TERMIUM Plus^®

Record 1,  Textual support,  English

Record number: 1, Textual support number: 1 OBS

Mechanical gyros(Dynamically Tuned Gyro, DTG) consist of a rotating body suspended dynamically tuned on low friction gimbals. The rotating mass attempts to keep the orientation of the rotation axis constant and thus creates a torque on the suspension when the system is turned. The torque is proportional to the rate.  2, record 1, English, - dynamically%20tuned%20suspension

Record 1,  Textual support,  French

Record number: 1, Textual support number: 1 CONT

Équations de la gyroscopie [...] Suspension dynamique accordée [...] le principe : Les paliers des articulations S1-S2 et S2-S3 ne sont plus des roulements, mais remplacés par [des] joints de Hooke ou encore des barres de torsion élastiques. Un calcul complexe montre qu'à une vitesse précise dite d'accord, la raideur des joints est compensée [...] par le couple des forces d'inertie centrifuge et la suspension ne présente plus alors aucune rigidité. Les débattements de la toupie, en orientation, sont limités à quelques degrés. La condition d'accord définissant la vitesse correcte relie les caractéristiques des barres de torsion et un moment d'inertie particulier de l'anneau interne. On l'appelle la condition de tuning et c'est ce qui donne à la technique le nom de gyroscope accordé.  1, record 1, French, - suspension%20dynamique%20accord%C3%A9e

Record 1,  Textual support,  Spanish

Record 2,  Textual support,  English

Record number: 2, Textual support number: 1 CONT

The attitude heading reference system provides attitude gyro, directional gyro(compass) and 3-axis rate/accelerometer data to the following aeroplane systems in EFIS [electronic flight instrument system] equipped aircraft : Primary flight and multi-function displays; Weather radar system; Automatic Flight Control System; Ground Proximity Warning System; Traffic Alert and Collision Avoidance System; Stall Protection System; Fuel System; Flight Data Recorder; Body Rates and Linear Acceleration Data to the flight control system.  13, record 2, English, - attitude%20and%20heading%20reference%20system

Record number: 2, Textual support number: 2 CONT

Crossbow [TM] Technology, Inc. ... introduced its new AHRS500GA solid-state attitude and heading reference system for general aviation ... Crossbow’s AHRS500GA is a strap-down subsystem that delivers heading measurements with dynamic accuracy of +/- 2.0 and static accuracy of +/- 1.5. Attitude accuracy is less than +/- 0.5 degrees (static) and +/- 2.0 degrees (dynamic). Range is +/- 180 degrees. The system features the industry’s highest performing sensors, including advanced MEMs accelerometers and rate gyros that provide much higher reliability than traditional spinning mass gyros.  14, record 2, English, - attitude%20and%20heading%20reference%20system

Record number: 2, Textual support number: 1 OBS

heading and attitude reference system; HARS: term and abbreviation officialized by the Aeronautical Terminology Standardization Committee (ATSC) - Helicopters.  15, record 2, English, - attitude%20and%20heading%20reference%20system

Record 2,  Textual support,  French

Record number: 2, Textual support number: 1 CONT

Une centrale moderne d'attitude et de cap [...] ressemble beaucoup à une centrale inertielle de navigation qui ne fournirait que les assiettes et le cap, et dont les gyroscopes et les accéléromètres seraient de performances modestes : 1 à 10 degrés par heure pour les gyroscopes et quelques millièmes de la pesanteur pour les accéléromètres. La centrale d'attitude et de cap peut être à cardans ou à composants liés [...] et utiliser des gyroscopes mécaniques ou des gyrolasers.  2, record 2, French, - centrale%20d%27attitude%20et%20de%20cap

Record number: 2, Textual support number: 1 OBS

centrale de cap et de verticale; AHRS : terme et abréviation uniformisés par le Comité d'uniformisation de la terminologie aéronautique (CUTA) - Opérations aériennes.  9, record 2, French, - centrale%20d%27attitude%20et%20de%20cap

Record number: 2, Textual support number: 2 OBS

centrale de cap et d'attitude : terme uniformisé par le Comité d'uniformisation de la terminologie aéronautique (CUTA) - Hélicoptères.  10, record 2, French, - centrale%20d%27attitude%20et%20de%20cap

Record 2,  Textual support,  Spanish

Record 3,  Textual support,  English

Record number: 3, Textual support number: 1 CONT

Ring laser gyro... The mechanical structure integrity of the gyro is based on a 1. 2 X1. 2 meter block of zerodur. The zerodur is a glass ceramic material with a thickness of 180 mm weighing approximately 600 kg. The block has four 1-meter longitudinal bores provided for the laser beam paths. Folding mirrors are mounted at each of the four corners of the block. This forms a closed square resonator in which the laser beams can travel in both directions. The block was produced by Zeiss Glaswerke of Mainz, Germany. At Zeiss the machining process included cutting the gyro body edges in preparation for the mounting of the folding mirrors. The surfaces for the mirror mounting are optically polished allowing the folding mirrors to be attached directly to the zerodur by optical contact rather than by bonding.  3, record 3, English, - gyro%20body

Record number: 3, Textual support number: 2 CONT

[Ring laser gyro] The gyro body is constructed from a solid block of quartz(Zerodur) to eliminate any mechanical distortion of the block by linear or rotational acceleration and prevent outgassing.  4, record 3, English, - gyro%20body

Record 3,  Textual support,  French

Record number: 3, Textual support number: 1 CONT

[...] le gyrolaser est un contraignant : parmi les principales contraintes, notons que : la cavité optique doit être de dimension bien ajustée, pour obtenir en sortie une puissance lumineuse suffisante : cela nécessite un asservissement en longueur, l'un des miroirs étant mobile, de position ajustable par piézoélectricité, pour que cet asservissement soit efficace, le socle doit être réalisé en Zérodur, une vitrocéramique de coefficient de dilatation thermique quasiment nul [...]  1, record 3, French, - socle

Record number: 3, Textual support number: 2 CONT

Pour l'utilisation sur les centrales inertielles, il s'est révélé nécessaire de développer des gyroscopes présentant une dérive pratiquement négligeable. Or la cause principale de cette dérive réside dans les frottements qui s'exercent sur le corps du gyroscope, dont la vitesse de rotation dépasse 20 000 tr/min.  2, record 3, French, - socle

Record 3,  Textual support,  Spanish

Record 4,  Textual support,  English

Record number: 4, Textual support number: 1 CONT

... for a mechanically dithered RLG [ring laser gyro], non-linearities(sidebands) appear in the input-output scale factor curve for an input rotation rate which is a harmonic of the dither frequency... There are two disadvantages to dithering. One is that the rotation rate periodically passes through zero where lock-in occurs. This results in a "random walk" angular position error. The other is that the vibration of the gyro body may affect other components or the gyro may be affected by other vibration sources. The laser gyro need not be mechanically dithered. The same result may be achieved by optical devices.  1, record 4, English, - mechanically%20dithered

Record number: 4, Textual support number: 1 OBS

dither: To periodically tilt from side to side.  2, record 4, English, - mechanically%20dithered

Record 4,  Textual support,  French

Record 4,  Textual support,  Spanish

Record 5,  Textual support,  English

Record number: 5, Textual support number: 1 DEF

Gyro that tends to compensate the motion of aircraft [or similar body] with reference to the longitudinal(roll) axis.  5, record 5, English, - roll%20rate%20gyroscope

Record number: 5, Textual support number: 1 CONT

Roll-rate gyro. The roll-rate gyro is less sensitive than the P [pitch] and Y [yaw] rate gyros. Roll-rate control limits fast roll rates during boost, before roll stabilization takes place. This gyro damps the missile’s rolling oscillations about the normal flight position.  2, record 5, English, - roll%20rate%20gyroscope

Record number: 5, Textual support number: 2 CONT

The gyropilot, commonly called an automatic pilot (q.v.), consists basically of three devices, each of which detects disturbances of the aircraft in one plane and corrects for these disturbances by moving the appropriate control ... The roll disturbance is detected by a roll rate gyroscope and by a roll angle pendulum, which senses displacement.  1, record 5, English, - roll%20rate%20gyroscope

Record number: 5, Textual support number: 1 OBS

See record "gyrometer; rate gyro.  6, record 5, English, - roll%20rate%20gyroscope

Record 5,  Textual support,  French

Record number: 5, Textual support number: 1 CONT

Le TGV pendulaire est un train de haute technologie qui offre un agrément de voyage et une vitesse sur rail inégalés à ce jour. [...] L'Unité de Contrôle de Pendulation (UCP) est implantée sur une carte bi-processeurs composée d'un processeur I960 et d'un processeur de traitement de signal TMSC31 cadencé à 32 MHz et possédant 512Ko de mémoire vive. [...] Le TMS est consacré d'une part à l'échantillonnage à 1 KHz des données capteurs provenant de l'accéléromètre et des gyromètres de roulis et de lacet situés sous le bogie de tête, et d'autre part à l'implémentation du module loi de commande à une fréquence de 100 Hz.  2, record 5, French, - gyrom%C3%A8tre%20de%20roulis

Record number: 5, Textual support number: 1 OBS

Voir la fiche «gyromètre».  3, record 5, French, - gyrom%C3%A8tre%20de%20roulis

Record 5,  Textual support,  Spanish

Record 6,  Textual support,  English

Record number: 6, Textual support number: 1 CONT

... for a mechanically dithered RLG [ring laser gyro], non-linearities(sidebands) appear in the input-output scale factor curve for an input rotation rate which is a harmonic of the dither frequency... There are two disadvantages to dithering. One is that the rotation rate periodically passes through zero where lock-in occurs. This results in a "random walk" angular position error. The other is that the vibration of the gyro body may affect other components or the gyro may be affected by other vibration sources. The laser gyro need not be mechanically dithered. The same result may be achieved by optical devices.  1, record 6, English, - mechanically%20dithered%20RLG

Record number: 6, Textual support number: 1 OBS

dither: To periodically tilt from side to side.  4, record 6, English, - mechanically%20dithered%20RLG

Record 6,  Textual support,  French

Record 6,  Textual support,  Spanish

Record 7,  Textual support,  English

Record number: 7, Textual support number: 1 CONT

This is normally done using dither, the application of a large amplitude sinusoidal excitation to the gyro body.  1, record 7, English, - large%20amplitude%20sinusoidal%20excitation

Record 7,  Textual support,  French

Record number: 7, Textual support number: 1 CONT

Concrètement, la solution la plus courante consiste à appliquer au corps du gyro une excitation sinusoïdale de grande amplitude qui le fait trembler.Ce tremblement correspond à un taux de rotation d'environ 100 o/s que l'on compense artificiellement au niveau du capteur pour que celui-ci mesure le taux réel de rotation.  1, record 7, French, - excitation%20sinuso%C3%AFdale%20de%20grande%20amplitude

Record 7,  Textual support,  Spanish

Record 8,  Textual support,  English

Record number: 8, Textual support number: 1 CONT

As the gyro rotates, its body rotates relative to the standing wave, so angular rotation can be measured by observing the changes in the detector outputs.  1, record 8, English, - detector%20output

Record 8,  Textual support,  French

Record number: 8, Textual support number: 1 CONT

Si l'on fait tourner le gyro, son boîtier tourne par rapport à l'onde stationnaire qui reste fixe dans l'espace, de sorte que l'on peut mesurer la rotation angulaire en observant les variations du signal de sortie des détecteurs.  1, record 8, French, - signal%20de%20sortie%20du%20d%C3%A9tecteur

Record 8,  Textual support,  Spanish