Abstract: The gyrometer comprises a cavity filled with a fluid in the form of a body of revolution having an axis coinciding with the axis of a rotation to be measured. An excitation transducer and a measuring transducer are disposed on the wall of the cavity in a same cross section and offset at an angle of 90.degree.. The excitation transducer excites a first acoustic resonance mode of the cavity and the measuring transducer measures a second mode of resonance induced by Coriolis forces when the cavity is subjected to the rotation to be measured. Such a gyrometer, less sensitive to mechanical embodiment inaccuracies, is assembled on, a moving body, for example, in order to measure its speed(s) of rotation.

Abstract: The invention relates to a gyrometer, without material rotor, of the type using the Coriolis forces on the particles of a fluid contained in a resonant cavity. It comprises, in addition to the conventional excitation and detection unit, a unit for effecting servo-control in phase of the longitudinal acoustic oscillation in the cavity and employs a weak coupling mode between exciter and cavity. The gyrometer according to the invention overcomes the variations in length of the cavity and the fluctuations in the speed of propagation of the oscillations in the fluid as a function of the temperature.

Abstract: Disclosed is an apparatus for measuring the aerodynamic parameters of an airflow around an aircraft. A streamlined body is rotatably mounted in the airflow such that it aligns itself freely with the flow. Total and static pressure pick-off apertures are provided in the body. The measurement of the true angle of incidence is obtained from two distinct measurements. A first measurement mechanically provides the orientation .alpha.m of the streamlined body relative to the aircraft and the other provides the aerodynamic pressure orientation .alpha.a of the same streamlined body relative to the airflow. The true angle of incidence .alpha. is then determined by summing .alpha.m and .alpha.a.

Abstract: A device is provided comprising a circuit using the properties of a resonating cavity sensor whose resonance frequency is modified by the electric capacity variations due to the mechanical deformation of a wall under the effect of the pressure to be measured. It uses a single coaxial cable for connecting the sensor to the user circuit and the sensor, through the coaxial cable, is placed in the leg of an impedance bridge providing the value of the standing wave rate characteristic of the difference between the tuning frequency of the cavity and the frequency of an oscillator controlled by this rate.