sends control winch mechanism signal to single chip control module, adopts to the transmission of FPGA signal processing module
Collect signal, FPGA signal processing module sends ultrasonic signal to ultrasonic probe；
Step 3: winch mechanism transfers ultrasonic probe along drill center with given pace, in ultrasonic probe decentralization process
In, every one group of 4 ultrasound echo signal of certain depth distance measurement；
Step 4: ultrasound echo signal sends host computer to after being filtered by FPGA signal processing module；
Step 5: ultrasound echo signal is depicted as color diagram by host computer, then carries out first arrival detection, is depicted as hole wall figure and is obtained
Ultrasonic probe four direction to hole wall horizontal distance l1i、l2i、l3i、l4i；
Step 6: according to l1i、l2i、l3i、l4iCalculate the average diameter D of stake holes:
Work as l1i≥l2i,l3i≥l4iWhen:
In formula, R1i、R2iFor at pore radius；
Work as l2i≥l1i,l3i≥l4iWhen:
Work as l2i≥l1i,l4i≥l3iWhen:
Work as l1i≥l2i,l4i≥l3iWhen:
Calculate the average diameter of stake holes
Step 7: according to l1、l2、l3、l4Calculate the verticality K of stake holes:
If sonic probe center is X relative to the deviation coordinate of stake holes central point when the 1st measuring point1、Y1, sound wave when n-th of measuring point
Center probe is X relative to the deviation coordinate at central point of holen、Yn, then:
X1=l11—(l11+l21)/2
Y1=l31—(l31+l41)/2
Xn=l1n—(l1n+l2n)/2
Yn=l3n—(l3n+l4n)/2
In formula, l11、l21、l31、l41When for the 1st measuring point, center probe in the horizontal direction to the distance in 4 directions of hole wall,
l1n、l2n、l3n、l4nWhen for n-th of measuring point, center probe is in the horizontal direction to the distance in 4 directions of hole wall；
If eccentricity when n-th of measuring point of stake holes is En, have:
So verticality K of the stake holes in n-th of measuring pointnAre as follows:
In formula, HnFor the hole depth value of n-th of measuring point.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113482536A (en) * | 2021-08-03 | 2021-10-08 | 深圳宏业基岩土科技股份有限公司 | Hole expanding device for intelligently detecting hole diameter of anchor cable hole expanding section |
| CN113529706A (en) * | 2021-08-03 | 2021-10-22 | 深圳宏业基岩土科技股份有限公司 | Anchor cable construction method for intelligently detecting hole expanding aperture |
| CN117168276A (en) * | 2023-11-03 | 2023-12-05 | 北京华力方元科技有限公司 | Quality detection device and method for dry hole of cast-in-place pile |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113482536A (en) * | 2021-08-03 | 2021-10-08 | 深圳宏业基岩土科技股份有限公司 | Hole expanding device for intelligently detecting hole diameter of anchor cable hole expanding section |
| CN113529706A (en) * | 2021-08-03 | 2021-10-22 | 深圳宏业基岩土科技股份有限公司 | Anchor cable construction method for intelligently detecting hole expanding aperture |
| CN113482536B (en) * | 2021-08-03 | 2023-12-08 | 深圳宏业基岩土科技股份有限公司 | Reaming device for intelligently detecting aperture of reaming section of anchor cable hole |
| CN117168276A (en) * | 2023-11-03 | 2023-12-05 | 北京华力方元科技有限公司 | Quality detection device and method for dry hole of cast-in-place pile |
| CN117168276B (en) * | 2023-11-03 | 2024-02-02 | 北京华力方元科技有限公司 | Quality detection device and method for dry hole of cast-in-place pile |
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Inventor after: Wang Yingmin Inventor after: Wang Qi Inventor after: Tao Linwei Inventor after: Zhu Jianchao Inventor after: Xu Peiyuan Inventor before: Zhu Jianchao Inventor before: Wang Qi Inventor before: Wang Yingmin Inventor before: Tao Linwei Inventor before: Xu Peiyuan |
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Application publication date: 20191119 |