OPTRONIC SYSTEM FOR PLATFORM AND ASSOCIATED PLATFORM

Description

[0001] The present invention relates to an optronic system. The present invention also relates to a platform equipped with such an optronic system.

[0002] In the field of vehicle observation and protection, it is known to use a short-range observation device with another long-range observation device.

[0003] For this purpose, the short-range observation device includes hemispherical vision equipment installed on a vehicle.

[0004] Such equipment provides a vehicle operator with information about the environment outside the vehicle. This information includes real-time 360° images with an elevation of between 75° and -15°, each point of which is precisely referenced.

[0005] In some cases, the equipment is also capable of providing moving target detection information (sometimes referred to as DCM), laser warning detection information (sometimes referred to as DAL) and missile launch detection information (sometimes referred to as DDM).

[0006] To best cover the entire vehicle environment without masking areas, several vision devices are usually placed around the perimeter of the vehicle. This means that the images from each device must be merged to provide a single image to the operator.

[0007] However, such fusion is difficult to achieve in real time and involves, by construction, parax problems and problems linked to the presence of blind zones which are particularly troublesome when the equipment also provides information on moving target detection, laser warning detection and missile launch detection.

[0008] Furthermore, during vehicle movement, fusion is even more difficult since it is also necessary to compensate for the distortions introduced by such movement on an image. In particular, when the vehicle turns, the movement causes blurring on the images to be compensated.

[0009] There is therefore a need for an optronic system capable of providing the aforementioned information on the environment of a platform and which is easy to implement.

[0010] For this, the present description describes an optronic system for a platform according to claim 1.

[0011] According to particular embodiments, the optronic system comprises one or more of the following characteristics, taken in isolation or in all technically possible combinations: the sensor is positioned on a mechanical interface, the mechanical interface being fixed to the support. the optronic system is provided with a protective shield independent of the support. the optronic system is provided with a device for cleaning the hemispherical vision device, the cleaning device comprising a projection nozzle, the projection nozzle being positioned on the shield. the computer comprises means for controlling the exposure time, the gain, and the image rate of the detector as a function of the environmental conditions, means for stabilizing the image as a function of the movements of the system or the display means, means for detecting newly unmasked regions of the scene, for detecting and tracking events or movements in the scene, for embedding information from other interfaces in the displayed image.the optical system comprises a plurality of lenses having a field less extensive than a hemispherical field. the sensor comprises a plurality of detectors each provided with an optic, the set of optics forming the optical system.

[0012] This description also relates to a platform comprising an optronic system as described previously.

[0013] According to particular embodiments, the platform comprises one or more of the following characteristics, taken in isolation or in all technically possible combinations: the platform has a wall, the support being positioned on the wall. the platform is a vehicle having a turret, the support being positioned on the turret.

[0014] Other features and advantages of the invention will become apparent upon reading the following description of embodiments of the invention, given by way of example only, and with reference to the drawings which are: figure 1 , a schematic view of a vehicle equipped with an example of an optronic system, and figure 2 , a schematic side view of the optronic system of the figure 1 .

[0015] There figure 1 represents a vehicle 10.

[0016] Vehicle 10 is a land vehicle.

[0017] For example, vehicle 10 is a military type vehicle such as a tank.

[0018] Such a vehicle 10 is adapted to comprise a plurality of weapons and to protect at least one operator installed inside the vehicle 10.

[0019] According to the example described, the vehicle 10 is equipped with a turret 12 on which part of an optronic system 14 is positioned.

[0020] For example, turret 12 is also equipped with a 16-gun cannon.

[0021] The vehicle 10 comprises a wall 18 delimiting an interior space 20 from an exterior space 22.

[0022] More precisely, in the military context, the interior space 20 is the space to be secured since it is the space in which the operator(s) will operate, while the exterior space 22 is the theatre of operations in which security is more difficult to ensure depending on the environment considered.

[0023] The wall 18 is made of a material sufficiently strong to form an armor plating for the vehicle 10, the vehicle 10 having to withstand shots.

[0024] The optronic system 14 is described more precisely with reference to the figure 2 .

[0025] For convenience, directions are defined.

[0026] A direction normal to wall 18 is symbolized by a Y axis on the figure 2 This direction corresponds to the direction of deposit and will be called direction of deposit Y in the rest of the description.

[0027] A first transverse direction located in the plane of the figure 2 , the first transverse direction being perpendicular to the direction of bearing. This direction is symbolized by an X axis on the figure 2 This direction corresponds to the site direction and will be called site direction X in the rest of the description.

[0028] A second transverse direction is also defined, symbolized by a Z axis on the figure 2 The second transverse direction Z is perpendicular to the bearing direction Y and to the site direction X.

[0029] The optronic system 14 comprises an optronic head 24, a support 26 and a hemispherical vision device 28.

[0030] The optronic head 24 is an optronic head 24 for observing a part of the environment of the exterior space 22 of the vehicle 10.

[0031] The optronic head 24 comprises, for example, cameras capable of capturing visible light, in black and white and / or in color, infrared cameras, rangefinders, or even pointers. The videos and data collected by the optronic head 24 are transmitted to the interior of the vehicle 10 via analog and / or digital signals.

[0032] In this sense, the optronic head 24 is an optronic head 24 with indirect vision, that is to say an optronic head 24 providing vision via a screen which assumes the operation of all the elements involved in the visualization of the scene on the screen.

[0033] Support 26 is positioned on turret 12.

[0034] The support 26 is movable around a first axis Y1, the first axis Y1 being parallel to the bearing direction Y.

[0035] The support 26 is intended to keep the optronic head 24 movable relative to a second axis X2. The optronic head 24 is rotatably mounted on the support 26 around the second axis X2.

[0036] According to the illustrated example, the second axis X2 is parallel to the site direction X.

[0037] The support 26 comprises a wall which makes it possible to delimit an interior volume 30.

[0038] The support 26 comprises two lateral arms 32, 34 and a base 36.

[0039] The two lateral arms 32, 34 and the base 36 are arranged to form a substantially U-shaped part.

[0040] In the particular example of the figure 2 , the two side arms 32, 34 are identical.

[0041] Each of the two lateral arms 32, 34 is located on either side of the optronic head 24 to ensure the maintenance of the optronic head 24.

[0042] Each of the lateral arms 32, 34 extends mainly along the bearing direction Y.

[0043] The wall of each side arm 32, 34 is made of an aluminum-based alloy or any other material.

[0044] For each of the lateral arms 32, 34, an interior volume 30 called lateral volume 38 is defined.

[0045] According to the example shown, each lateral arm 32, 34 has a substantially parallelepiped shape.

[0046] The base 36 has two parts: a central part 40 connecting the two lateral arms 32, 34 and an interfacing part 42 with the wall 18.

[0047] The central portion 40 is hollowed out so that a central volume 44 can also be defined for the central portion 40.

[0048] In this case, the internal volume of the support 26 is therefore the sum of the lateral volumes 38 and the central volume 44.

[0049] The interfacing part 42 is a mechanical interface having, depending on the case of the figure 2 , a cylinder shape with a hollowed-out central portion 40, the interfacing portion 42 delimiting an interior volume 46.

[0050] The interfacing part 42 supports an interface 48 delimiting the interior volume 46. The shape of the interface is chosen so as to adapt to the shape of the optronic head 24.

[0051] The volume delimited by the sum of the interior volume 46 of the interface 42 and the central volume 44 of the central part 40 comprises motors, resolvers intended to control the motors, as well as an electrical rotating joint and / or an optical fiber capable of transmitting signals or data between the optronic head 24 and the interior of the vehicle 10.

[0052] The motors are capable of driving a rotational movement of the support 26 relative to the wall 18 around the first axis Y1.

[0053] The interfacing part 42 is, depending on the embodiments, fixed or elevating. In the case of the figure 2 , the interfacing part 42 is fixed.

[0054] The hemispherical vision device 28 comprises a mechanical interface 50, a sensor 52, a computer 54, a display unit 56 and a human-machine interface 58.

[0055] The mechanical interface 50 is fixed on the rotating support 26.

[0056] The mechanical interface 50 is integral with the rotating support 26.

[0057] In the proposed example, the mechanical interface 50 is fixed on each lateral arm 32, 34.

[0058] According to the example of the figure 2 , the mechanical interface 50 comprises five parts: a first end part 60, a first intermediate part 62, a middle part 64, a second intermediate part 66 and a second end part 68.

[0059] The first intermediate portion 62 connects the first end portion 60 to the middle portion 64 while the second intermediate portion 66 connects the second end portion 68 to the middle portion 64.

[0060] Each end portion is connected to a respective side arm 32, 34.

[0061] The sensor 52 is capable of capturing images of a part of the environment of the vehicle 10.

[0062] The sensor 52 is fixed to the middle portion 64 of the mechanical interface 50 by holding bars. The bars are not shown in the figures for the sake of clarity of these figures.

[0063] For example, sensor 52 is secured by three holding bars.

[0064] In the example described, the support bars are equally distributed at 120°.

[0065] The middle part 64 being integral with the support 26, the sensor 52 is integral with the support 26.

[0066] The sensor 52 corresponds to the highest point of the optronic system 14. The distance between the sensor 52 and the wall 18 along the Z axis makes it possible to define the height of the optronic system 14. In the example described, the height of the optronic system 14 is less than 1 meter.

[0067] The sensor 52 comprises a hemispherical field optical system 72 and a detector 74.

[0068] According to a variant, the sensor 52 comprises a plurality of detectors 74 each provided with an optic, all of the optics forming an optical system 72 with a hemispherical field.

[0069] In the illustrated case, the optical system 72 has a field covering an angular domain greater than or equal to a hemisphere whose axis is oriented towards the zenith.

[0070] For this reason, the optical system 72 is referred to as a “hemispherical field” optical system 72. By this expression, it is understood that the field covered by the optical system 72 is greater than or equal to one hemisphere. The term “suprahemispherical field” is sometimes used to designate this notion.

[0071] The 72 optical system has a large aperture.

[0072] The 72 optical system has variable resolution in the field.

[0073] According to a particular embodiment, the optical system 72 has significant distortions in order to offer increased resolutions in certain angular domains, for example in the equatorial plane, to increase the range of the optics.

[0074] For example, the optical system 72 comprises a fisheye lens, shortened to fisheye (from the English fish eye meaning "fish eye"), or hypergon lens having a focal length of 4.5 mm (millimeters) and 12 pixels per degree. The optical system 72 then comprises one or two lenses as described above to cover a field of 360°.

[0075] In another example, the optical system 72 includes a plurality of lenses having a field of view less than a hemispherical field. For illustration, the optical system 72 is a set of three fisheye lenses, each lens having a focal length of 8 mm and 21 pixels per degree over 120°.

[0076] According to yet another example, the optical system 72 is a very high distortion optic making it possible to cover a field of 360°, with a variable radial resolution depending on the elevation angle which can range from 20 to 22 pixels / ° or more in radial resolution.

[0077] Detector 74 is an array of photodetectors used to define pixels.

[0078] The detector 74 is located in the focal plane of the optical system 72.

[0079] For example, detector 74 is a 4T (4 transistors in the pixel) or larger CMOS array, operating at 25Hz, with low noise (less than 2 electrons) and high dynamic range (greater than 80dB).

[0080] Each pixel is double-sampled and the charge-voltage conversion is performed in each pixel, which ensures the 74 detector has a very low noise level and a large instantaneous dynamic range.

[0081] Furthermore, the control of the exposure (or integration) time, from durations less than 10 ps to durations of 40 ms for example, allows the detector 74 to operate day and night. In nighttime conditions, at very low levels, it is possible to increase the exposure time for example to 100 ms and to reduce the image rate for example to 10 Hz in order to improve the signal to noise ratio of the restored image.

[0082] The computer 54 is adapted to process the images that the sensor 52 is capable of capturing in order to obtain information on the environment of the vehicle 10.

[0083] Typically, the computer 54 is capable of processing data having a size of several Gigabits per second.

[0084] Thus, the computer 54 is capable of operating at a rate greater than or equal to 1 Gigabit per second.

[0085] In the example described, among the information that the computer 54 is capable of obtaining, there is moving target detection information, laser alert detection information and missile launch detection information.

[0086] Calculator 54 is in the interior volume.

[0087] More precisely, the calculator 54 is in the interior volume of the base 36, therefore positioned before the rotating joint.

[0088] The display unit 56 is capable of displaying images processed by the computer 54.

[0089] The display unit 56 is positioned in the interior space 20.

[0090] The human-machine interface 58 allows an operator to control the hemispherical vision device 28.

[0091] The human-machine interface 58 is positioned in the interior space 20.

[0092] According to the example of the figure 2, the display unit 56 and the human-machine interface 58 are merged.

[0093] The operation of the optronic system 14 will now be described.

[0094] In operation, the optronic system 14 has several functions: on the one hand, thanks to the optronic head 24, the optronic system 14 makes it possible to observe a part of the scene using different cameras which can produce images in different spectral bands thanks to the different cameras, such as for example in the visible spectrum, and in the infrared (radiation whose wavelength is between 800 nanometers and 14 micrometers). The cameras make it possible in particular to produce images in the following domains: PIR, SWIR, IR2 (wavelength between 3 micrometers and 5 micrometers) and IR3 (wavelength between 7.5 micrometers and 14 micrometers).

[0095] When the operator commands a rotation around the first axis Y1 of the support 26 holding the optronic head 24, the support 26 rotates and the observer can observe another part of the scene.

[0096] On the other hand, thanks to the hemispherical vision device 28, the computer 54 has additional information on the environment of the vehicle 10. In this case, the computer 54 is able to provide real-time 360° images with an elevation of between 75° and -15° (or more in high elevation and less in low elevation) of which each point is precisely referenced. The computer 54 is also able to provide moving target detection information, laser warning detection information and missile launch detection information.

[0097] The specific positioning of the hemispherical vision device 28 provides the possibility for the hemispherical vision device 28 to observe the environment of the vehicle 10 without masking. In particular, the hemispherical vision device 28 is the highest point of the vehicle 10, which limits masking by other elements of the vehicle 10.

[0098] Furthermore, such positioning allows for better coverage of off-axis illumination, resulting in improved laser alert detection.

[0099] The positioning on the rotating support 26 also ensures rotational stabilization of the sensor 52 (mechanical servo-control in bearing). The phenomenon of image scrolling due to the rotational movement of the vehicle 10 or the turret 12 is thus greatly reduced.

[0100] The proposed optronic system 14 comprises a single hemispherical vision device 28, which avoids positioning a plurality of hemispherical vision devices.

[0101] This results in increased space on the vehicle 10 as well as a gain in terms of weight.

[0102] Additionally, it avoids the difficulty of having to fuse images from hemispherical vision devices.

[0103] The optronic system 14 comprises a single computer 54, which simplifies the transfer of information. In particular, all of the information is centralized in a single location. The simplification of the transfer of information implies a reduction in the connections to be made, which also results in a gain in terms of weight for the vehicle 10.

[0104] The optronic system 14 is thus capable of operating with a high refresh rate.

[0105] The computer 54 also has access to additional information which is the positioning of the rotating support 26, which makes it possible to optimize the quality of the information provided by the optronic system 14.

[0106] The positioning of the 54 calculator also makes it possible to significantly reduce the thermal signature of the 14 optronic system.

[0107] The positioning on the rotating support 26 also provides the possibility of rotating the optical system 72 to make visible areas of the environment which would be obscured by the holding bars of the sensor 52.

[0108] The possibility of rotating the sensor 52 in bearing makes it possible to envisage other embodiments using such a possibility.

[0109] For example, a slow rotation in bearing of the rotating support 26 makes it possible to envisage superresolution techniques on one axis for the hemispherical vision device 28.

[0110] This further increases the quality of the information provided by the 54 calculator.

[0111] According to another example, the optronic system 14 is provided with protective shielding independent of the rotating support 26.

[0112] The shielding is a protective shield protecting the optical system 72 while leaving only the optical system 72 unobscured. The shielding protection helps protect against shrapnel created by an explosion or against bullet fire. It should be noted that the shielding also helps reduce the thermal signature of the optronic system 14.

[0113] For this shielding, it is still possible according to a particular embodiment to exploit the rotation of the optics. Thus, the optronic system 14 is provided with a device for cleaning the hemispherical vision system, the cleaning device comprising a projection nozzle, the projection nozzle being positioned on the shielding.

[0114] The projection nozzle is fixed and capable of sending a jet of water for example.

[0115] Alternatively, the projection nozzle is capable of sending a jet of air.

[0116] Cleaning of the optical system 72 is done by rotating the support.

[0117] Other embodiments are also conceivable for the proposed optronic system 14.

[0118] According to one embodiment, the optical system 72 comprises a single fisheye lens. This makes it possible to simplify connections and to use simpler image processing.

[0119] According to another embodiment, the optical system 72 comprises a plurality of dissociated optics.

[0120] Furthermore, the optronic system 14 is capable of operating on a plurality of spectral bands, such as for example in the visible spectrum, and in the infrared (radiation whose wavelength is between 800 nanometers and 14 micrometers). For example, the optronic system 14 operates on the following spectral bands: PIR, SWIR, IR2 (wavelength between 3 micrometers and 5 micrometers) and IR3 (wavelength between 7.5 micrometers and 14 micrometers). For this, the optronic system 14 comprises, for example, a sensor 52 operating on a first spectral band and an optronic head 24 operating on a second spectral band, the second spectral band being distinct from the first spectral band.

[0121] According to yet another embodiment, the optronic system 14 comprises components for providing both passive imaging and active imaging.

[0122] In each of the embodiments presented, the optronic system 14 is capable of providing information on the environment of the vehicle 10, in particular real-time 360° images with an elevation of between 75° and -15° (or more) of which each point is precisely referenced, moving target detection information, laser warning detection information and missile launch detection information. The optronic system 14 is, moreover, easy to implement.

[0123] The proposed optronic system 14 can be used on unarmored vehicles, ships, helicopters, airplanes or buildings. All of the preceding examples are referred to by the generic term "platform".

[0124] Generally, the platform comprises a wall 18 on which the support 26 is positioned. When the platform comprises a part of the wall 18 corresponding to the highest location for the platform, the support 26 is advantageously positioned on said part of the wall 18 to benefit from the clearest possible field of vision. In the example described, the part of the wall corresponds to the turret 12.

[0125] The present invention covers all technically possible combinations of the embodiments which have just been presented previously.

Claims

1. An optronic system (14) for a platform, the optronic system (14) including: - a support (26) that can be rotated about a first axis (Y1), the support (26) defining an inner space (30), the support (26) comprising two lateral arms (32, 34), a base (36) and a rotary joint, - an optronic head (24) for observing part of the surroundings of the platform, the optronic head (24) being mounted such that it rotates about a second axis (X2), the second axis (X2) being perpendicular to the first axis (Y1), - a unique hemispherical viewing device (28) comprising a sensor (52) with an optical system (72) having an at least hemispherical field, the sensor (52) being able to detect images of part of the surroundings of the platform, and a calculator (54) for processing the images that the sensor (52) detects, the calculator (54) being capable of supplying moving target detection information, laser alert detection information and missile launch detection information. the calculator (54) being capable of operating at a pace greater than 1 Gigabit per second and being capable of treating data having a size superior to several Gigabits per second, the calculator (54) being in the inner space (30) and the sensor (52) being secured to the support (26), the calculator being in the inner volume of the base (36) and positioned before the rotary joint, the sensor (52) including a matrix detector located in the focal plane of the optical system (72), means for displaying images processed by the sensor (52), the matrix detector being at video rate and comprising LxC pixels, with L and C > 2000, each pixel being double sampling correlated and suitable for ensuring a charge-voltage conversion, and 2*C parallelized analog-digital conversion elements, each conversion element in turn including a first analog-digital conversion element with an output having a low level and high gain and a second analog-digital conversion element with an output having a high level and low gain, the optical system (72) having a focal distance controlled as a function of the angle of elevation, the focal distance being the longest in the equatorial plane, and has a numerical aperture of between 0.9 and 1.6, the calculator comprising means for correcting nonuniformities of the detector using correction tables adopted as a function of the temperature and the exposure time of the detector, weighted summing means, for several adjacent pixels, means for adapting the dynamics of the captured image to the dynamics of the scene, means for compressing the dynamics of the captured image as a function of the temporal noises of the detector, increasing with the illumination of the scene, means for adapting the dynamics of the captured image to the dynamics of the display and / or to those of the eye.

2. The optronic sensor according to claim 1, wherein the sensor (52) is positioned on a mechanical interface (50), the mechanical interface (50) being fastened on the support (26).

3. The optronic system according to claim 2, wherein the mechanical interface (50) being fastened on each lateral arm (32, 34).

4. The optronic system according to any one of claims 1 to 3, wherein the optronic system (14) is provided with a protective shield independent of the support (26).

5. The optronic system according to claim 4, wherein the optronic system (14) is provided with a device for cleaning the hemispherical viewing device (28), the cleaning device including a spray nozzle, the spray nozzle being positioned on the shield.

6. The optronic system according to any one of claims 1 to 5, wherein the optical system (72) includes a plurality of objectives having a less extensive field than a hemispherical field.

7. The optronic system according to any one of claims 1 to 6, wherein the sensor (52) includes a plurality of detectors (74) each equipped with an optic, the set of optics forming the optical system (72).

8. A platform including an optronic system (14) according to any one of claims 1 to 7.

9. The platform according to claim 8, wherein the optronic system (14) is unique.

10. The platform according to claim 8 or 9, the platform being a vehicle (10) including a turret (12), the support (26) being positioned on the turret (12).