CN104407346A - Mobile runway foreign object debris (FOD) monitoring method based on information integration - Google Patents

Abstract

The invention discloses a mobile runway foreign object debris (FOD) monitoring method based on information integration. The method includes the following steps: (1) a millimeter-wave radar conducts successive detections of a set area in front of a vehicle, and each detection includes the processes of millimeter-wave emission and back wave receiving; (2) FOD feature information is extracted from back wave signals for FOD detection, and the position information of suspected FOD is recorded in detail in case the FOD is detected; (3) when the suspected FOD enters a certain range of a moving vehicle, comprehensive judgment is carried out on the information of accumulated times of appearance of the suspected FOD during the multiple detections, the suspected FOD conforming to a certain degree of confidence is submitted to a rear-end camera for identification and confirmation; (4) the camera shoots the suspected FOD to create a clear image of the suspected FOD; (5) the clear image of the suspected FOD is processed to enhance the image features of the suspected FOD; (6) the FOD existence in the image is automatically identified.

Description

A kind of portable runway monitoring foreign bodies method based on information fusion

Technical field

The present invention relates to a kind of portable airfield runway monitoring foreign bodies method based on information fusion; can be applicable to the foreign matter inspection and monitoring to airfield runway, taxiway, hardstand on portable airfield runway foreign body monitoring system; greatly reduce and detect false alarm rate; improve detection efficiency, belong to aeronautic measurement technical field.

Background technology

Airfield runway foreign matter FOD (Foreign Object Debris), refer to any object appearing at improper position in airport, this object can scratch aero tyre, clash into fuel tanker or body, cause overrunning, cause aircraft accident, time serious, jeopardize passenger survival property, cause airliner delay, abort, cause huge economic loss.

At present, substantially also rely on artificial timed patrol both at home and abroad to the detection of FOD, the method not only efficiency is low and unreliable, occupy runway service time, make flight number of times be forced to reduce, and due to human eye vision tired, loss is very high, and aircraft takes off at runway and there is potential danger.At present, carry out both at home and abroad the exploitation of research to FOD detection technique and detection system one after another, just portable detection technique, the airport foreign matter detection system of domestic and international research and development, i.e. portable runway foreign matter detection system, be, at vehicular platform, millimetre-wave radar and video camera be installed, immediately detected by millimetre-wave radar, camera review assists the method for carrying out artificial cognition to detect foreign matter.This method has two relatively outstanding defects: once be millimetre-wave radar scan suspicious foreign matter time instant alarming, like this due to the impact of clutter strongly in millimetre-wave radar echoed signal, easily produce false-alarm; Two is millimetre-wave radar scans suspicious foreign matter instant alarming while, can control video camera and carry out picture catching, and like this if there is false-alarm frequently, frequently will transfer video camera, work efficiency can reduce greatly; Be the mode of employing artificial cognition simultaneously to the image of cameras capture, greatly can reduce detection efficiency equally.Therefore, must have that new method detects immediately to existing millimetre-wave radar, camera review indirect labor knows method for distinguishing and improves, to reduce the false alarm rate of detection, improve the efficiency detected.

Summary of the invention

For the deficiency that prior art exists, the object of the present invention is to provide a kind of portable runway monitoring foreign bodies method based on information fusion, by adopting in the fusion of suspicious foreign matter repeated detection information and the automatic identifying of video camera the fusion adopting radar information and shooting information in radar foreign bodies detection process, jointly complete the detection to foreign matter, false alarm rate in the original detection method of remarkable reduction, improve detection efficiency, mode simultaneously by automatically identifying improves the artificial cognition mode in original detection method, also detection efficiency is substantially increased, improve the utilization factor of airfield runway.

The object of the invention is to be achieved through the following technical solutions:

Based on a portable runway monitoring foreign bodies method for information fusion, comprise following steps:

Step 1), millimetre-wave radar successively detects vehicle front setting regions, each detection comprises millimeter wave and launches and echo receive process;

Step 2), gather for each the echoed signal received, foreign matter characteristic information is extracted to carry out foreign bodies detection from echoed signal, if detect foreign matter, the foreign matter detected is classified as doubtful suspicious foreign matter, records the positional information of this doubtful suspicious foreign matter in detail;

Step 3), when this doubtful suspicious foreign matter position enters in the certain limit of moving vehicle, comprehensive distinguishing is carried out to this doubtful suspicious foreign matter accumulation occurrence number information in repeatedly detection process, submits to rear end video camera to carry out recognition and verification as suspicious foreign matter the doubtful suspicious foreign matter meeting confidence degree;

Step 4), video camera makes a video recording to suspicious foreign matter, forms the picture rich in detail of suspicious foreign matter;

Step 5) characteristics of image that image procossing strengthens suspicious foreign matter is carried out to the picture rich in detail of suspicious foreign matter;

Step 6) automatically whether there is foreign matter in recognition image.

According to above-mentioned feature, described step 2) in from echoed signal, extract foreign matter characteristic information comprise following steps to carry out foreign bodies detection:

Step 2.1) resolution sampling is carried out to the millimeter wave echoed signal received, be converted to digital signal;

Step 2.2), adopt filtering mode suppress conversion after echo digital signal in land clutter signal amplitude;

Step 2.3), adopt one dimension Fast Fourier Transform (FFT), echo digital signal is converted to frequency domain by time domain;

Step 2.4), adopt constant false alarm rate algorithm to carry out amplitude differentiation to the echo digital signal being converted to frequency domain, detect whether there is doubtful suspicious foreign matter.

According to above-mentioned feature, described step 3) in the computing method of degree of confidence be:

If doubtful suspicious foreign matter experiences the radar scanning of N submillimeter wave altogether, the result that each scanning detects is T [i] (i=1 ~ N), if this doubtful suspicious foreign matter does not detect this scanning, then and T [i]=0, if detect, then T [i]=1; Set again each testing result weight as a [i] (i=1 ~ N), according to distance, a [i] arranges from small to large, and the cumulative sum of N number of a [i] is 1; If the degree of confidence that doubtful suspicious foreign matter exists is β, then β computing formula is:

$\mathrm{\β}=\underset{i=1}{\overset{N}{\mathrm{\Σ}}}T\left[i\right]\·\mathrm{\α}\left[i\right].$

According to above-mentioned feature, described step 4) in carry out aiming at centered by suspicious foreign matter by controlling video camera by the positional information of suspicious foreign matter, focus, imaging operation, form the picture rich in detail in suspicious foreign matter region.

According to above-mentioned feature, described step 5) in image procossing comprise image filtering, image enhancement operation.

According to above-mentioned feature, described step 6) in automatically in recognition image whether exist foreign matter according to the edge contour for doubtful suspicious foreign matter.

The one portable runway monitoring foreign bodies method of the present invention's invention, by adopting in the fusion of repeated detection information before and after doubtful suspicious foreign matter and the automatic identifying of video camera the fusion adopting radar information and shooting information in radar foreign bodies detection process, jointly complete the detection to foreign matter, false alarm rate in the original detection method of remarkable reduction, improve detection efficiency, mode simultaneously by automatically identifying improves the artificial cognition mode in original detection method, also substantially increase detection efficiency, improve the utilization factor of airfield runway.

Accompanying drawing explanation

The brief outline of procedure figure of Fig. 1 detection method.

Fig. 2 radar foreign bodies detection of the present invention schematic diagram.

The detailed diagram of Fig. 3 radar foreign bodies detection of the present invention process.

Label declaration in figure

1-radar scanning

2-single detects

3-repeatedly differentiate

4-shooting catches

5-image procossing

6-automatically identify

7-mobile platform

8-scanning beam

9-pixel

10-doubtful suspicious foreign matter

11-echo signal sample

12-ground bounce removal

13-frequency spectrum calculates

14-constant false alarm rate detects

15-position is followed the tracks of

16-confidence calculations

17-foreign matter differentiates

Embodiment

Below in conjunction with accompanying drawing 1-Fig. 3, further illustrate the present invention and how to realize.

A kind of portable runway monitoring foreign bodies method based on information fusion of the present invention, consists predominantly of millimetre-wave radar foreign matter detecting method and the automatic method for recognizing impurities of video camera.As shown in Figure 1, Figure 3, millimetre-wave radar foreign matter detecting method comprises the step such as radar scanning 1, single detection 2, repeatedly differentiation 3, described radar scanning 1 forms foreign matter echo information, described single detects 2 pairs of foreign matter echo information and analyzes, obtain single and detect certain suspicious foreign matter positional information, described repeatedly differentiation 3 pairs of singles detect certain suspicious foreign matter positional information and carry out information accumulation, arrive in distance mobile platform certain limit at certain doubtful suspicious foreign matter, comprehensively analyze certain doubtful suspicious foreign substance information of accumulation, whether final differentiation is suspicious foreign matter.

Below in conjunction with Fig. 2, the principle of millimetre-wave radar foreign matter detecting method is further described.

As shown in Figure 2, mobile platform 7 top is provided with millimetre-wave radar and video camera, described mobile platform 7 is advanced along runway axis by certain speed V, in traveling process, the described scanning beam 8 of millimetre-wave radar (is generally the longitudinal 20m ~ 200m of vehicle front by electric scanning or mechanical scanning to setting regions, horizontal 60m) carry out continual continuous sweep, setting regions single pass is made up of some pixel 9 scanning, each described pixel 9 scanning comprises a submillimeter wave and launches and echo receive process, gather the echoed signal received, carry out filtering process and spectrum analysis, from echoed signal, extract foreign matter characteristic information by specific algorithm and carry out foreign bodies detection, what detect is doubtful suspicious foreign matter 10, the detailed record of positional information is carried out to described doubtful suspicious foreign matter 10, then in follow-up each scanning process, whether this doubtful suspicious foreign matter is detected again and carries out detailed record, until within the scope of this doubtful suspicious foreign matter is apart from 20 meters of described mobile platform 7 time, again comprehensive distinguishing is carried out to information such as the number of times that this doubtful suspicious foreign matter occurs, to be determined as suspicious foreign matter submits to rear end video camera to carry out recognition and verification.Generalized case, doubtful suspicious foreign matter from first time scanning discovery within the scope of 20 meters that appear at described mobile platform 7, millimetre-wave radar can scan several times, and (requirement is greater than 10, concrete according to millimetre-wave radar sweep speed and determine), the simplest method of discrimination is if the number of times that this doubtful suspicious foreign matter occurs is greater than certain number, can be determined as suspicious foreign matter.

Described single detects 2 and comprises the steps such as echo signal sample 11, ground bounce removal 12, frequency spectrum calculating 13, constant false alarm rate detection 14.

Described echo signal sample 11, for carrying out high speed, high resolving power sampling to the millimeter wave echoed signal received, is converted to digital signal;

Described ground bounce removal 12, the land clutter signal amplitude in the echo digital signal after adopting the modes such as filtering to suppress conversion, improves the signal to noise ratio (S/N ratio) of signal;

Described frequency spectrum calculates 13, adopts one dimension Fast Fourier Transform (FFT), echo digital signal is converted to frequency domain by time domain;

Described constant false alarm rate detects 14, adopts constant false alarm rate algorithm to carry out amplitude differentiation to the echo digital signal being converted to frequency domain, detects whether this pixel exists doubtful suspicious foreign matter, and the information such as the doubtful suspicious foreign matter position of record judgement.

Described repeatedly differentiation 3 comprises the steps such as position tracking 15, confidence calculations 16, foreign matter differentiation 17.

Whether described position follows the tracks of 15, follows the tracks of after scanning to the doubtful suspicious foreign matter position detected at every turn, monitor and have doubtful suspicious foreign matter to enter within the scope of 20 meters of described mobile platform 7, to start follow-up confidence calculations and foreign matter differentiation.

Described confidence calculations 16, for strengthening closely, testing result is on the impact of whole differentiation result, and because the distance of millimetre-wave radar detection is shorter, pitching degree is larger, the echo that foreign matter is formed is stronger, the probability that foreign matter is detected is larger, and testing result confidence level is higher, therefore, different weights is distributed by the distance of foreign matter distance millimetre-wave radar, foreign matter from millimetre-wave radar more away from, this time testing result weight is less, otherwise larger.If certain doubtful suspicious foreign matter experiences N scanning altogether, scan the result detected is T [i] (i=1 ~ N) at every turn, if this doubtful suspicious foreign matter does not detect this scanning, then and T [i]=0, if detect, then T [i]=1; Set again each testing result weight as a [i] (i=1 ~ N), according to distance, a [i] arranges from small to large, and the cumulative sum of N number of a [i] is 1; If the degree of confidence that doubtful suspicious foreign matter exists is β, then β computing formula is:

$\mathrm{\β}=\underset{i=1}{\overset{N}{\mathrm{\Σ}}}T\left[i\right]\·\mathrm{\α}\left[i\right].$

Described foreign matter differentiates 17, for weighing the result of calculation β in described confidence calculations, if β >=M (M numerical value can adjust according to actual conditions, general span: 0.7≤M≤1.0), then judge that doubtful suspicious foreign matter is as suspicious foreign matter for this reason; If β≤M, then judge that doubtful suspicious foreign matter does not exist for this reason.

Below according to Fig. 1, further illustrate the automatic method for recognizing impurities of video camera, comprise the step such as shooting seizure 4, image procossing 5, automatically identification 6.

The suspicious foreign matter that described shooting seizure 4 pairs of millimetre-wave radars detect is made a video recording, and is controlled the operations such as video camera carries out aiming at, focuses centered by suspicious foreign matter, imaging, form the picture rich in detail in suspicious foreign matter region by the positional information of this suspicious foreign matter.

Described image procossing 5 carries out image procossing to the picture rich in detail that described shooting seizure 4 is formed, and comprises the operation such as image filtering, image enhaucament, reduces external environmental interference or noise, strengthens the characteristics of image of suspicious foreign matter.

Described automatic identification 6 carries out Image Edge-Detection to the picture rich in detail containing suspicious foreign matter target signature that described image procossing 5 is formed.If this suspicious foreign matter necessary being, then can form the edge contour of this suspicious foreign matter by detection algorithm, and identification is reported to the police automatically; If this suspicious foreign matter does not exist, then cannot form rational edge contour by detection algorithm, be judged as false-alarm.

The one portable runway monitoring foreign bodies method of the present invention's invention, by the fusion of twice different information, one is use in radar foreign bodies detection process, time series merges the information of repeated detection before and after doubtful suspicious foreign matter, determines suspicious foreign matter; Two is use in the automatic identifying of video camera, the image information that the suspicious foreign substance information judge radar and video camera are taken merges, determine foreign matter, the detection to foreign matter is jointly completed by twice different level, different classes of information fusion, false alarm rate in the original detection method of so remarkable reduction, improve detection efficiency, mode simultaneously by automatically identifying improves the artificial cognition mode in original detection method, also substantially increase detection efficiency, improve the utilization factor of airfield runway.

Claims (6)

1., based on a portable runway monitoring foreign bodies method for information fusion, comprise following steps:

Step 1), millimetre-wave radar successively detects vehicle front setting regions, each detection comprises millimeter wave and launches and echo receive process;

Step 2), gather for each the echoed signal received, foreign matter characteristic information is extracted to carry out foreign bodies detection from echoed signal, if detect foreign matter, the foreign matter detected is classified as doubtful suspicious foreign matter, records the positional information of this doubtful suspicious foreign matter in detail;

Step 3), when this doubtful suspicious foreign matter position enters in the certain limit of moving vehicle, comprehensive distinguishing is carried out to this doubtful suspicious foreign matter accumulation occurrence number information in repeatedly detection process, submits to rear end video camera to carry out recognition and verification as suspicious foreign matter the doubtful suspicious foreign matter meeting confidence degree;

Step 4), video camera makes a video recording to suspicious foreign matter, forms the picture rich in detail of suspicious foreign matter;

Step 5) characteristics of image that image procossing strengthens suspicious foreign matter is carried out to the picture rich in detail of suspicious foreign matter;

Step 6) automatically whether there is foreign matter in recognition image.

2. portable runway monitoring foreign bodies method according to claim 1, is characterized in that described step 2) in from echoed signal, extract foreign matter characteristic information comprise following steps to carry out foreign bodies detection:

Step 2.1) resolution sampling is carried out to the millimeter wave echoed signal received, be converted to digital signal;

Step 2.2), adopt filtering mode suppress conversion after echo digital signal in land clutter signal amplitude;

Step 2.3), adopt one dimension Fast Fourier Transform (FFT), echo digital signal is converted to frequency domain by time domain;

Step 2.4), adopt constant false alarm rate algorithm to carry out amplitude differentiation to the echo digital signal being converted to frequency domain, detect whether there is doubtful suspicious foreign matter.

3. portable runway monitoring foreign bodies method according to claim 1, its feature is in described step 3) in the computing method of degree of confidence be:

If doubtful suspicious foreign matter experiences the radar scanning of N submillimeter wave altogether, the result that each scanning detects is T [i] (i=1 ~ N), if this doubtful suspicious foreign matter does not detect this scanning, then and T [i]=0, if detect, then T [i]=1; Set again each testing result weight as a [i] (i=1 ~ N), according to distance, a [i] arranges from small to large, and the cumulative sum of N number of a [i] is 1; If the degree of confidence that doubtful suspicious foreign matter exists is β, then β computing formula is:

$\mathrm{\β}=\underset{i=1}{\overset{N}{\mathrm{\Σ}}}T\left[i\right]\·a\left[i\right].$

4. portable runway monitoring foreign bodies method according to claim 1, it is characterized in that in described step 4) in carry out aiming at centered by doubtful suspicious foreign matter by controlling video camera by the positional information of suspicious foreign matter, focus, imaging operation, form the picture rich in detail in suspicious foreign matter region.

5. portable runway monitoring foreign bodies method according to claim 1, is characterized in that in described step 5) in image procossing comprise image filtering, image enhancement operation.

6. portable runway monitoring foreign bodies method according to claim 1, is characterized in that in described step 6) in automatically whether exist in recognition image foreign matter according to the edge contour for suspicious foreign matter.