Showing papers by "Matra published in 1980"

Process and apparatus for stripping insulated wires

Abstract: For locally stripping an electric wire, the wire is maintained in a guide, the insulating material is cut with rotary knives over a fraction only of its thickness and the residual insulation material is broken by pulling after the knives have been stopped. An apparatus for carrying out the process has a stripping head supporting a wire-guide, provided with a drive motor for rotation about the axis of the guide and carrying knives radially movable between an inner and an outer position. An electromagnetically controlled wire-clamping system is used for axially moving the wire.

Active nutation control system for space vehicle

Abstract: An active nutation control system for a space vehicle spinning about a geometric axis has thrusters for creating an external torque about an axis transverse to the first. The amplitude of the nutation and its phase in relation with the spinning movement are detected. A control arrangement receives signals from the nutation detectors, computes the changes in the angular direction of the angular momentum of the vehicle caused by thruster activation and energizes the thrusters when contemporaneously the amplitude of the nutation movement is greater than a predetermined threshold, the phase corresponds to maximum efficiency of said thrusters in reducing nutation momentum of the vehicle or at least does not increase it.

Study of an integrated attitude sensing system and development of a prototype

Abstract: A gyro based attitude control system is described for geostationary satellites requiring high accuracy (0.05 deg. in pitch/roll, 0.1 deg. in yaw). The system is based on high quality strapdown rate integrating gyro updated by earth and sun sensors via an estimation procedure implemented in an on-board digital computer. Two system mechanizations are studied: – A single yaw gyro with digital sun sensor updates for yaw reference and two axes infra red earth sensor for pitch and roll, – two gyros in gyro-compass mode with sun sensor and roll earth sensor updates for roll/yaw and earth sensor for pitch. Control system is based on reaction wheels (normal pointing) and hydrazine thrusters (station keeping and momentum undoad). The calibration filter is a discrete KALMAN filter that estimates gyro error sources. An efficient approach permits separation of low frequency and high frequency sources. In the calibration filter only low frequency error sources are estimated : gyro integral error and gyro drift. For the purpose of real 3-axis dynamic performance test of the two concepts, a representative prototype of envisaged future systems of attitude sensing and filtering has been developped. During this system test, control loops, spacecraft dynamics and kinematics are done by a computer, driving an air bearing platform (servoed table) on which all detectors are mounted. The key design features of the prototype (optical sensors and gyropackage) are detailed, with emphasis on gyro configuration selection, gyro rebalance loop, ground effects reduction concepts, sensors simulation. System test implementation and procedures are described, to provide necessary background to results announced during conference. As a conclusion, a brief discussion about interest and future developments of modular attitude estimator systems is made.

Foam material body for a mattress, and element of furniture provided with same

Abstract: A foam material body for a mattress has a core member having two supporting surfaces and provided with a plurality of recesses in each of said surfaces, wherein each of the recesses has an initial recess portion which is open at a respective one of the supporting surfaces, two deeper recess portions extending from the initial portion inwardly from the same and away from one another, and two narrow recess portions each connecting the initial recess portion with a respective one of the deeper recess portions. Each of the recesses has a depth which is smaller than half the thickness of the core member.

Foamed body for a mattress

Abstract: A mattress (17) includes a foam body (21) having a core (25) and two outer layers (23). The core (25) is provided on its upper and lower sides with incisions (27). These have a in a bearing surface (25a) opening into the top portion (27a) and then in two partial cuts (27b) are being branched, each subsequent in which the initial portion (27a) region has a restriction (27c). Each notch (27) delimits, together with the respective bearing surface (25a) has two lips (25b), between the free ends (25c) is a through the initial portion (27a) formed, free space is available. delimit two on the top and bottom of the core (25) existing, opposing notches (27) between them a web (25g), wherein the boundary surfaces (25d) for part form approximately convex circular arc. When bending of the mattress (17), the lips (25b) to the bars (25g) around slide. When compressive loads lips (25b) are in the range derverengungen (27c) of the webs (25g) supported.

Multiple axle aligning system for heavy vehicle - uses laser and set of mirrors cooperating with adjustable coordinate measurement table

Abstract: A device for measuring and aligning vehicle axles has a light source sending a beam parallel to the vehicle longitudinal axis. There is a mirror directed parallel to the axle, and a coordinate measurement table with an opening through which the beam passes. The device enables simple measurement of all axles of a multiple axle vehicle including articulated lorries with trailers and ominibusses with single axle trailers. It uses a narrow light beam and the table has a device permitting adjustment of the distance between it and the axle being measured.

Un Stereorestituteur Analytique : Le Traster 77

Abstract: The fundamental characteristics of analytical stereoplotters compared to the analog stereoplotters is their facility to use them and the versatility given by the on-line of a mini-computer. Analog stereoplotters, even those classified universal, are generally designed at the beginning for cartographic plotting from aerial photographies. Few of them have the capability to be used in non cartographic field such as biostereometrics applications. Analytical stereoplotters are usable in all kind of restitution, monoculary or stereoscopically. The main particularity of TRASTER, the analytical stereoplotter built by Matra, is its stereo viewing system obtained by an optical projection in polarized light of the photographies in place of the conventionnal binocular system. This feature increases the operator comfort, gives a better facility of the stereophoto-grammetry adaptation to not confirmed operators and allows the stereo view by several people in the same time. Thanks to the incorporated computer, specific softwares can be easily adapted to Traster. Restitution of stereopairs are possible in on-line mode on the drafting table. Three dimensional coordinates of objects to be plotted can be stored in numerical form for further processing.© (1980) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.