gyromètre

CONT: Le gyroscope est un appareil capable de fournir une direction physique de référence et, corrélativement, une information de rotation angulaire, sous forme d'un écart angulaire, ou d'un angle total [...] compris entre 0 et 360 [degrés], vis-à-vis d'un référentiel absolu ou «inertiel». Le gyromètre est un appareil capable de fournir une information de vitesse angulaire, vis-à-vis d'un référentiel absolu (c'est-à-dire par rapport aux étoiles).
CONT: Tel qu'il vient d'être décrit, c'est-à-dire avec rappel élastique et amortissement visqueux [...] [le gyroscope à 1 axe] se comporte comme un gyromètre (rate gyro), c'est-à-dire un capteur de rotation instantanée absolue.

DEF: A gyroscope that is suspended in just one gimbal whose bearings form its output axis and which is restrained by a spring; rotation of the gyroscope frame about an axis perpendicular to both spin and output axes produces precession of the gimbal within the bearings proportional to the rate of rotation.
CONT: Gyrometers and gyroscopes. Gyrometers measure the angular velocity. Such measurement is based on the measure of Coriolis forces for a mobile in linear motion, when an additional rotation occurs... Gyroscopes are made of a solid body with high angular velocity around an axis of symmetry ... which induces a high angular stability in presence of perturbations. Such a device is used to preserve a fixed inertial orientation, while the rest of the system in motion. It must be noted that both devices provide an information about angular velocity. The first device output is the instantaneous angular velocity, while the second device output is the integration of the angular velocity during a period of time. Angular position information can be computed from gyrometers output by integration, while angular velocity information can be computed from gyroscopes output by derivation.