Abstract: The device comprises at least three isolating modules each having two rigid pieces, one of which is fastened to the carrier structure and the other of which is fastened to the support for the vibrating equipment, these pieces being linked by at least one isolating stud made of an elastomer, which attenuates the transmission of low-amplitude vibrations from the equipment to the structure, the deformation of at least one stud in tension-compression and in shear being limited by three flexible stops each mounted on only one of the pieces and the free end of which is facing the other of said pieces and not in contact with it, at rest. Each stop comprises an elastomer element coming into contact with the facing other piece during deformations of sufficient amplitude of the isolating stud, the stiffness of the elastomer of the stop being greater than that of the stud. Application to the isolation of vibrating equipment on a satellite carrier structure.

Abstract: According to the present invention, each navigation satellite (1) verifies in an autonomous manner the essential information that it transmits to the users, by virtue of unidirectional links received from reference beacons (11).

Abstract: The invention relates to a method for producing a non-developable surface printed circuit and to the thus obtained printed circuit. According to said invention, each electrically conductive pattern (7) of a printed circuit (2) comprises a base (7E), which is arranged on the non-developable surface (6) and obtained by projecting an electrically conductive varnish, and a coating (7R), which is arranged on said base (7E) and made of an electrically well conductive material by means of buffer electrolysis.

Abstract: A sampling spectrophotometer comprising an interferometer is used for performing a spectral analysis of light produced by a source. The sampling is adapted for eliminating uncertainty in the frequencies that are associated with spectral components deduced from an interferogram. Preferably, the interferometer is of Michelson type, and is equipped with at least one staircase mirror in one of the two optical paths. Elementary reflecting strips of the staircase mirror can then be offset with respect to one another according to a variable step.

Abstract: The invention concerns a coating produced by conversion treatment of an outer surface of a semiconductor metal support component (12) and comprising an inner layer (11) adhering to the support component (12) and accepting differential expansion constraints relative thereto, and an outer layer (19) having low solar absorptivity characteristic ? and the inner (11) and outer (10) layers having jointly a high hemispheric emissivity characteristic ? such that the ?/? ration is less than about 30%, and preferably less than 20%, the outer (10) and inner (11) layers consisting of different ceramics from one layer to the other and derived from crystalline forms different from the semiconductor metal or alloy of the metal support component (12). The invention is applicable to radiative outer surfaces of space vehicles.

Abstract: The invention concerns a method for producing electrically conductive patterns on a non-developable surface of an insulating substrate, and the resulting device. The invention is characterized in that it consists in: coating the non-developable surface (6) uniformly with a layer of electrically conductive material (9), which is in turn coated with a layer of protective material (10), and then, using a mobile laser head, eliminating by laser ablation the portions of said protective substance layer (10) which do not cover said electrically conductive patterns, then eliminating the portions of said electrically conductive material (9) exposed by the elimination of said portions of said protective material layer (10).

Abstract: The invention concerns a method which consists in coating uniformly the non-developable surface (6) with an electrically conductive material (9), which is in turn coated, by spraying, with a pattern (10) of polymerizable protective material, said pattern being polymerized as it is being formed, and then selectively eliminating, through the openings (10.8) of said pattern (10), the portions of said electrically conductive material (9) which do not over said electrically conductive patterns.

Abstract: An optical system including a telescope and a principal pointing device for selecting a direction of observation is disclosed. The system furthermore includes at least one secondary pointing device arranged ahead of a part of the entrance of the telescope and oriented fixedly with respect to the principal pointing device. A set of photodetectors records a secondary image formed by the telescope from light rays directed by the secondary pointing device toward the entrance of the telescope The secondary image makes it possible to accurately determine the direction of observation.

Abstract: The invention relates to a detection device, comprising a parabolic mirror (1) and several radiation detectors (2-5). The detectors are placed in the focal plane (O, X?-X, Y?-Y) of the mirror with respective spacings in a common fixed direction (Y?-Y). The detection device further comprises a selector system, connected to each of the detectors (2-5), embodied to successively select each of the detectors and to transmit a received signal from the selected detector. The separations of the detectors (d2-d5) are selected such that a gain diagram, for the reception of said device, has a gain minimum, between two successive gain maxima, each corresponding respectively to one of the detectors, of less than 3.0 dB less than said gain maxima. Such a device permits a sweeping of a zone with several adjacent sub-sweeps from a machine overflying said zone.

Abstract: A sequence of successive images of a scene is formed using the instrument mounted on a moving carrier, by forming at least two images representing one and the same portion of the scene (P) at two successive instants, and the change of orientation of the line of sight is determined by a step of matching homologous characteristic points (A1, A2) in at least two images of the same portion of scene so as to obtain several pairs of homologous points in this portion, and of registering the two images, then by a step of calculating the angular variations in attitude between the two instants at which the two successive images are obtained, by modeling on the basis of a match estimation using a geometric model for associating, with any point (A1) of an image, a corresponding position (P) in the scene and by correcting on the basis of the deviation, in each pair, between on the one hand the estimate, in one of the two images, of the point (A2) homologous to a point (A1) in the other image, provided by the model, and on

Abstract: A spectrophotometer incorporating an interferometer and a dispersive system is adapted to have an enlarged inlet field without degrading its spatial resolution (?yi). To this end, spectral data deduced from measurements performed by means of the interferometer are transferred into spectral data deduced from measurements performed by means of the dispersive system. Such spectrophotometer makes it possible to scan an observation field quickly, and is compatible with use on board a satellite.

Abstract: The invention relates to a detection device, comprising a parabolic mirror (1) and several radiation detectors (2-5). The detectors are placed in the focal plane (O, X?-X, Y?-Y) of the mirror with respective spacings in a common fixed direction (Y?-Y). The detection device further comprises a selector system, connected to each of the detectors (2-5), embodied to successively select each of the detectors and to transmit a received signal from the selected detector. The separations of the detectors (d2-d5) are selected such that a gain diagram, for the reception of said device, has a gain minimum, between two successive gain maxima, each corresponding respectively to one of the detectors, of less than 3.0 dB less than said gain maxima. Such a device permits a sweeping of a zone with several adjacent sub-sweeps from a machine overflying said zone.

Abstract: A control moment gyro comprising a wheel support structure which is mounted on a base by a motor, which is used to rotate the support around a first axis and bearing a wheel arrangement for driving the wheel spinner at a high speed around a second axis perpendicuIar to the first. The support structure includes a tubular part which rotates on the base and a flange which is disposed on only one side of the wheel and which is fixed both to the wheel and the tubular part. The diameter of the wheel and the point at which the wheel is fixed to the flange are proportioned such that the wheel penetrates the tubular part.

Abstract: A sampling spectrophotometer comprising an interferometer is used for performing a spectral analysis of light produced by a source. The sampling is adapted for eliminating uncertainty in the frequencies that are associated with spectral components deduced from an interferogram. Preferably, the interferometer is of Michelson type, and is equipped with at least one staircase mirror in one of the two optical paths. Elementary reflecting strips of the staircase mirror can then be offset with respect to one another according to a variable step.

Abstract: In order to control the attitude of a satellite having at least four gyroscopic actuators with respective spinners mounted on gimbals steerable about axes parallel to one or the other of only two different directions that are fixed relative to the satellite, the attitude of the satellite is measured using sensors on board the satellite, the control torque required to perform an attitude-changing maneuver is calculated, local linearization calculation is performed based on pseudo-inversion of the Jacobean matrix of the function associating the orientations of the actuator gimbals with the total angular momentum of the cluster in order to determine a new gimbal orientation, and precession speeds of at least one of the gimbals of the actuators are controlled to deliver the control torque for reaching the desired configuration.

Abstract: The invention concerns an optical instrument, designed to be used on a satellite, for simultaneously or quasi-simultaneously observing in two opposite angularly separated directions. It comprises at least two telescopes (TA, TB) having angularly spaced apart observation directions, each having a real and accessible exit pupil and respective planar or superimposable image fields, with a width at least five times more than that of the pupil in a specific direction. Optical means provided at the exit pupil are arranged so as to form the image fields in a common overlapping focal plane except in lateral zones whereof the width is substantially equal to that of the exit pupil of the telescopes. In the common focal plane, an assembly of several matrix detectors are arranged and oriented on the superimposition zone of the image fields of the telescopes in the wavefront.

Abstract: An optical splitting device is intended to receive at an input two beams of different wavelengths. The device includes a polarizing beam splitter designed to selectively transmit part of the beam having one of the wavelengths towards a first output or a second output depending on the polarization of said beam. The device further includes a polarization variation system placed upstream of the polarizing beam splitter. By combining the polarization variation device with the polarizing beam splitter it is possible to adjust the distribution of the energy of a beam between the two outputs of the device. Such a splitting device is advantageously incorporated into an optical communication terminal.

Abstract: An optical system with variable pointing comprises a telescope and a principal pointing device selecting a direction of observation. The system furthermore comprises at least one secondary pointing device arranged ahead of a part of the entrance of the telescope and oriented fixedly with respect to the principal pointing device. A set of photodetectors records a secondary image formed by at least a part of the telescope from light rays directed by the secondary pointing device toward the entrance of the telescope. The secondary image makes it possible to accurately determine the direction of observation.

Abstract: The invention concerns a space craft, such as a telecommunication geostationary satellite, comprising a body, at least one main telecommunication antenna having a specific orientation relative to the body, at least a omnidirectional antenna having a field of view opposite to that of the main antennae and at least a radiator extensible by tilting about an axis linked to the craft body between a stowing position wherein it is pressed against the body and an extended position. The axis is positioned substantially in the plane of one surface of the body parallel to the orientation of the omnidirectional antenna and to the surfaces or the surface bearing the main antenna. The radiator tilts at an angle close to 180° from a position wherein it is pressed against one surface bearing a solar panel to a position wherein it extends substantially in the plane of the surface which bears it when it is stowed.

Abstract: For providing video-on-demand (VOD) a set comprising a plurality of N video programs at staggered time intervals is repeatedly transmitting from a VOD server to a network for access by a view box of an user; responsive to a request for access to a selected program by the user, there is selection of that in-progress transmission of the selected program for which a lead-in portion is shortest and storage of the program in a buffer associated with the view box as it is transmitted. A previously stored beginning portion of the selected program having a time length sufficient to compensate for that time interval is selected, in a memory associated with the view box, and outputting to the view box for display. The in-progress transmission stored in the buffer is continuously spliced to a conclusion of the beginning portion. All different video programs in a same set are transmitted with mutual time shifts equal to a fraction of the staggered interval.