Abstract: A differential roller screw comprises an outer nut, and rolling elements comprising a first set of rollers equipped with first grooves, the first set being arranged in a first cylindrical ring around the screw. The screw comprises a second set of rollers equipped with second grooves. The second set is arranged in a second cylindrical ring. The two cylindrical rings are coaxial. An intermediate cylindrical element is arranged between the two sets of rollers, the intermediate element comprising a first internal thread formed with a first pitch and having a first direction and a second external thread formed with a second pitch and having a second direction opposite the first direction.

Abstract: A deployable structure with panels forming an antenna equipped with a solar generator includes: a set of antenna panels each having a substantially rectangular useful surface, the antenna panels abutting each other on first sides parallel to each other, at least one photovoltaic solar panel, each photovoltaic solar panel abutting an antenna panel on a second side of said antenna panel perpendicular to the first sides, first articulation systems, each of said articulation systems enabling an antenna panel to be caused to pivot relative to an adjacent antenna panel about an axis substantially parallel to the first sides of said antenna panels, a second articulation system for each photovoltaic solar panel, each of said articulation systems enabling a photovoltaic solar panel to be caused to pivot relative to the antenna panel that it abuts about an axis substantially parallel to the second side of said antenna panel.

Abstract: The present invention relates to a reusable device for securely holding at least one fragile object against a functional surface solidly fixed to the structure of a satellite or spacecraft during at least one operational phase relating to this satellite, making the objects thus held more accessible and intervention on these objects easier, while at the same time preventing damage to these objects under the effect of sudden accelerations, both during this (these) operational phase(s) and while the hold is being established or while the hold is being released. The device according to the invention is characterized in that it comprises a rigid structure which partially grips this (these) object(s) and which supports at least one fixed jaw and at least one moving jaw substantially facing the fixed jaw(s), the object being immobilized between the fixed jaw and the moving jaw throughout the period of firm holding.

Abstract: An actuation system for at least two mobile elements with dynamically compensated and opposite relative motions, without disturbance of the elements fixed in the same rigid structure as it, and resistant to exterior loadings, in the case of a translational motion of the mobile elements, includes, in a rigid structure, at least one linear actuator linked to a motion transmission device with four rigid arms, articulated at their ends and forming a lozenge, of which each of two first opposite vertices is linked to a corresponding mobile element, and whose other two opposite vertices have a single translational degree of freedom.

Abstract: A protection device for an optical instrument of a satellite including a body on which the optical instrument is mounted, the optical instrument including a central mirror and peripheral mirrors reflecting light towards the central mirror, said protection device having a folded position and a deployed position, includes a plurality of panels rigid in the deployed position, the device forming a cellular structure including a tube for each peripheral mirror, the section of the tubes being a polygon, the tubes being disposed in such a manner as to protect the peripheral mirrors against stray illumination, and said panels being held against the body of the satellite in the folded position.

Abstract: In the field of antenna reflectors with a deformable reflecting surface, an actuation system, with which such a reflector may be equipped wherein the reflector includes a chassis, a flexible membrane fixed to the chassis, comprises: a support fixed to the chassis, a set of deformation devices, each deformation device including a pusher element adapted to be driven in translation relative to the support along an axis, the pusher element including a part adapted to come into contact with the flexible membrane at a point to deform it, an actuation device adapted to drive the pusher element of one of the deformation devices in translation at the same time, and a selector device adapted to move the actuation device toward each of the deformation devices.

Abstract: A deployable structure with panels forming an antenna equipped with a solar generator includes: a set of antenna panels each having a substantially rectangular useful surface, the antenna panels abutting each other on first sides parallel to each other, at least one photovoltaic solar panel, each photovoltaic solar panel abutting an antenna panel on a second side of said antenna panel perpendicular to the first sides, first articulation systems, each of said articulation systems enabling an antenna panel to be caused to pivot relative to an adjacent antenna panel about an axis substantially parallel to the first sides of said antenna panels, a second articulation system for each photovoltaic solar panel, each of said articulation systems enabling a photovoltaic solar panel to be caused to pivot relative to the antenna panel that it abuts about an axis substantially parallel to the second side of said antenna panel.

Abstract: The invention is situated in the field of telecommunication satellites. A deployable structure with which such a satellite may be equipped and a method of deploying the deployable structure is provided. The deployable structure includes: a set of primary panels, a set of secondary panels, primary articulation systems, each primary articulation system enabling a primary panel to be caused to pivot relative to another primary panel about a primary axis, the primary axes being substantially parallel to the primary panels, and secondary articulation systems, each secondary articulation system being associated with a secondary panel and enabling said panel to be caused to pivot relative to another panel about a secondary axis parallel to said panels, the deployable structure being configured in such a manner that, in a deployed configuration, the front surfaces of the panels form a substantially continuous overall surface.

Abstract: A self-driven articulation designed for automatically deploying the elements that it connects comprises two articulation fittings made to rotate under the action of at least one passive drive element. The articulation comprises means for regulating the speed at which it deploys.

Abstract: A device for protecting an optical instrument of a satellite comprises a body on which the optical instrument is mounted, said protection device having a folded-down position and a deployed position, and further comprising a plurality of rigid panels in the deployed position, the device forming a tube, the section of which is a polygon, arranged so as to protect the optical instrument, the longitudinal axis of the tube being substantially parallel with the focal axis of the optical instrument, the faces of the tube of polygonal section being formed by panels, in the folded-down position, said panels being held against the body of the satellite.

Abstract: A deployment system for spatial appendages, such as, for example, solar generators, comprises at least one two-phase deployment articulation line, furnished with two rotation spindles. The deployment system comprises a synchronization mechanism for the two rotation spindles so that when the driving spindle rotates during a first deployment phase, the driven spindle does not rotate, and then, when the driving spindle rotates during the second deployment phase, the driven spindle rotates in a manner synchronized with the driving spindle.

Abstract: A differential roller screw comprises an outer nut, and rolling elements comprising a first set of rollers equipped with first grooves, the first set being arranged in a first cylindrical ring around the screw. The screw comprises a second set of rollers equipped with second grooves. The second set is arranged in a second cylindrical ring. The two cylindrical rings are coaxial. An intermediate cylindrical element is arranged between the two sets of rollers, the intermediate element comprising a first internal thread formed with a first pitch and having a first direction and a second external thread formed with a second pitch and having a second direction opposite the first direction.

Abstract: A solar generator deployment device includes at least one primary tape-spring supporting a flexible membrane with a set of flexible photovoltaic cells on one face, at least one secondary tape-spring, and a reinforcing structure attached to the primary tape-spring and secondary tape-spring, said device having a wound state in which the primary tape-spring supporting the flexible membrane and secondary tape-spring and reinforcing structure are co-wound around a mandrel; and an unwound state in which said primary tape-spring and secondary tape-spring are unwound. The device comprises, at the level of said mandrel, means for offsetting, in the unwound state, the root of said secondary tape-spring so that the reinforcing structure is deployed within a volume situated on the side opposite the face of the flexible membrane comprising flexible photovoltaic cells and supports said flexible membrane, the device then being in the deployed state.

Abstract: A solar generator deployment device includes an assembly comprising a plurality of tape-springs supporting a windable membrane on a face of which is arranged a plurality of elements capable of converting the solar energy into electrical energy. The tape-springs and membrane are co-wound around a unique radius of curvature equal to the natural radius of curvature of folding of the tape-spring in the wound state. The tape-springs are substantially parallel and interlinked by transversal braces ensuring the rigidity of the bearing structure.

Abstract: A motorisation device comprises two substantially parallel winding cylinders, and at least one longitudinal linking element able to maintain a predetermined distance between the winding cylinders and wound around winding tracks, the linking element consequently having a crossing point located between the winding cylinders. The motorisation device includes two flexible tracks, fixed on each of the winding cylinders and arranged to face and to touch eachother at the contact point, a pre-stressing force being applied to the contact point under the effect of said linking element. The flexible tracks are spiral shaped and arranged such that the contact point between the two spiral-shaped flexible tracks, located between the winding cylinders, is offset relative to the crossing point of the linking element, such that a torque dependent on the distance between the contact point and the crossing point is applied to the contact point, causing reciprocal rotation of the flexible tracks.

Abstract: A frictionless self-driven articulation designed to be mounted between two neighboring elements, including two cylindrical fittings rotationally driven through the action of a leaf spring, the ends of the leaf spring being fixed respectively to each of the fittings. The articulation includes means of retaining the fittings and load transfer means separate from the retention means.

Abstract: An actuation system for at least two mobile elements with dynamically compensated and opposite relative motions, without disturbance of the elements fixed in the same rigid structure as it, and resistant to exterior loadings, in the case of a translational motion of the mobile elements, includes, in a rigid structure, at least one linear actuator linked to a motion transmission device with four rigid arms, articulated at their ends and forming a lozenge, of which each of two first opposite vertices is linked to a corresponding mobile element, and whose other two opposite vertices have a single translational degree of freedom.

Abstract: Actuator for a device for the rotary positioning of a movable element for space equipment comprising a part attached to the fixed portion of said equipment, a bearing, a sleeve designed to actuate the movable portion of said equipment and mounted on an output shaft supported by a first race of said bearing, said actuator comprising a mechanically movable input means and being capable of converting a movement of the input means into a rotary movement of the output shaft about the axis of said bearing, characterized in that said second race of said bearing is connected in rotation to the part of said equipment, in that an adjustable stop so as to angularly limit the relative rotation of the two races of the bearing, and in that the rate of rotation of the output shaft in response to a movement of the input means is different depending on whether or not the sleeve is resting on the adjustable stop.

Abstract: The present invention consists of an active tie-rod device making it possible to hold and smoothly release space appendages. The active tie-rod device includes a fixed base, an active tie-rod screwed into the said fixed base, a retractable release mechanism for the active tie-rod making it possible, in the stowed position, to hold the said active tie-rod in place, and a nut for tensioning the assembly. The active tie-rod includes an internal heater, and consisting at least partially of a material with a high coefficient of thermal expansion, so that, under the action of the internal heater, the active tie-rod can expand, retracting the retractable release mechanism for the active tie-rod, and consequently allowing the smooth release of the said space appendages.

Abstract: A rotary positioning device of a movable element for space equipment comprising a part attached to a fixed portion of the equipment and a handle actuating the movable portion of the equipment, said handle being rigidly connected to a first race of a ball or roller antifriction bearing and said fixed part being connected to the second race of said antifriction bearing, wherein a link between said fixed part and the second race is an elastic link in rotation about the axis of said antifriction bearing and wherein a stop is rigidly attached to one of the races in order to interact with an element rigidly attached to the other race, so that the relative rotation of the two races of said antifriction bearing is limited angularly.