Camera-based detection system

Abstract

A goal detection system (1) comprises a camera housing (6) having a tubular casing (7) for containing a detection camera (8) and a bracket (9) pivotally mounted on one end of the tubular casing (7).

Description

[0001] CAMERA DETECTION SYSTEM

[0002] Technical field

[0003] The present invention relates to the field of technologies intended for detecting the crossing of a goal line. These technologies are commonly referred to by the English term "goal line technology". They are intended to assist the referee in determining whether, with certainty, a ball has completely crossed the goal line. These technologies are intended for use in ball sports, such as football or handball.

[0004] State of the art

[0005] Technologies currently exist for detecting the crossing of a goal line. Stereovision or stereoscopic measurement is known, which involves detecting the ball using a plurality of high-speed video cameras capturing images of the goal cages on each side of the field. The cameras are connected to a central computer that continuously determines the position of the ball. If the ball completely crosses the goal line, the central computer transmits a signal to a device worn by the referee, for example in the form of a watch, which then emits an audible signal. The referee can then immediately validate the goal.With these solutions known from the prior art, the positioning of the cameras is a difficult task and they most often risk being damaged during a football match, in particular when they are positioned in the goal posts, as is the case with the camera system described in application WO2013083112.

[0006] It is also known to create a special magnetic field at the goal, on either side, or on each side of the goal line by burying electrical wires carrying current in this area of ​​the playing field and equipping the ball with a sensor designed to measure this magnetic field. The ball's sensor measures the magnetic field, particularly when the ball enters the goal area, and sends data relating to this measurement to a central computer. The latter then determines from this data whether or not the ball has crossed the goal line. If so, the central computer transmits a signal to a device worn by the referee, which then emits an audible signal.

[0007] It is also known to use LIDAR to detect the crossing of a goal line, however such a system described in application FR3067126 does not allow the shape of the object to be recognized and to be able to determine with certainty that it has a goal only when it is a ball of a chosen size that crosses said line. However, the use of LIDAR has the disadvantage of having to considerably modify the ground and having to dig trenches to bury them there.

[0008] Summary of the invention

[0009] The invention aims to provide an inexpensive alternative technology that is also affordable for the amateur world.

[0010] The invention also aims to propose a system requiring no modification of the goal cage, and more particularly which is suitable for integration directly into the goal cage.

[0011] Another object of the invention is to propose a system that does not require any installation of additional equipment in the playing area or any substantial modification thereof. Indeed, to be compatible with standards such as those established by the IFAB®, and in particular the Laws of the Game 2022 / 23, it is required that the playing area on the ground is not modified, and it is therefore preferable not to modify the ground, for example by digging trenches to insert elements or by placing such elements directly on the ground.

[0012] Another object of the invention is to provide a system which is insensitive to climatic conditions, to the lighting conditions of the playing field or to the color of the ball.

[0013] Another object of the invention is to provide a system which is capable of selectively detecting a full or partial crossing of the goal line and which is therefore applicable to ball sports such as football or handball (in which the goal is only validated if the ball has fully crossed the goal line) or other sports requiring only a partial crossing of the goal line.

[0014] Another objective of the invention is to be able to integrate a detection system into the net lifting system of a goal and to allow the equipment of current football goals without having to completely replace them, that is to say by leaving the posts and the crossbar intact.

[0015] More particularly, the invention relates to a goal detection system comprising a camera housing comprising a tubular casing intended to contain a detection camera and a bracket preferably pivotally mounted on one end of said tubular casing. Preferably, the tubular casing comprises a detection camera.

[0016] Such a configuration of the device according to the present invention makes it possible to easily integrate a camera into a net lifting system for a goal, in particular a football goal, and to be able to position the camera as close as possible to at least one of the two goal posts which support the crossbar.

[0017] The bracket allows for simplified mounting of the detection system at the foot of a goal post by being integrated into the goal net lifting system.

[0018] The term "net lifting system" in the context of the invention describes the holding elements which allow the net of the goal cage to be stretched, and relates in particular to the tubes, some of which are positioned on the ground behind the goal posts and which stretch the net behind the goal line. It is recalled that, conventionally, a goal cage comprises two side posts which are erected vertically on either side of the goal line, and which support a crossbar, the set of the two side posts and the crossbar forming the entrance to the goal cage. This entrance to the goal cage opens onto the net placed behind and which closes the space of said cage.

[0019] The detection system according to the invention makes it possible to easily route information by wire behind the goal cage, via the net lifting system, which allows for fully integrated analysis behind the goal cage and avoids having to set up a complex communication network around the playing field, as is the case with prior art detection systems.

[0020] Preferably, the goal detection system according to the invention comprises a connector designed to be connected to the detection camera comprising cables capable of being integrated into the net lifting device of a football or handball goal, and a box comprising a data processing unit and a wireless communication system, preferably according to the Wifi communication protocol.

[0021] More preferably, said goal detection system comprises two camera housings each having a detection camera, which housings are mounted behind a goal line, i.e. on the ground in the goal cage, and at the foot of each side post, in a configuration where the lenses of the cameras point opposite each other parallel to the axis of the goal line YY', and in a direction ZZ' distant from 0 to 22 cm from the axis of the goal line YY', preferably from 5 to 17 cm, advantageously from 7 to 15 cm, or even from 9 to 13 cm. The inventors have demonstrated that such positioning and dimensioning of the system makes it possible to obtain the best results in terms of detecting a football at the moment it enters the goal cage. Preferably, the field of vision of the cameras is between 100 and 130°.

[0022] Preferably, the goal detection system according to the present invention comprises two electronic cards, an output PCB connected to the tubular formwork, and a connection PCB intended to be connected to the camera. The presence of such electronic cards facilitates the internal connection to the tubular formwork, to comply with the maximum dimensions authorized by the standards at the level of the net recovery system.

[0023] The present invention also relates to a net lifting device comprising a goal net, a first and a second bar for fixing the goal net to the ground and a detection system as presented previously within the scope of the invention, the camera housings being integrated into the bars for fixing the net to the ground. The goal net extends from the opening provided between the posts and the crossbar, behind the goal line at the foot of said posts.

[0024] Preferably, the first and second ground fixing bars of the goal net comprise standby tubes mounted in place of said camera housings. In this configuration, standby tubes are positioned in place of the goal detection systems, which makes it possible to play without equipping the goals with cameras and thus not risk damaging them when their use is not necessary.

[0025] Preferably, two bent tubes and a rear tube, connected perpendicularly to the first and second ground fixing bars by the two bent tubes, are integrated into the net lifting device according to the invention. This makes it possible to have a continuous tubular network in connection with the camera detection system, or the waiting tubes, and to be able to efficiently tension the net and / or guide cables for a wired connection to an image processing unit at the rear of the football goal.

[0026] Preferably, the net lifting device according to the invention comprises at least one rear connector, and the rear tube is made of at least two removable tube parts connected by at least one rear connector. Such a configuration is advantageous since it promotes the exit of the cables from the net lifting device to a processing unit. The present invention also relates to a goal cage comprising two side posts, a crossbar fixed to the two posts at each of its ends, a net, and a net lifting device according to the present invention, for stretching the net integrated in said lifting device behind the goal line while making it possible to control the scoring of goals in the cage during a match.

[0027] The present invention also relates to an image processing method implementing the goal detection system according to the present invention comprising a camera, comprising the steps of:

[0028] - capture of images taken at goal level by the camera;

[0029] - analysis by the continuous data processing unit to detect a ball and

[0030] - the implementation of an algorithm to determine whether the ball has crossed the goal line.

[0031] Other characteristics and advantages may still appear to those skilled in the art upon reading the embodiments below, illustrated by the appended figures, given for illustrative purposes.

[0032] Brief description of the figures

[0033] - Figure 1a is a perspective view of a goal cage equipped with the goal detection system according to the invention;

[0034] - Figure 1 b represents a top view of the goal cage without the net and with only the lower part of the net lifting device, equipped with the goal detection system according to the invention;

[0035] - Figure 2 represents an exploded view of a camera housing of the goal detection system according to the invention;

[0036] - Figure 3 is a perspective view of the goal detection system according to the invention with the camera housing and with its bracket for fixing it to a side (goal) post, and which is connected to a ground fixing bar of the net lifting device;

[0037] - Figure 4 is a schematic view from above of the goal detection system according to the invention integrated into a goal cage; - Figure 5 represents a schematic view of the same mode as that shown in Figure 4, but seen from the front of the goal cage, and an inset shows a detail of the system looking to the side into the goal cage and towards the base of one of the two side posts of the cage.

[0038] Detailed description of the invention

[0039] The invention will be more particularly described in the context of football without any limitation of the scope of the patent to this sport being seen.

[0040] According to the invention, it is proposed to detect the crossing of the goal line of a goal cage by means of one or more cameras associated with each other in an advantageous embodiment, where the optical axes of the cameras are coincident. Conventionally, a football goal cage comprises an assembly consisting of two side posts and the crossbar on which it rests, and which extends vertically above the goal line.

[0041] Figure 1 shows an overall perspective and exploded view of a goal detection system 1 according to the invention which is to be mounted on a football pitch in a goal cage 2 equipped with a net 3. The goal cage 2 also comprises two side posts 4a and 4b and a crossbar 5 supported by the two posts.

[0042] The goal detection system 1 comprises a camera housing 6 comprising a tubular casing 7 intended to contain a detection camera 8 and a bracket 9 pivotally mounted on one end of said tubular casing.

[0043] The tubular formwork 7 may be composed of a tubular casing 7a and a facade 7b mounted by riveting on the casing and having a recess 10 provided for the passage of the lens of the detection camera 8.

[0044] The detection system 1 also comprises a connection consisting of an electrical cable or for the transfer of computer data by wire. The cables are integrated into a net lifting device 11 of a goal cage. The detection system 1 also comprises a housing 12 comprising a data processing unit 13 and possibly a wireless communication system (see Figure 4). In a preferred embodiment, the detection system 1 comprises two camera housings 6a and 6b, each integrating a detection camera 8 in accordance with the above. The two camera housings 6a and 6b are placed such that the cameras are facing each other just behind the goal line.More particularly, the two camera housings 6a and 6b are placed in the net lifting device 11 comprising the net 3 of the goal cage, and are an integral part of ground fixing bars 16 and 17 of the net lifting device 11, being placed just behind the side posts 4a and 4b of the goal.

[0045] More advantageously, the camera housings 6a and 6b are mounted behind a goal line YY' at the feet of each side post 4a and 4b, in a configuration where the camera lenses point opposite each other parallel to the axis of the goal line YY', and in a direction ZZ' distant from 0 to 22 cm, or even 5 to 17 cm, and in particular 11 cm, from the axis of the goal line YY'.

[0046] Standby tubes are used to replace the 6a and 6b camera housings to prevent them from being damaged between matches.

[0047] In a preferred embodiment, the net lifting device 11 comprises three tubular ground parts, containing the ground fixing bars 16 and 17 integrating the camera housings 6a and 6b and a rear tube 18 joined to the two ground fixing bars 16 and 17 by bent tubes 19a and 19b. The rear tube 18 is in two removable tube parts connected by at least one rear connector 20. Such a configuration facilitates the assembly of the net lifting device and makes it easy to pass the cable bundles and / or electrical wires for the connection connecting the camera to a processing unit. According to a preferred embodiment shown in Figure 2, the camera housing 6 comprises the tubular formwork 7 comprising: the tubular casing 7a on which the front 7b is mounted by screwing with four rivets; and a tubular casing cap 21 for laterally closing the formwork.The front 7b includes the recess 10 provided for the passage of the lens of a camera, and an O-ring 22 which ensures the seal at the recess. Two electronic cards, one of which called output PCB 23 is attached to the cap of the tubular casing 21. The other electronic card is a connection PCB 24 to the camera. The two PCB cards 23 and 24 are connected by a ribbon cable, which includes a set of fine cables and which are arranged on the same plane, presenting the desired finesse for connection in small spaces.

[0048] According to a particularly advantageous embodiment, the goal detection system 1 comprises two camera boxes 6a and 6b each equipped with a detection camera 8; and a connector is connected to each detection camera 8. This connector comprises cables integrated into the net lifting device 11 of a football or handball goal 1. The goal detection system 1 also comprises the box 12 comprising the data processing unit 13 and a wireless communication system according to the standard Wifi® communication protocol. According to an advantageous embodiment, the box also integrates a detection camera.

[0049] In this goal detection system, the camera positioning devices 1 are mounted in the goal cage 2 and just behind the goal line, more particularly at the foot of each side post 4a and 4b, in a configuration where the camera lenses point opposite each other parallel to the axis of the goal line YY', and in a direction ZZ' 11 cm from the axis of the goal line YY'. The field of vision of the cameras is 115° (see Figures 4 and 5). The goal detection system is shown in Figure 5 integrated in a football goal cage 2 comprising a first side post 4a, a second side post 4b and the crossbar 5, as well as the ground fixing bars 16 or 17 integrating the camera housings 6a or 6b.

[0050] The invention is described in the foregoing by way of example. It is understood that the person skilled in the art is able to carry out different variant embodiments of the invention, for example by combining the different characteristics above taken alone or in combination, without departing from the scope of the invention.

Claims

DEMANDS 1. Goal detection system (1) comprising a camera housing (6) having a tubular casing (7) intended to contain a detection camera (8) and a bracket (9) pivotally mounted on one end of said tubular casing (7).

2. Goal detection system (1) according to claim 1, comprising a connector intended to be connected to the detection camera (8) having cables capable of being integrated into the net lifting device (11) of a football or handball goal, and a housing (12) comprising a data processing unit (13) and optionally a wireless communication system.

3. Goal detection system (1) according to any one of claims 1 or 2, wherein said system comprises two camera housings (6a and 6b) each having a detection camera (8) which camera housings are mounted behind a goal line at the base of each side post (4a and 4b), in a configuration where the lenses of the cameras point opposite each other parallel to the axis of the goal line YY', and in a direction ZZ' distant from 0 to 22 cm from the axis of the goal line YY'.

4. Goal detection system according to any one of claims 1 to 3, wherein the detection system comprises two electronic boards, an output PCB board (23) connected to the tubular formwork (7), and a connection PCB board (24) intended to be connected to the camera.

5. Net lifting device (11) comprising a goal net (3), and comprising a first and a second ground fixing bars (16 and 17) of the goal net (3) and a detection system according to one of the preceding claims, the camera housing(s) (6, 6a and 6b) being integrated into the ground fixing bar(s) (16 and 17) of the net (3).

6. Net lifting device (11) according to claim 5, wherein the first and second ground fixing bars (16 and 17) of the goal net have waiting tubes mounted in place of said camera housings (6a and 6b).

7. Net lifting device (11) according to any one of claims 5 or 6, comprising two bent tubes (19a and 19b) and a rear tube (18) connected perpendicularly to the first and second fixing bars (16 and 17) on the ground by the two bent tubes (19a and 19b).

8. Thread lifting device (11) according to claim 7, comprising at least one rear fitting (20), and the rear tube (18) being in at least two detachable tube parts connected by at least one rear fitting (20).

9. Goal cage (2) comprising two side posts (4a and 4b), a crossbar (5) fixed to the two posts at each of its ends, a net (3), and a net lifting device (11) according to any one of claims 5 to 8, for tensioning the net (3) integrated into said lifting device behind the goal line.

10. An image processing method implementing the target detection system according to any one of claims 2 to 4 comprising a camera (8), and comprising the steps of: - capture of images taken at goal level by the camera (8); - continuous analysis by the data processing unit (13) to detect the passage of a balloon and - the implementation of an algorithm to determine if the ball has crossed the goal line.

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