Installation kit for an image acquisition device for road control machines

Abstract

Installation kit for an image acquisition system for a road control machine comprising:- a plurality of optical devices (3000) with different focal lengths, each optical device comprising an optical lens (3002) and a photosensitive sensor (3001);- a fixing plate (1000) adapted to form a mechanical connection between several optical devices of said plurality of optical devices (3000); wherein - the fixing plate (1000) comprises a fixed context camera (1001) and a plurality of selectable fixing positions (1002) for each optical device of the plurality of optical devices (3000);- said selectable fixing positions (1002) are arranged so as to form a plurality of pre-established alignments between the fixed context camera (1001) and one or more optical devices selected from among the plurality of optical devices (3000);- said pre-established alignments and said selectable positions (1002) are configured according to a correspondence chart; - said correspondence chart provides a plurality of pre-established alignments according to the number and width of the road lanes to be monitored by the automaton, the position and distance to the infraction line of said acquisition system, and the number and focal length of the optical lenses necessary for covering said road lanes.;

Description

Title of the invention: Installation kit for an image acquisition device for road control machines Technical field

[0001] The present invention relates to an installation kit for an image acquisition device for a road control machine. It also relates to a method for installing an image acquisition device for a road control machine using such a kit. Technical background

[0002] It is common practice to control or monitor road traffic using automatons comprising speed cameras - radar or laser devices for measuring the speed and position of vehicles - and optical systems configured for acquiring images of the interior and / or exterior of vehicles. These automatons are programmed to detect and characterize certain road traffic offenses committed by drivers of vehicles through the combined analysis of the signals from the speed cameras and the acquired images. In particular, they make it possible to produce the elements of typing and proof of the offense and to extract from the images the identification information such as the registration numbers of the vehicles for drawing up the report.

[0003] The reliability of these automatons is based in part on the accuracy and robustness of the arrangements and alignments of the speed cameras and optical systems with each other in order to ensure, for each vehicle checked, perfect concordance between the data from the speed cameras and the images acquired by these systems. This concordance is essential to remove any ambiguity as to whether a vehicle identified as having committed an offense by the speed cameras corresponds exactly to the vehicle of which an image is acquired by the optical devices for its identification.

[0004] In addition to this optical coupling between speed cameras and optical devices, the optical systems must also be oriented in specific directions depending on the topographical constraints of the road environment in which the control system is installed and the number and width of the lanes to be controlled. It is common practice to manually adjust the positions and orientations of the optical devices in the factory. These adjustments, which may be, in certain cases, supplemented by adjustments on the installation site, are based on the ability of a human operator to analyze a certain number of images acquired by the optical systems during the passage of vehicles and to establish an optimal configuration for all the optical elements in order to ensure both maximum coverage of the lanes and the best match between speedometer data and acquired images. There are also automatons to facilitate installation and reduce human errors.

[0005] EP 2 690 459 A2, JENOPTIK ROBOT GMBH [DE], 29.01.2014 describes a road control automaton comprising a radar or laser speed camera and two cameras, one of which is a high-resolution camera. The speed camera and the two cameras are arranged so that their respective optical fields overlap. The automaton comprises a data processing unit configured to identify objects in the images acquired by the two cameras and compare their positions with those measured by the speed camera.

[0006] EP 3 012 652 Al, MORPHO [FR], 27.04.2016 describes a road control unit comprising a speed camera and optical devices mechanically assembled together using a plate. The plate comprises an assembly of a main part and two secondary parts, the two secondary parts are each adapted to support an optical device. The three parts comprise removable fixings configured to orient the optical devices in a predetermined constant angular orientation relative to a radioelectric axis of the speed camera. Margins for adjusting the orientation are provided to take into account possible variations in the widths of the traffic lanes of the road, the average speed of vehicles on the road, or the topography of the installation site of the road control unit. The orientation and its adjustment margins are determined by the plate itself for each optical device.This unit simplifies its installation and improves the accuracy of its adjustment to ensure concordance between the vehicle controlled by the speed camera and that appearing on the images acquired by the optical devices.

[0007] WO 2022 / 223921 A1, IDEMIA IDENTITY & SECURITY FRANCE [FR], 27.10.2022 describes an image acquisition device comprising a single-piece stage and three optical devices whose optical axes are coplanar. The optical axes of the three optical devices are oriented so that their field angles partially overlap and the optical vectors supporting their optical axes satisfy particular vector relationships. The stage may further comprise a fourth optical device whose optical axis intersects with the optical axes of two of the other optical devices at a given point in space. This device allows the acquisition of a low-resolution wide-angle image in which a high-resolution low-field image assembly is reported. The device is more economical in that it dispenses with the use of a high-resolution wide-angle optical device. Summary of the invention Technical problem

[0008] A disadvantage of the control unit described in EP 3 012 652 A1, MORPHO [FR], 27.04.2016 is the lack of modularity, customization and adaptability. The fixing plate of the control unit is dedicated to a given range of installation distance values ​​and, according to this range, to optical devices with given focal lengths. Thus, it is necessary for an operator to have available a set of interchangeable plates on each of which is inscribed the range of installation distance values ​​and the dedicated focal lengths.In the event of changes in the topography of the controlled area and / or in the characteristics of the road along which the unit is installed, such as the number and / or width of lanes, a change of orientation, or the construction of peripheral noise-reduction embankments, the operator may be required to completely replace the existing plate with a new one with all its objectives, and to carry out new adjustments. Not only does such a substitution constitute a waste of time but also a material loss if the old plate cannot be reused.

[0009] Another disadvantage of the control unit is that it is necessary to manufacture a plurality of different mounting plates for each interval of installation distance values ​​and each dedicated set of optical lenses. Such a multiplication of the distinctive characteristics between the plates implies the use of production lines specific to each plate, and therefore an additional production cost. In addition, there is a risk that a certain number of plates dedicated to certain intervals of installation distance values ​​and certain optical lenses are produced unnecessarily if they are not used due to lack of opportunities. This results in a material and financial loss. Technical solution

[0010] According to a first aspect of the invention, there is provided an installation kit for an image acquisition system for road control machines comprising: - a plurality of optical devices with different focal lengths, each optical device comprising an optical lens and a photosensitive sensor; - a fixing plate adapted to form a mechanical connection between several optical devices of said plurality of optical devices; in which - the mounting plate comprises a fixed context camera and a plurality of selectable mounting positions for each optical device of the plurality of optical devices; - said selectable fixing positions are arranged so as to form a plurality of pre-established alignments between the fixed context camera and one or more optical devices selected from the plurality of optical devices; - said pre-established alignments and said selectable positions are configured according to a correspondence chart; - said correspondence chart provides a plurality of pre-established alignments according to the number and width of the road lanes to be monitored by the automaton, the position and distance to the infraction line of said acquisition system, and the number and focal distance of the optical lenses necessary to cover said road lanes.

[0011] Advantageous embodiments are described below.

[0012] According to a second aspect of the invention, a method is provided for installing an image acquisition system for road control machines using a kit according to the first aspect of the invention. Brief description of the drawings

[0013] [Fig-1] is a schematic perspective representation of a plate for an installation kit according to the first aspect of the invention.

[0014] [Fig.2] is a schematic representation in front view of the plate of [Fig. 1].

[0015] [Fig.3] is a schematic perspective representation of an optical device.

[0016] [Fig.4] is a schematic representation of a fixing plate on which are fixed two devices according to a first pre-established alignment.

[0017] [Fig.5] is a schematic representation of a fixing plate on which are fixed two devices according to a second pre-established alignment. Detailed description of the embodiments

[0018] In a first aspect of the invention, with reference to [Fig.l] to 3, there is provided an installation kit for an image acquisition system for a road control machine comprising: - a plurality of optical devices 3000 with different focal lengths, each optical device comprising an optical lens 3002 and a photosensitive sensor 3001; - a fixing plate 1000 adapted to form a mechanical connection between several optical devices of said plurality of optical devices 3000; in which - the fixing plate 1000 comprises a fixed context camera 1001 and a plurality of selectable attachment positions 1002 for each optical device of the plurality of optical devices 3000; - said selectable fixing positions 1002 are arranged so as to form a plurality of pre-established alignments between the fixed context camera 1001 and one or more optical devices selected from the plurality of optical devices 3000; - said pre-established alignments and said selectable positions 1002 are configured according to a correspondence chart; - said correspondence chart provides a plurality of pre-established alignments according to the number and width of the road lanes to be monitored by the automaton, the position and distance to the infraction line of said acquisition system, and the number and focal distance of the optical lenses necessary to cover said road lanes.

[0019] In the context of the present invention, with reference to [Fig. 3], the term "optical device" is understood to mean a device 3000 capable of acquiring images, photographs or videos of roadways at given focal distances and magnifications. Such a device generally comprises an optical objective 3002 and a photosensitive sensor 3001. In [Fig. 3], the photosensitive sensor 3001 is supported by an electronic card arranged inside a chassis 3003. The optical device 3000 may further comprise an electronic connector 3004, such as a pin connector, for its power supply and the transmission of the acquired images to a data processing device such as a computer.

[0020] The term "photosensitive sensor" 3001 means a photosensitive electronic component capable of converting electromagnetic radiation, in particular ultraviolet, visible or infrared electromagnetic radiation, into an electrical signal, then processing it to form an image. Such an electronic component is generally devoid of any optical element, such as a lens, capable of forming an optical system whose main function is to modify the trajectory of the electromagnetic radiation before its capture by the active surface of said component. Optionally, in the case of a digital photosensitive sensor, the active surface of the photosensitive sensor may be provided with microlenses whose function is to concentrate the electromagnetic radiation on each pixel of the active surface. These microlenses are part of the active surface of the sensor and are not added elements.

[0021] “Optical objective” 3002 is understood to mean an optical system whose main function is to modify the trajectory of electromagnetic radiation. In particular, “optical objective” is understood to mean an optical device formed from a succession of spherical, aspherical or planar diopters, such as optical lenses, and capable of forming the image of an object located at certain depths of field. A A photographic lens is an example of an optical lens that can be used within the scope of the invention.

[0022] The term “fixing plate” 1000 means any support capable of supporting optical devices 3000 and ensuring a secure mechanical connection between them. This support is generally a flat support provided with at least one main part on which the context camera and the optical device(s) can be fixed. The support is preferably made of metal or metal alloy. It may be made of steel or aluminum alloy.

[0023] According to the invention, the selectable fixing positions are arranged so as to form a plurality of pre-established alignments between the fixed context camera 1001 and one or more optical devices selected from among the plurality of optical devices 3000. In other words, with reference to [Fig.4] & 5, each of the selectable fixing positions 1002, when one or more optical devices 4001, 4002, 5001, 5002 are mounted therein, orients the optical axis (AO1), (AO2) of said optical devices 4001, 4002, 5001, 5002 according to a given pre-established direction relative to the optical axis (AO0) of the context camera 1001. The context camera 1001, more precisely its optical axis (AO0), thus serves as a reference axis for each alignment of the plurality of alignments.

[0024] According to a first example of alignment, with reference to [Fig. 4], the two optical devices 4001, 4002 are fixed on selectable fixing positions 1002 whose pre-established alignments orient their optical axes (AO1), (AO2) in a direction parallel to the optical axis (AO0) of the context camera 1001. According to a second example of alignment, with reference to [Fig. 5], the two optical devices 5001, 5002 are fixed on selectable fixing positions 1002 whose pre-established alignments orient their optical axes (AO1), (AO2) respectively in two different angle directions a, [3 relative to the optical axis (AO0) of the context camera 1001.

[0025] The alignments are generally pre-established from the design and manufacture of the plate and the optical devices. Thus, the alignments can be adapted to the current topographies of the control zones likely to be controlled by the road control machine in which the kit according to the first aspect of the invention is implemented. The alignments are pre-established to be able to cover any type of control zones in curved, straight and / or inclined road sections, such as bends, straights, climbs and descents. The alignments can also be adapted to the topographies of particular control zones, in particular according to the geographical particularities of the places where these zones are located.

[0026] The selectable fixing positions 1002 and the preset alignments they establish are configured according to a correspondence chart that provides a plurality alignments according to the width of the road lanes to be monitored by the automaton, the position and distance to the infraction line of said acquisition device, and the number and focal length of the optical lenses necessary to cover said road lanes. Preferably, the correspondence chart covers from 2 to 8 road lanes. An example of a chart is provided in Table 1.

[0027] [Tab. 1] Tab 1 Number of optical devices 1 1 1 1 2 2 2 Focal length (mm) 16 25 35 50 25 35 50 2 ways Min distance (m) 10 14 20 28 10 12 16 Max distance (m) 20 30 44 60 28 40 56 3 ways Min distance (m) 14 20 28 40 12 16 24 Max distance (m) 20 30 42 60 26 36 46 4 ways Min distance (m) 18 26 30 52 15 19 27 Max distance (m) 20 30 44 60 26 39 56 5 ways Min distance (m) NO NO NO NO 18 24 32 Max distance (m) 26 38 52 6 lanes Min distance (m) NO NO NO NO 20 28 40 Max distance (m) 26 38 52 7 lanes Min distance (m) NO NO NO NO 22 32 44 Max distance (m) 26 38 52 8 lanes Min distance (m) NO NO NO NO 26 36 50 Max distance (m) 26 38 56

[0028] According to a first example, from the chart in Table 1, for a control automaton located between 10 and 20 meters from a control zone comprising two lanes, a single optical device with a focal length of 16 mm can be selected from the plurality of devices of the kit according to the first aspect of the invention. The optical device can then be fixed on the fixing plate on the selectable fixing positions provided for said optical device.

[0029] According to a second example, from the abacus of table 1, for a control automaton located 40 to 52 meters from a control zone comprising six lanes, two optical devices with a focal length of 50 mm can be selected from the plurality of devices of the kit according to the first aspect of the invention. The two optical devices can then be fixed on the fixing plate at the selectable fixing positions provided for said optical devices.

[0030] The abacus is of any suitable form. It can be implemented on a physical medium, such as a manual or paper diagram, which accompanies the kit according to the first aspect of the invention. It can also be implemented on a dematerialized medium such as a tablet on which it is previously loaded or can be downloaded via the reading of a code-forming symbol, such as a 2D barcode ("data matrix"), affixed to the plate. Advantageously, the correspondence abacus can be part of an augmented reality software suite having the function of virtually superimposing an image of the optical devices on the appropriate selectable positions of the plate according to the number and width of the road lanes to be monitored by the automaton, the position and distance to the infraction line of said acquisition device, and the number and focal length of the optical lenses necessary for the coverage of said road lanes.Such a function can advantageously assist an operator in implementing a kit according to the first aspect of the invention.

[0031] The context camera 1001 has the function of providing a wide visualization, or even a panorama, of an area likely to be controlled by a control automaton in which a kit according to the first aspect of the invention is used. Also, according to a preferred embodiment, the context camera 1001 is a wide-angle camera, preferably with high resolution. It may comprise a short focal length lens with a field angle of at least 50°, preferably at least 70°, or even at least 90°. The context camera is preferably a high-resolution camera allowing in particular the acquisition of images with a definition of at least 720p, or even 1080p.

[0032] The context camera 1001 is mechanically secured to the fixing plate 1001. It can be fixed there using any suitable fixing means, preferably removable, such as a screw / nut assembly. With reference to [Fig.l] to 5, it can be arranged on any suitable part of the fixing plate 1001, in particular on a part where the optical devices 4001, 4002, 5001, 5002, capable of being fixed on said plate, do not obstruct its field of vision. It can be fixed on the same face 1000a as that on which one or more optical devices 4001, 4002, 5001, 5002 are capable of being fixed, or on an opposite face.

[0033] According to a preferred embodiment, with reference to [Fig.l], the optical axis (AO0) of the context camera 1001 coincides with an axis of symmetry (A) of the fixing plate 1001. For example, the optical axis (AO0) of the camera 1001 may coincide with the axis of symmetry (A) of the face 1000a of the plate serving as support for the context camera 1001 and the optical devices. This arrangement is advantageous in that it facilitates the definition of the selectable positions forming pre-established alignments during the design and manufacture of the fixing plate, and allows the kit to be used on both sides of a road.

[0034] The kit according to the first aspect of the invention may comprise any type of optical device 3000 suitable for controlling roadways, in particular for producing elements for typing and providing evidence of traffic violations and extracting from the acquired images identification information such as vehicle registration numbers. According to certain embodiments, the plurality of optical devices 3000 comprises short focal length optical lenses 3002 whose focal length varies between 10mm and 100mm, preferably between 15mm and 50mm.

[0035] The size of the fixing plate 1000 and the number of its selectable positions depend on the number of optical devices 3000 that it is capable of supporting and for which there is no limit. Nevertheless, according to preferred embodiments, the fixing plate is arranged to receive at least one optical device, at least two optical devices, or even at least three optical devices.

[0036] The number of optical devices that the kit according to the first aspect of the invention can comprise depends on the number of different configurations that the correspondence chart is capable of covering with regard to the characteristics of the areas that can be controlled. The kit can comprise four pairs of optical devices, each pair corresponding to a different focal length.

[0037] The selectable fixing positions 1002 are of any type suitable for fixing the optical devices. With reference to [Fig.l] & 2, they may for example be in the form of orifices in which the optical devices can be fixed, for example by clipping or by a screw / nut assembly. In a preferred embodiment, with reference to [Fig.4] & 5, the fixing plate 1000 is provided with removable fasteners 4003, 5003 suitable for fixing the devices of the plurality of optical devices 4001, 4002, 5001, 5002. The removable fasteners may for example be screw / nut assemblies intended to be introduced into the orifices 1002a, 1002b corresponding to the selectable positions 1002.

[0038] With reference to [Fig. 3], 4 & 5, the optical devices 3000 may advantageously comprise a fixing frame 3003, 4001a, 5001a adapted to facilitate its fixing on the fixing plate 1000. For example, the frame 3003, 4001a, 4002a, 5001a, 5002a may be provided with two fixing lugs 3005, 4001b, 4002b, 5001b, 5002b located on either side of the devices 3000, 4001, 4002, 5001, 5003. When the selectable fixing positions 1002 are in the form of an orifice 1002a, 1002b, each fixing lug 3005, 4001b, 4002b, 5001b, 5002b may include a hole arranged to correspond to a hole corresponding to a selectable attachment position. Each attachment tab 3005, 4001b, 4002b, 5001b, 5002b may then be attached to the attachment plate 1000 at using a removable fastening means such as a screw / nut assembly 3006, 4003, 5003.

[0039] According to advantageous embodiments, the fixing frame 3003, 4001a, 4002a, 5001a, 5002a of each optical device 3000, 4001, 4002, 5001, 5002 is arranged so that it can only be fixed in a limited number of selectable fixing positions, for example one, two or three positions. Such an arrangement provides a foolproof function. The risk of error likely to be made by an operator when installing optical devices on the plate in accordance with the invention can thus be significantly reduced. For example, after selecting one or two devices using the chart, the operator cannot make the mistake of inadvertently installing the optical devices in the wrong fixing positions.

[0040] According to one embodiment, the selectable fixing positions 1002 are arranged so that the pre-established alignments have a margin of adjustment, preferably a margin of adjustment of less than 5°, or even 2°, or even 1° on either side of a nominal orientation of said pre-established alignments. As an exemplary embodiment, with reference to [Fig.l] & 2, certain orifices 1002a corresponding to each selectable fixing position 1002 may be oblong in shape and provide a margin of adjustment by cooperation with a circular orifice 1002b having a pivot function.When an optical device 3000 is fixed to the fixing plate using, for example, two screw / nut assemblies corresponding to two holes of a selectable fixing position, the screw / nut assembly mounted in the circular hole 1002b remains fixed to form a pivot while the screw / nut assembly mounted in the oblong hole 1002a can move along said hole to allow the movement of the optical device in a plane substantially parallel to that of the plate. The center of the hole corresponds to the nominal orientation of the pre-established alignment and its length constitutes an adjustment margin of less than 5°, or even 2°, or even 1° on either side of this nominal orientation. Once the orientation is chosen, the screw / nut assembly mounted in the oblong hole 1002a is tightened to lock the optical device 3000 in this orientation.

[0041] According to a second aspect of the invention, there is provided a method of installing an image acquisition device for road control machines. The method makes it possible to use and implement an installation kit in accordance with the first aspect of the invention. The method comprises the following steps: - provide an installation kit for an image acquisition device according to any one of the embodiments of the first aspect of the invention; - assemble the fixing plate 1000 in the space of the machine provided for this purpose; - measuring the position and distance from the fixing plate 1000 to the violation line using the context camera 1001; - select one or more optical devices of the same or different focal lengths from among the plurality of devices 3000 of the kit according to the correspondence chart of the kit as a function of the number and width of the road lanes to be monitored by the automaton, the position and the distance to the infraction line of said acquisition device; - arrange the selected optical objective(s) on the selectable positions 1002 of the fixing plate 1000 according to the correspondence chart. References Patent literature

[0042] EP 2 690 459 A2, JENOPTIK ROBOT GMBH [DE], 01.29.2014.

[0043] EP 3 012 652 Al, MORPHO [FR], 04.27.2016.

[0044] WO 2022 / 223921 A1, IDEMIA IDENTITY & SECURITY FRANCE [FR], 27.10.2022.

Claims

Claims

1. Installation kit for an image acquisition system for a road control machine comprising: - a plurality of optical devices (3000) with different focal lengths, each optical device comprising an optical lens (3002) and a photosensitive sensor (3001); - a fixing plate (1000) adapted to form a mechanical connection between several optical devices of said plurality of optical devices (3000); wherein - the fixing plate (1000) comprises a fixed context camera (1001) and a plurality of selectable fixing positions (1002) for each optical device of the plurality of optical devices (3000); - said selectable fixing positions (1002) are arranged so as to form a plurality of pre-established alignments between the fixed context camera (1001) and one or more optical devices selected from among the plurality of optical devices (3000);- said pre-established alignments and said selectable positions (1002) are configured according to a correspondence chart; - said correspondence chart provides a plurality of pre-established alignments according to the number and width of the road lanes to be monitored by the automaton, the position and distance to the infraction line of said acquisition system, and the number and focal length of the optical lenses necessary for covering said road lanes.;

2. Kit according to claim 1, such that the context camera (1001) is a wide-angle camera, preferably with high resolution.

3. Kit according to any one of claims 1 to 2, such that the optical axis (AO0) of the context camera (1001) coincides with an axis of symmetry (A) of the fixing plate 1001.

4. Kit according to any one of claims 1 to 3, such that the plurality of optical devices (3000) comprises optical lenses whose focal length varies between 10mm and 100mm, preferably between 15mm and 50mm.

5. Kit according to any one of claims 1 to 4, such that the fixing plate (1000) is provided with removable fixings (4003, 5003) adapted to fixing the plurality of optical devices (4001, 4002, 5001, 5002).

6. Kit according to any one of claims 1 to 5, such that the correspondence chart covers from 2 to 8 road lanes.

7. Kit according to any one of claims 1 to 6, such that the fixing plate (1000) is arranged to receive at least one optical device, preferably at least two optical devices, or even at least three optical devices.

8. Kit according to any one of claims 1 to 7, such that the selectable fixing positions (1002) are arranged so that the pre-established alignments have a margin of adjustment, preferably a margin of adjustment of less than 5°, or even 2°, or even 1° on either side of the nominal orientation of said pre-established alignments.

9. Method for installing an image acquisition device for road control machines, said method comprising the following steps: - providing a kit for installing an image acquisition device according to any one of claims 1 to 8; - assembling the plate in the space of the machine provided for this purpose; - measuring the position and the distance of the plate from the infraction line using a context camera; - selecting one or more optical devices of the same or different focal lengths from among the plurality of devices of the kit according to the correspondence chart of the kit as a function of the number and width of the road lanes to be monitored by the machine, the position and the distance from the infraction line of said acquisition device; - arranging the selected optical objective(s) on the selectable positions of the kit according to the correspondence chart of the kit.

10. Use of an installation kit for an image acquisition device according to any one of claims 1 to 8 in a road control machine.

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