Abstract:
The invention concerns a device (D) for managing and starting at least one photographing means ( 100 ), characterized in that it consists of a housing ( 200 ) which, forming a protective chamber around at least one photographing means ( 100 ), is mounted mobile in rotation along a first axis (X) relative to at least one arm ( 310   a ) integral with a plate ( 300 ) which itself is mounted mobile in rotation along a second axis (Y) perpendicular to the first relative to a fixed base ( 400 ), the two rotational movements being performed over three-hundred-and sixty degrees without stop, the arrangement and the dimensions of the photographing means ( 100 ) relative to the arrangement and the dimensions of the plate ( 300 ) and of the base ( 400 ), defining a field of vision of at least two-hundred-and-seventy degrees. The invention also concerns methods for operating such a device. The invention is applicable to detection, control, process monitoring, automated surveillance and/or photograph recording and the like.

Description:
TECHNICAL FIELD OF THE INVENTION 
       [0001]    This invention relates to the field of photographing using or not using a video technique, and in particular to adaptations making it possible to provide the operation of a mobile camera under the best conditions. 
       DESCRIPTION OF THE PRIOR ART 
       [0002]    The prior art discloses a number of solutions for moving a camera, in particular a surveillance camera. These solutions can be classified into two categories: turrets and domes. 
         [0003]    The applicant has noted that the existing solutions have a number of problems, including the following: 
         [0004]    cameras placed inside a protection dome have a reduced zooming capacity due to the presence of said dome. Indeed, beyond a certain focal distance, the objective of the camera will focus from the spherical cap of the concave surface of the dome; 
         [0005]    the cameras used on turrets are either stationary or move very slowly; 
         [0006]    the cameras used in domes cannot provide a view beyond the horizontal plane above or below which they are arranged; 
         [0007]    the effective use of the domes and cameras in general requires regular cleaning of their lens shields (planar surface) for turrets or their spherical cap for domes; 
         [0008]    cameras in domes or installed on turrets require a specialised installer for their installation. 
         [0009]    Thus, for example, the French document 2 665 317 describes a video surveillance camera with an integrated support without a dome, which comprises a photographing device placed in a housing comprising a hollow cover constituted by a base and at least one gimbal arm on which a hollow shell, preferably spherical, rests. The photographing device is placed in the shell, with the connection wires passing from the shell to the inside of the cover through at least one hinge ensuring the mobility of the shell about an axis passing through its centre and perpendicular to the gimbal arm, and the cover itself being mobile about an axis perpendicular to the aforementioned axis and parallel to the gimbal arm. 
         [0010]    This device has the disadvantage of not providing a solution to the management of data concerning the real positioning of the camera on its rotation axes. In addition, the use of hinges as wire passage means has the disadvantage of limiting the possibilities for rotation of the photographing modules to the twisting capacities of said wires. In addition, the photographing housing does not have means for protecting the objective of the camera that it contains. This document remains very vague with regard to the zooming capabilities of the camera. But the diameter of the field of view provided by such a device remains limited to said zooming capabilities. 
         [0011]    The French document 2789253 describes a dome device for a video surveillance camera that is remarkable in that it comprises a protective cap called an ogive, which is not integrated with the shaft, but pivots with the camera, of which the view is provided through an optical window with a flat profile providing a view above the horizontal. The sealing of the lower rotary portion is provided with a lip seal or by a plate with a folded edge that dips into a groove filled with liquid. 
         [0012]    While proposing a viewing window with a planar profile, allowing a view beyond the horizontal and preventing focusing on a spherical surface, this device requires a movement of the protective dome at the same time as the camera for its rotation according to a vertical axis. In addition, the spherical surface is located at the end of the ogive. 
         [0013]    This document remains vague on the zooming capabilities of the camera as well as on the means for controlling its movements. 
         [0014]    Another disadvantage noted in the devices of the prior art concerns the limitation of the number and type of photographing means implemented. Indeed, most devices provide the control and the movement of single photographing means of the conventional video type. 
       DESCRIPTION OF THE INVENTION 
       [0015]    On the basis of this prior art, the applicant has conducted research in order to design a device implementing photographing means or a camera, in particular for video surveillance purposes, overcoming the disadvantages of the prior art. 
         [0016]    The applicant focused on trying to achieve the various advantages seen separately in the devices of the prior art. 
         [0017]    This research led to the design of a device providing the control and movement of at least one photographing means, remarkable in that it is constituted by a housing that, forming a protective chamber around at least one photographing means, is mounted mobile in rotation along a first axis with respect to at least one arm integrated with a plate that is itself mounted mobile in rotation along a second axis perpendicular to the first, with respect to a stationary base, wherein the two rotation movements occur over three hundred and sixty degrees without stopping, with the arrangement and size of the photographing means with respect to the arrangement and the size of the plate and the base defining a field of visibility of at least two hundred and seventy degrees. 
         [0018]    This protective housing is therefore capable of rotating fully according to both a horizontal axis and a vertical axis. The camera has full rotational mobility according to two axes. Its visual field is limited only by the presence of the plate, of which the volume does not prevent the objective of the camera from going beyond the horizontal. Indeed, said plate is advantageously preformed so as not to form an obstacle when the objective of the camera exceeds the horizontal plane. The mobility enables the problems of speed of movement and difficulty of installation to be solved. It is thus no longer necessary to study the camera positioning very precisely in particular according to all of the ground slopes. The device can therefore be arranged right side up or upside down. This device also has no dome and is therefore not equipped with a dome support, which limits the field of view of the device according to an angle of 180° above or below the dome support according to its arrangement. 
         [0019]    To make it possible to propose additional functionalities, the protective housing of the device of the invention can receive a plurality of photographing means of the same technology. This feature makes it possible to envisage instantaneous perimetric photographing without requiring a rotational movement. Similarly, according to another feature, the protective housing can receive a plurality of photographing means of different technologies, such as, for example, infrared or ultraviolet viewing means providing, for a single device, a plurality of viewing solutions. 
         [0020]    Also for the sake of proposing additional functionalities, the applicant has considered certain applications in which the photographing means are associated in the protective housing with at least one sensor thus proposing the recording of non-visual parameters. The applications of such a device go beyond simple surveillance, and include, in particular: detection, monitoring, surveillance of processes, automation of surveillance, photographic recording, etc. 
         [0021]    According to another feature of the invention, the device and the size of the photographing means with respect to the arrangement and size of the plate and base define a field of visibility that is at least two hundred and seventy degrees. 
         [0022]    According to a particularly advantageous feature of the invention, the rotation movements are provided for each axis by a stepper motor and monitored for each axis by an encoder. Thus, the device works in a closed loop, i.e. it has functional elements necessary for recognising the various angular positions taken by the rotating sub-assemblies. In addition, such a position monitoring is entirely suitable for a much more precise control of the movements proposed by the device of the invention, which precision is on the order of one-tenth of a degree. 
         [0023]    According to another particularly advantageous feature of the invention, said protective housing includes a window in front of which the objective of the photographing means is installed, which window is closed by a plate of transparent material. The use of a planar element to protect the objective of the photographing means avoids the disadvantages of the prior art, namely focusing on the protective spherical portions. 
         [0024]    This feature makes it possible to envisage photographing means with zooming capabilities that are largely superior to what is normally provided for dome-type devices. Thus the zooming capabilities are limited only by the current technological limitations of on-board photographing devices. In addition, the device of the invention has been designed to receive the most recent photographing means, of which the zooming and precision capabilities are capable of increasing. Thus, according to another particularly advantageous feature, the zooming capability of the photographing means is at least, if not much greater than, twenty-five. 
         [0025]    According to an alternative, said protective housing can receive a plurality of photographing means and is equipped with a plurality of windows in front of which the objective of the photographing means is installed, windows closed by a plate of material suitable for the type of photographing means. Indeed, according to the type of photographing means (conventional visual spectrum, infrared, ultraviolet, etc.), the protective window may not be protected by the same material. 
         [0026]    Another particularly advantageous feature of the invention relates to its cleaning means. Indeed, the device of the invention is remarkable in that said plate includes, at the level of the base of the arm, at least one cleaning means. Thus, a method for operating the device consists of causing the protective housing to rotate so as to bring the viewing window to the level of the cleaning means in order to carry out the cleaning of the latter. The area toward which the photographing means are blind is therefore advantageously used to receive cleaning means. 
         [0027]    According to another particularly advantageous feature of the invention, said plate is equipped at the base of the arm with projecting elements forming, with the external surface of the rotating housing, a protective chamber. Another method for operating the device consists of causing a rotation of the housing so as to bring the viewing window into said chamber so as to protect it. 
         [0028]    Another operating method consists of integrating a legal locking and unlocking function for image hiding, which can be processed either locally (recorder on-board the device), or by a processing device at the request of the courts. 
         [0029]    While the basic concepts of the invention have been disclosed in their most general form, other details and feature will become clearer on reading the following description, and in view of the appended drawings, given by way of a non-limiting example, an embodiment of a device and methods consistent with the invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0030]      FIG. 1  is a diagrammatic drawing of an external frontal view of an embodiment of the device of the invention. 
           [0031]      FIG. 2  is a diagrammatic drawing of an external side view of the device shown in  FIG. 1 . 
           [0032]      FIG. 3  is a diagrammatic drawing of a frontal cross-section view according to the cutting plane A-A shown in  FIG. 2 . 
           [0033]      FIG. 4  is a diagrammatic drawing of a side cross-section view according to the cutting plane B-B shown in  FIG. 1 . 
           [0034]      FIG. 5  is a diagrammatic drawing according to the view shown in  FIG. 4  with a different protective housing position. 
       
    
    
     DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0035]    As shown in the drawings of  FIGS. 1 ,  2 ,  3 ,  4  and  5 , the device of the invention referenced D, which provides the control of the operation and movement of photographing means  100 , is constituted by a protective housing  200  for said photographing means  100 , which is mounted mobile in rotation along a first axis X with respect to at least one arm  310   a  integrated with a plate  300 , which is mounted mobile in rotation along a second axis Y perpendicular to the first with respect to a stationary plate  400 . As shown, the rotation on these two X- and Y-axes can be performed over 360 degrees without stopping. 
         [0036]    According to the invention, and according to the embodiment shown, said plate  300  includes two arms  310   a  and  310   b  between which said protective housing  200  rotates. According to the technological choice shown, only one arm  310   a  alone provides the guidance and rotational movement of the protective housing according to the X-axis. 
         [0037]    As shown, said protective housing  200  includes a window  210  in front of which the objective  110  of the photographing means  100  is installed. This window  210  is closed by a plate  211  of transparent material that in this case adopts a disk shape. The protective housing is therefore equipped with a window closed by a pane with a planar surface. 
         [0038]    The protective housing  200  forms, according to the preferred embodiment shown, a cylindrical casing closed around the photographing means  100  and of which one angular portion comprises a window  210  for receiving the protective disk  211 . The internal volume of the protective housing  200  is arranged to receive photographing means  100  of any shape. To this end, it is equipped with means  220  for holding said photographing means in position. 
         [0039]    In addition, the fact that the protective surface is planar makes it possible to receive any photographing device comprising almost unlimited zooming capabilities. 
         [0040]    Its visual field is limited only by the presence of the base  400  or the base of the plate  300  of which the volume does not prevent the objective of the camera from going beyond the horizontal. 
         [0041]    According to a particularly advantageous feature of the invention, the arrangement and size of the photographing means  100  with respect to the arrangement and size of the plate  300  and the base  400  (which does not support a dome), which arrangement is defined in particular by the length of the arm at the end of which said photographing means  100  contained in the protective housing  200  are guided in rotation, defining a field of visibility of at least two hundred and seventy degrees. The field of view provided by the device D of the invention therefore defines a partial field of view cut off by a cone of “blindness” corresponding to the presence of the plate  300  and the base  400 , which cone has a maximum angle of ninety degrees. Given that, according to the invention, the photographing means  100  are not limited in their zooming capabilities (except by technical considerations), the diameter of said field of view is capable of varying and in particular of increasing. 
         [0042]    In addition, as shown and according to the invention, said base is preformed so as not to constitute an obstacle when the camera exceeds the horizontal plane. To do this, its volume was reduced. To this end, the plate  300  supporting the arms  310   a  and  310   b  is preformed with bevelled edges so as to minimise the visual obstacle that it may constitute and thus open the field of vision toward the base. Thus, according to the embodiment shown, the angle of the cone of “blindness” is significantly less than ninety degrees, thus increasing the viewing capabilities of the device D. 
         [0043]    The power of the zoom and the resolution capacities of the photographing means  100  are suitable for the precision of the movements that the device D of the invention provides. 
         [0044]    To this end, the device D implements features for driving, drive monitoring and specific controls. 
         [0045]    Thus, the rotation movements are ensured for each axis by a stepper motor. The rotation movement according to the X-axis is implemented by the motor  320  that is housed in the arm  310   a.  The rotation movement according to axis Y is implemented by the motor  330  that is housed in the plate  300 . These stepper motors reach a movement precision on the order of one-tenth of a degree. Similarly, the full speed possible owing to the absence of a stop can reach up to one rotation per second on both axes. 
         [0046]    To provide data on the real angular position of the plate according to the Y-axis or of the protective housing according to the X-axis, the rotation movements are monitored for each axis by an encoder. To do this, each motor  320  and  330  moves a pin, respectively  321  and  331 , which, by means of a flexible link, provides the rotation of the axis of an encoder, respectively  322  and  332 . The encoder makes it possible to return, to the control sub-assembly managing the movements of the device D, the exact angular position taken by the subassemblies at which their axes are kinematically linked. The encoder therefore makes it possible to provide data on the angular position, even if the movement is not generated by the control of the motors (accidental movement, shock, voluntary or involuntary stress on the two axes, etc.). 
         [0047]    The presence of encoders makes it possible to use the precision of the positioning of the motors (to the tenth of a degree), which is not possible with the devices of the prior art. 
         [0048]    The controls, the supply and the input and output data are transmitted at the level of hinges by means of rotating joints or collectors  323  and  333 . The use of these collectors eliminates the need for wires, which are capable of disrupting the rotation movements over  3600  without stopping, on the two X- and Y-axes of the different sub-assemblies. 
         [0049]    All of these features contribute to an optimal use of the velocity capacities in the repositioning of the photographing means  100 . The absence of any limitations on the course and the direction of rotation enables the device to choose the shortest angular course for urgent photographing. The data relayed by the encoders makes it possible to perform a possible image inversion. 
         [0050]    All of these features also contribute to an optimal use of the zooming capabilities, which are no longer limited by the choice of means for protecting the photographing means. 
         [0051]    Nevertheless, the applicant has imagined using the capacities of precision and variation in the focal distance of the photographing means that can effectively be used by the device of the invention, so as to ensure the photographing of elements present in the field of view of the photographing means without moving the latter, which contributes to the efficiency and therefore to an increased lifetime of the sub-assemblies involved in the movements. 
         [0052]    The correspondence between the precision of movement and the precision of the image with the photographing means, of which the resolution is moving toward ten million pixels, makes it possible to envisage the following applications and methods of operation, by means of the electronic sub-assemblies contained in the device: 
         [0053]    detection of activity, inactivity of movement, 
         [0054]    monitoring of a detected and/or pre-defined target, 
         [0055]    processing of the image for an area of interest (digital zoom on a portion of the image without motor movement), with a resolution of around five hundred thousand pixels transmitted, 
         [0056]    integrating a legal locking and unlocking function for image hiding, which can be processed either locally (recorder on-board the device), or by a processing device on request by the courts, 
         [0057]    providing on-board day/night functionalities with slow integration of photons associated with a slow movement of the photographing device (for example a rotation lasting several hours). 
         [0058]    The arm  310   b  forms a free volume capable of containing the aforementioned electronic sub-assemblies. 
         [0059]    The protective window enclosing the protective housing of the device of the invention requires regular cleaning, as in the devices of the prior art. The applicant&#39;s research has resulted in the design of a particularly suitable automatic cleaning device. 
         [0060]    According to the invention, said plate  300  includes, at the level of the base of the arm  310   a,  at least one cleaning means  500 . According to the embodiment shown, these cleaning means  500  are located between the two arms  310   a  and  310   b.  Thus, the cleaning can be performed when the protective housing  200  performs a rotation so as to direct the window  210  toward the cleaning means, i.e. in this case when the window  320  passes between the base of the two arms  310   a  and  310   b.    
         [0061]    The cleaning means  500  can be constituted by a projection nozzle for cleaning fluid (such as a liquid or pulsed air), which may or may not be associated with rubbing means as shown in  FIG. 4 . 
         [0062]    These rubbing means are constituted by a brush  510  and by a rubbing lip or a rubber strip such as a windshield-wiper lip. As shown, a rotation of the protective housing  200  according to its X-axis enables the window  210  to be brushed and/or wiped or vice-versa according to the direction of rotation, and, when the rotation is complete, it stops between the brush  510  and the wiper  520  in the position shown in  FIG. 5 . The device D of the invention therefore has particularly effective cleaning means not requiring external intervention. 
         [0063]    According to another particularly advantageous feature of the invention, the base of the arm is used in another manner. Indeed, as shown, said plate  300  is equipped at the base of the arm, with projecting elements coming into contact with said rotating housing  200  and forming with the external surface of the latter an enclosed volume. According to the embodiment shown, these projecting elements are constituted by said brush  510  and said wiper  520 , which, when the window  210  is directed toward the base of the arms  310   a  and  310   b,  frame and protect said window  210  in the enclosed volume, in the position shown in  FIG. 5 . 
         [0064]    On this basis, the applicant has imagined a method of operation that is remarkable in that it consists of rotating the housing so as to bring the viewing window  210  and the pane  211  closing it into said enclosed volume so as to protect them. 
         [0065]    This self-protective movement can be caused by any event predetermined by the operator, such as, for example, the detection of weather conditions preventing proper operation of the device. Similarly, the optical detection of an element moving at high speed toward the objective of the photographing means can also cause said movement. 
         [0066]    According to the embodiment shown, the arms and the protective housing are preformed so that the ends of the arms reproduce the diameter of the protective housing  200 . The device D thus adopts, at its mobile end, a compact, aerodynamic configuration not having shoulders, projecting elements or crevices. 
         [0067]    It is understood that the device and its methods of operation, which have been described and shown above, have been done so for the purpose of disclosure rather than as a limitation. Of course, various arrangements, modifications and improvements can be made to the example above, without going beyond the scope of the invention. 
         [0068]    For example, although the embodiment shows a device with a protective housing receiving a single photographing means, the features described above also apply to housings arranged to receive a plurality of photographing means, possibly of different technologies that may or may not be associated with at least one sensor.