Vehicle equipped with system for detecting foreign objects or fragments, unevenness or cracks on runway

Abstract

The invention describes a vehicle (1) of the aircraft, unmanned aerial system (UAS) or drone type equipped with a system for detecting foreign objects or debris (FOD) (7), road irregularities or cracks on a runway (3). The system comprises a broadband frequency modulated radar (5) with a center frequency > 20 GHz, generating high resolution images (9) by synthetic aperture radar (SAR) processing techniques to identify foreign matter, debris (7), irregularities or cracks on the runway surface. The vehicle (1) can be moved along the runway (3) to optimize image acquisition at a glancing perspective and low altitude flight.

Description

Technical Field

[0001] The present invention relates to an aircraft, unmanned aerial system ("UAS") or drone type vehicle equipped with an onboard system for identifying foreign objects or debris (FOD), road surface irregularities or cracks on a runway, in particular an airport runway or a car / motorcycle racing track. Background Art

[0002] It is known that the detection of foreign objects or debris (FOD) and pavement irregularities or cracks on runways, especially airport runways, is an extremely serious problem (especially after the Concorde crash in July 2000).

[0003] However, currently there is no effective technology that can reliably, accurately and near real-time identify such foreign objects or debris other than manual visual inspection, which is extremely inefficient if performed by an operator.

[0004] In the existing technology, solutions using cameras, laser radar (LIDAR) and professional image recognition systems require high computing costs and the results are not satisfactory.

[0005] Another known solution uses synthetic aperture radar (GBSAR, ground-based synthetic aperture radar) to observe the runway surface at a grazing angle, but it requires fixed installation equipment and can only cover a partial area of ​​the runway. If the entire runway is required, a large number of equipment must be deployed, resulting in a significant increase in cost and computation. In addition, the imaging resolution of this solution is uneven and is limited by distance and viewing angle, making it difficult to identify small objects on a large runway.

[0006] Other proposals have proposed using remotely piloted aircraft (UAS) or drones for airport security inspections and foreign object detection. Some can even generate orthophotos for inspecting airport runways, but none of them combine synthetic aperture radar (SAR) technology, and the performance is still not ideal.

[0007] Documents CN-A-109 188 437, CN-A-113 447 926, CN-A-111 538 002, CN-A-113 406639 and John Spriggs's "Runway Safety: Debris Detection Technology" (IIR Runway Safety Conference, October 25, 2001, XP002230491) describe prior art solutions. Summary of the invention

[0008] Therefore, the object of the present invention is to solve the above technical problems and provide an aircraft, UAS or drone type vehicle, which is equipped with an onboard system of synthetic aperture radar (SAR) processing technology for acquiring runway images, thereby achieving better performance than the existing technology in terms of foreign objects, debris or pavement cracks detection.

[0009] The present invention and other objects and advantages (of the vehicle type as claimed in claim 1) will be clarified from the following description and can be achieved by the vehicle described in claim 1.

[0010] Preferred embodiments and non-obvious variants of the invention form the subject matter of the dependent claims.

[0011] It should be understood that all the appended claims constitute an integral part of this description.

[0012] It is obviously understandable that numerous changes and modifications may be made to the content described without departing from the scope of the invention as defined in the appended claims (for example, in terms of shape, size, layout and parts with equivalent functions).

[0013] The invention will be explained more clearly by referring to several preferred embodiments (provided by way of non-limiting examples) of the accompanying drawings, in which: - Figure 1 A front view of a preferred embodiment of the vehicle of the present invention is shown; - Figure 2 A schematic diagram of the operating principle of the vehicle and system of the present invention; - Figure 3a , 3b and 3c are schematic diagrams of examples of use of the vehicle and system of the present invention; - Figure 4 and Figure 5 The following are diagrams related to field use tests of the vehicle and system of the present invention.

[0014] For the sake of brevity, the description of other common parts of the prior art systems and vehicles and their necessary components for basic operation will be omitted below. The relevant technology is common knowledge to those skilled in the art, and the subsequent description will focus on the aspects and components that constitute the system and vehicle characteristics of the present invention.

[0015] Therefore, with reference to the accompanying drawings, a preferred embodiment of a vehicle 1 is shown, which includes an aircraft, an unmanned aerial system UAS or a drone, which is equipped with a system according to the present invention for identifying foreign object debris (FOD) 7, road surface discontinuities or cracks on a runway 3, in particular an airport runway or a motor racing track.

[0016] The system includes at least one wideband frequency modulated radar 5 with a center frequency > 20 GHz, which is designed to acquire images of the runway 3 and provide at least one high-resolution image 9 (i.e., an image having a long side of at least 1920 pixels and a pixel density of at least 300 pixels per inch (ppi), where 1 inch = 25.4 mm) by subjecting such images to synthetic aperture radar ("SAR") processing techniques to locate foreign debris 7, discontinuities or cracks present on the surface of the runway 3.

[0017] The inventive vehicle 1 equipped with the above-described system is designed to move along a runway 3 .

[0018] Advantageously, the vehicle 1 can be driven automatically, semi-automatically, remotely or manually without restriction.

[0019] Similarly, the vehicle 1 may be equipped with an autonomous propulsion device (eg, a land engine and its corresponding transmission system, one or more aircraft engines 6 , etc.).

[0020] Preferably, the above-mentioned frequency is substantially equal to 77 GHz.

[0021] Preferably, the vehicle 1 moves substantially at low altitude (no more than 5 meters from the ground) and at a grazing angle along a lateral trajectory XX substantially parallel to the runway 3 , so that the FM radar 5 can acquire one or more images of the surface of the runway 3 .

[0022] Special reference Figure 2 , the movement of the vehicle 1 in the lateral XX direction along the runway 3 can be observed, and a synthetic aperture is formed by the FM radar 5 and the "SAR" processing technology to obtain an image 9 of the surface area of ​​the detected runway 3: Preferably, the image 9 can also be obtained by incoherent superposition of images previously acquired by the FM radar 5 to compensate for possible trajectory deviations when the vehicle 1 moves along the runway 3.

[0023] The vehicle 1 may also include means 8 for processing and feeding artificial intelligence applications and devices, for example of the type based on the NVIDIA® Jetson NANO™ platform.

[0024] In particular, Figure 3a , 3b and 3 c show in schematic form an airport runway 3 along which the vehicle 1 moves at low altitude to the side to acquire an image 9 of the surface of the runway 3 (in the presence of debris 7 ), a plan view of the runway 3 ( Figure 3b ), and the same runway 3 image 9 obtained by "SAR" processing technology ( Figure 3c ), where clasts7 are clearly identified and highlighted.

[0025] Figure 4 and 5Also shown are the results of field tests of a vehicle 1 according to the present invention on a straight runway 3, on which discontinuities or breaks, two cars and a plurality of corner reflectors are arranged as targets for foreign object debris (FOD) to be identified in the pavement: therefore, in these examples of graphs, the left vertical axis y and the horizontal axis x represent the longitudinal and lateral distances of the runway 3, respectively, and the right vertical axis A represents the amplitude measurement value, showing the surface image 9 of the runway 3 obtained by the system of the present invention when the vehicle 1 moves along the runway 3 in the above-mentioned moving manner, in which the targets (two cars 13a and 13b and the reflector 15) are clearly shown.

[0026] Compared with the existing technical solutions, installing the radar on the above-mentioned vehicle has a significant advantage: it can scan the entire length of the runway 3 while maintaining a uniform resolution of the image 9 (achieved through SAR processing).

[0027] Compared with the existing technical solutions, the vehicle of the present invention can also achieve the following technical advantages: - Using a wideband frequency modulated radar with a center frequency of >20 GHz5, which can ensure a good signal-to-noise ratio even for tiny debris or discontinuities (down to the millimeter level); - The solution of the vehicle 1 moving along the runway 3 with a grazing angle of view avoids ground reflections, thus ensuring that the signal only originates from small surface discontinuities; this grazing angle of view also maximizes the resolution of the FM radar 5 in the detection direction; - Using the "SAR" processing technology, it is possible to obtain detection results with very high resolution (theoretically up to millimeter level) by using the movement of the vehicle 1 orthogonal to the detection direction of the runway 3; - "SAR" processing technology with compensation function for the non-perfectly straight trajectory of vehicle 1 can also be considered; - Further consideration is given to using a two-step SAR processing technique (coherent stacking and incoherent stacking), which is highly robust to the compensation errors of non-perfectly straight trajectories and does not require reliance on computationally intensive autofocus technology; - By acquiring radar images 9 on both sides of the runway 3 and processing them based on the same coordinate grid, it is possible to accurately identify foreign object debris (FOD) 7, discontinuities or breaks in the pavement, whose shape characteristics are difficult to identify in a single-sided observation.

Claims

1. An aircraft, unmanned aerial system (UAS) or drone type vehicle (1) equipped with a system for identifying foreign objects or debris (FOD) (7), unevenness or cracks on a runway (3), the system comprising at least one wideband frequency modulated radar (5) with a center frequency > 20 GHz, for acquiring images of the runway (3) and generating at least one high-resolution image (9) by synthetic aperture radar (SAR) processing technology, the longest side of the image being at least 1920 pixels and a density of at least 300 pixels per inch (ppi), where 1 inch = 25.4 mm, to locate foreign objects, debris (7), unevenness or cracks on the runway surface; the vehicle (1) being movable along the runway (3).

2. The vehicle (1) according to claim 1, characterized in that: The vehicle (1) is driven automatically, semi-automatically, remotely or manually.

3. The vehicle (1) according to any one of claims 1 to 2, characterized in that: The vehicle (1) is equipped with an autonomous propulsion device (6).

4. The vehicle (1) according to any one of claims 1 to 3, characterized in that: The center frequency is 77 GHz.

5. The vehicle (1) according to any one of claims 1 to 4, characterized in that: The vehicle (1) moves at a height of less than 5 meters, a grazing angle of view, and a lateral trajectory parallel to the runway (3), so that the frequency modulated radar (5) acquires an image of the runway surface orthogonally.

6. The vehicle (1) according to any one of claims 1 to 5, characterized in that: The vehicle (1) comprises a processor (8) for running an AI application.

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