Abstract:
In order to disassemble and separate two parts, for example, on a spacecraft such as a satellite or a probe, the invention provides a single actuation push-button (10), driven by a unit (36) and disposed in a housing (12) between a wall thereof (18) and a piston (24), and having a heater (38) associated therewith. A positioning system (20, 26, 32), responsive to a displacement of the part (24) caused by the extension of unit (36), prevents the push-button (10) from being mounted once it has been actuated.
Abstract:
System for generating on board of an aircraft a signal of information, warning or alarm in the case of an abnormality during take-off. According to the invention, the system comprises means (4) which calculate the position Dstop on the runway where the aircraft has to stop if the pilot decides to interrupt immediately the take-off procedure, representing the distance for stopping the aircraft during the acceleration phase of the aircraft during take-off; means (5) for comparing Dstop to the length of the runway L available in order to determine if a take-off interruption is still possible.
Abstract:
The correcting torque magnetically applied to a satellite to control at least its roll/yaw attitude is determined by establishing the direction of the rolling/yawing plane, wherein a correcting torque can be generated strictly in this plane, by the interaction of a magnetic moment produced on board in the plane of the pitch axis and of the earth's magnetic field with said magnetic field. A control law is used whose gains vary as a function of the local magnetic field of the earth to take into account the predetermined stresses exerted on the poles of the system.
Abstract:
A current modulation device (1) is comprised of a fixed stator (4) which has at least one annular signal track (5) with an axis (Z-Z) and whose potential varies circumferentially on a periodic basis as well as a plurality of at least two collector tracks (6 and 7) which are each connected to a respective output terminal (A or B); and a rotor (3) adapted to be coupled to a rotary driving body rotating about the axis, comprising output brushes (10 and 11) of equal number as the collector tracks and each adapted to sweep one respective collector track, as well as input brushes (8, 9) of equal number as the output brushes, each input brush being electrically collected to a respective output brush and being adapted to sweep said annular signal track, said input brushes being so arranged as to take, during the rotation of the rotor with respect to the stator, potentials presenting a given electric phase-shift.
Abstract:
A method for producing a line having variable stiffness over part of its length, and a related element allowing the stiffness thereof to be varied. The element is built in during manufacture of the line or placed around it at a later stage, and consists of sublayers of a composite material wherein at least one component of the fibre directions is parallel or at a slight angle to the pipe axis, said layers tapering off towards the end.
Abstract:
A satellite comprises at least one surface (4, 5) intended mainly for exposure to solar radiation and extending away from the satellite in a predetermined direction (Y), an on-board computer (8) having connected thereto an attitude sensing system (7), an orbit control system for imparting thrust to the satellite along predetermined axes, and an attitude control system. Said satellite further comprises a device (6') for controlling the tilt of said surface in parallel with a plurality of planes containing said predetermined direction (and therefore particularly in parallel with the plane of a solar panel forming said surface). Said tilt control device is controlled by said on-board computer. Said tilting can generate a moment of pitch or relocate the centre of gravity onto the axis of the orbit control system.
Abstract:
An articulated panel (12) formed of two substantially planar elements (14) interconnected by hinges (16) is designed so that the axes of the hinges, which are rectilinear when the panel is folded and during deployment, take a shape which is not rectilinear, for example an arc of a circle at the end of the deployment. The panel is thus locked in the deployed position. Conveniently, the deformation of the axis is obtained by giving the elements (14) a natural camber when at rest, said camber being cancelled by applying a prestress when the panel is folded back. Such a panel may be in particular a solar generator for an artificial satellite.
Abstract:
The method is of the type wherein the carbon (3) is brought in contact with a solution (2) of an amino compound in a bipolar solvent by polarizing it positively with respect to a cathode (5). According to the invention, the solvent is an organic compound, preferably aprotic, with high anodic oxidation potential, and the solution is substantially free of water.
Abstract:
Method and device for determining the position of a movable member (M) by means of optical elements integral in the displacement with the movable member and presenting optical properties which vary according to the displacement of said movable member. According to the invention, at least two optical elements (1 and 2) are associated to said movable member (M), which article elements present each, for an incident light beam which traverses them, an optical density varying according to a known law in parallel to said displacement; a common incident light beam is directed to said optical elements (1 and 2); the power of light beams respectively transmitted by said optical elements is measured; from the thus measured transmitted light powers, a magnitude R, of the form R = K.x is calculated, wherein K is a constant and x is the value of said displacement from an origin; and from the value of the magnitude R, the value x of said displacement is deduced.
Abstract:
The invention provides a method of forming sandwich materials. The area subjected to forming stresses is heated locally in such manner that the strength properties of the skin metals governing the permissible stress limits in that area are constantly monitored without the structure as a whole being subjected to oxidation.