Abstract: System for controlling a plasma torch generating high power, including a rectifier feeding said torch; a circuit feeding said torch with plasma-generating gas, controlled by a regulating valve; and a controller for controlling the rectifier and the valve in order to control the arc current and the plasma-generating gas flow rate. The valve is actuated by an electropneumatic positioner associated with a pneumatic flow amplifier, the controller receives measurements of the arc voltage and arc current and delivers to the rectifier and to the electropneumatic positioner respectively, arc current and plasma-generating gas flow rate reference values adapted to produce a desired electrical reference power.

Abstract: The invention relates to a successive-actuation device of the type including at least one pyrotechnic cord and a trigger for actuating the operation thereof. Advantageously, the invention contains at least one element made from a shape-memory alloy having two stable states and disposed along the pyrotechnic cord, the element being capable of actuating a subsequent operation when it passes from one of its two stable states, for which the element occupies a neutral position, to its other stable state for which is occupies an active position, under the action of the heat generated by the pyrotechnic cord after triggering.

Abstract: A sheath for insulating a volume that optionally contains an object is made of a resilient material and it has a join plane which is shaped to constitute a baffle.

Abstract: A method of manufacturing a protective sheath made of laminated material based on fibers impregnated with resin, the method making use of a cylindrical draping mandrel, wherein:at least two longitudinal elements are provided on the mandrel to project from the periphery thereof, which elements are disposed substantially along diametrically opposite generator lines of the mandrel, dividing the mandrel into two longitudinal semicylindrical portions;a first sheet of flexible laminated material is placed on one of the semicylindrical portions of the mandrel, with the longitudinal margins of the sheet overlying the longitudinal elements;a second sheet of flexible laminated material is placed on the other semicylindrical portion, with the longitudinal margins thereof overlying the longitudinal margins of the first sheet and the projecting longitudinal elements;the first and second sheets are pressed against the outside surfaces of the semicylindrical portions by means of a pressure difference;both sheets are hardene

Abstract: A device for elastic coupling between two parts, especially the principal transmission box and the fuselage of an aircraft with rotating wings, such as a helicopter, includes first and second inner and outer tubular bodies, and an elastic connection, housed in the annular space existing between the first and second bodies and coupling the first and second bodies in a leaktight fashion. The annular space is separated by the elastic connection into first and second chambers filled with a liquid, the first and second chambers being in communication with the inside of the first body. On the inside of said first body, there is a liquid distributor provided with an elastic damping connection and including two pistons, which are coupled by a piston rod and separated from each other by the distance separating orifices in the first and second chambers.

Abstract: A scanning method and apparatus for an opto-electronic camera having a wide field of view and high resolution, wherein:for each value given to the angle of the deflector about the first axis of rotation the square of the value of the angle of the deflector about the first axis of rotation is calculated;a correction is added to the value of the angle of the deflector relative to its rotation about the second axis of rotation, the correction being in the form of a quantity proportional to the square of value of the angle of the deflector relative to its rotation about the first axis of rotation, thereby obtaining a corrected value for the angle of rotation, thereby obtaining a corrected value for the angle of the deflector relative to the second axis of rotation; andthe deflector is positioned relative to the second axis of rotation by applying the corrected value of the angle of the deflector.

Abstract: A plasma torch includes two tubular coaxial electrodes, at least one of which is axially movable between an operating position in which the movable electrode is spaced from the other electrode and an initiating position in which the movable electrode is in contact with the other electrode, thus establishing an electric short circuit so as to generate an electric arc upon rupture of the electric short circuit hen the mobile electrode is brought back to its operating position. Each electrode is contained in a support provided with a cooling circuit, through which a cooling fluid circulates. The cooling circuit associated with the movable electrode is provided with a seal which permits the electrode to be moved without creating any leaks in the cooling circuit.

Abstract: An airborne system is disclosed for determining the position of an aerial vehicle. According to the invention, a first memory is provided containing the general characteristics of different types of discrete landmarks and a second memory containing the geographic position of such landmarks on the ground to be flown over, a device for extracting, from the signals delivered by sensitive means, the general characteristics of said different types of discrete landmarks located on the ground being flown over, and a device for computing from the signals delivered by said sensitive means the relative positions of said vehicle with respect to said recognized landmarks, which it feeds to Kalman filter means.

Abstract: A method and a system for enabling high accuracy measurements to be obtained of the location of a plane separating two media of different densities by using the Compton effect, and application thereof to measuring the thicknesses of layers. A measurement assembly constituted by a transmitter and a receiver of X-rays or gamma rays which are focused in emission and in reception irradiates an elementary volume of said media, and is displaced perpendicularly to the plane between said media, and a fifth signal is calculated representative of the extent by which the derivative of the detected signal relative to the displacement exceeds a threshold, after which the barycenter of displacements corresponding to the most recent sequence of said same-sign fifth signals is calculated, with the displacements being weighted by the corresponding one of said fifth signals.

Abstract: A system for reducing the forces applied to the wings of an aircraft in flight includes an accelerometer for measuring the vertical acceleration of the aircraft and generators for generating signals to control the aerodynamic surfaces in the wings of the aircraft as a function of the acceleration measured by the accelerometer. The control signal generator is not activated except when the vertical acceleration exceeds a predetermined value.

Abstract: Applicator device for a laying machine with mobile head, for laying a composite material tape on a surface of application, said device comprising a rotary application roller carried by a mount fixed to said mobile head which applies said roller against said application surface and which advances said roller transversely to its axis of rotation so that while rolling it applies said tape on said application surface.According to the invention, this device is characterized in thatsaid rotary application roller comprises a resiliently flexible shaft deformable under flexion and a cylinder of resiliently compressible material fast with said shaft,each end of said shaft is connected to said mount by an end bearing, andat least one intermediate bearing is provided between said end bearings for connecting said shaft to said mount.

Abstract: An ultrasonic percussion device uses an ultrasonic generator attached to one end of a wire by a linking assembly which includes a radially elastically deformable sleeve (7) receiving the end of the wire and provided with a conical flared section (7B); a hole (8) provided in a member (9) integral with the generator and into which the sleeve is able to be introduced, the conical section (7B) of the sleeve (7) coming into contact with a complementary conical wall (8B) provided in the hole, and a clamping element (10) able to cooperate by screwing with the member (9) and to act against the sleeve (7); the device is particularly useful for destroying atheromata in clogged arteries.

Abstract: The system may be used, for example, to initialize the inertial unit of a missile from the inertial unit of a vehicle carrying the missile. According to the invention, a servo-control circuit is provided for slaving data in the missile inertial unit on data from the carrier inertial unit, together with a Kalman filter connected in parallel with said servo-control circuit and designed to identify harmonization errors between the two inertial units.

Abstract: A device for controlling, in association with a stop valve, the gas stream delivered by a pressurized gas reservoir, whose casing is provided with an opening so that the inside of said reservoir may be connected to the outside. A cylinder is divided into a first chamber and a second chamber by a piston. The first chamber is in communication with the opening in the casing and includes an orifice which can be connected with the stop valve. A core is connected to the piston on the side thereof turned towards the first chamber. The core cooperating with the orifice so as to form a variable flow section as a function of the position of the piston in the cylinder. A passage with a non-return valve establishes communication between the first and second chambers of the cylinder. A controllable locking device is capable of locking the piston in the cylinder.

Abstract: A plasma torch includes two axially spaced tubular electrodes and an electromagnetic coil for rotating an electric arc formed between the electrodes. Each electrode is held in a support, at least one support containing a cylindrical cooling chamber through which an electrically nonconductive cooling fluid can be passed. The electromagnetic coil divides the cooling chamber into two annular spaces which are interconnected at one end.

Abstract: A pitch control system for an aircraft flying at a Mach number greater than 0.7 and including a horizontal plane that is adjustable in deflection and air brakes having a nose-down effect. According to the invention, the system comprises:first means providing the aerodynamic incidence (.alpha.) of said aircraft at each instant;second means for generating a nose-down first command (.DELTA.iHC) for said adjustable horizontal plane when said aerodynamic incidence is greater than said first threshold (.alpha.0), the amplitude of said first command being such that if said adjustable horizontal plane were to take up the corresponding position instantaneously, it would compensate the increase in the nose-up effect on said aircraft due to the way in which said aerodynamic pitching couple varies above said first threshold;third means for generating a signal (.DELTA.

Abstract: A locking system is disclosed comprising two elements connected mechanically together so as not to be able to move apart, as well as a cam mounted for rotation on the first of said elements and having a contact surface pressing against a bearing face carried by the second of said elements.According to the invention, said contact surface of said cam has at least approximately a profile in the form of a logarithmic spiral, whereas said bearing face is flat and said cam may rotate about a hub on the axis of which is located the origin of said logarithmic spiral, said hub being mounted for rotation on said first element about an off-centered axis of rotation opposite said contact surface of said cam. Resilient means are provided for rotating said cam in a first direction such that said contact surface moves towards said bearing face.

Abstract: A system for maintaining in a folded position a set of elements that are hinged to one another and to a structure (e.g. solar panels on a spacecraft), which elements are capable of occupying either said folded position in which said elements form a stack, or else a deployed position in which said elements are in end-to-end alignment, said system comprising:a retaining member passing through said elements in the folded positive and connected by a first one of its ends to said structure and bearing via a second one of its ends against the outermost element of said set;locking means for locking said retaining member in the folded position of said elements; andcontrol means for unlocking said locking means and releasing said retaining member, thereby enabling said set of elements to pass from the folded position to the deployed position.

Abstract: A method and device are disclosed for forming reinforcement elements from resistant fibers distributed along three dimensions, in which method, a continuous fiber is introduced in a substrate resting on a support formed of such fibers crossed in at least two directions, by stitching, from the free face of said substrate opposite said support by means of a needle driven with a reciprocal movement, a relative movement being in addition generated between said support and said needle so that said continuous fiber is formed inside said substrate of a succession of consecutive segments forming a zig-zag line.The invention is remarkable in that:said needle is curved and imposes on each segment of said continuous fiber a similar curved form; andthe reciprocal movement of said curved needle occurs while rotating about an axis perpendicular to the plane of said needle and disposed on the concave side thereof.

Abstract: Pressurized gas tank comprises a casing provided with an opening communicating with an orifice and connecting the inside of the tank with the outside. Gas flow through the orifice is controlled by a flow control valve. The casing is elastically deformable in response to the gas pressure contained in said tank (1). Deformation of the tank is transmitted to the flow control valve to control the flow of gas therethrough.