摘要:
An airborne gravity-based transducer is disclosed as two embodiments with similar physical structures but different operating principles. The first design includes a particle acting as an active interface characterized by internal vibrations relating to its de Broglie wave, a resonant cavity for trapping the particle, and a phonon-wave source wherein the de Broglie and phonon waves interact over a junction area. In the second design, mechanical displacements between the transducer elements can be monitored through electromechanical transduction.
摘要:
An airborne gravity-based transducer is disclosed as two embodiments with similar physical structures but different operating principles. The first design includes a particle acting as an active interface characterized by internal vibrations relating to its de Broglie wave, a resonant cavity for trapping the particle, and a phonon-wave source wherein the de Broglie and phonon waves interact over a junction area. In the second design, mechanical displacements between the transducer elements can be monitored through electromechanical transduction. Both designs include a power source and a biasing circuit for producing an electrical current across the junction, and a sensing system for measuring voltage. Both designs are capable of cancelling slowly-varying gravitational acceleration due to dynamic interaction in motion with the gravitational field and responding to small-scale gravity anomalies. Furthermore, a number of cascade design configurations based on the basic design are also disclosed in order to enhance the transducer performance. The transducer can be utilized in hydrocarbon exploration to provide information on areas conducive to fluid entrapment in the sedimentary column.
摘要:
An apparatus for measuring gravitational force is provided having at least one optomechanical oscillator, the at least one optomechanical oscillator having an initial resonance, and a second resonance when displaced by gravitational force; and at least one photonic crystal having at least one cavity coupling optical and mechanical degrees of freedom of the oscillator.
摘要:
The present invention provides a method of tuning properties of a gravity gradiometer for measuring components of the gravity gradient tensor. The gravity gradiometer comprises a pair of first and second transversely arranged sensor masses that are arranged for movement about an axis and relative to each other in response to a gravity gradient. The gravity gradiometer further comprises first and second capacitors for sensing and influencing the movement of the first and second sensor masses. The method comprising applying a bias voltage to at least one of the capacitors for generating an electrostatic force which acts on one of the sensor masses and thereby influences the movement of that sensor mass.
摘要:
A gravity gradiometer and method for forming a pivot flexure web for a gradiometer is disclosed. The gradiometer has measurement bars 41, 43 supported in housings 45 and 47 and transducers 71 for measuring movement of the bars to provide an indication of the gravity gradient tensor. The bars 41, 43 are mounted on flexure webs. The webs are formed in separate elements to the housing and bars.
摘要:
Apparatus for measuring gravitational fields comprising a superconducting string (1) fixed at both ends and forming part of a closed superconducting loop inductively coupled to two driving solenoids (L.sub.d1, L.sub.d2). Displacement of the string in response to a gravitational field is sensed by two magnetic flux transformers each comprising a signal coil and two pick-up coils ((L.sub.p1, L.sub.p2). Pairs of pick-up coils lie in two perpendicular planes providing two independent channels of measurements. The two arms of each flux transformer are balanced to convert only the amplitudes of the string's antisymmetric natural modes into an output voltage. The output voltage of each channel is used to produce a feed-back current distribution (L.sub.y1, L.sub.y2) proximate and parallel to the string. By adjusting the feed-back current, the effective relaxation time and resonant frequency of the first antisymmetric mode of the string can be adjusted, while leaving the symmetric modes unchanged, thus increasing the apparatus' sensitivity to gravity gradients.
摘要:
A mechanical linear guide for making a body move in an axial direction, comprising a system which is preferably made up of reinforced leaf springs and/or hole-type hinges, and which is rotationally symmetrical about an axial direction and mirror-symmetrical about a plane perpendicular to the axial direction. The system is connected to a fixed base at six points (A, D, I, L, M, P), and a body (18) is suspended between two points (F, G) in such a way that it can carry out only movement in the axial direction, and not in the lateral direction.
摘要:
AN AMPLIFIER PARTICULARLY FOR USE WITH A PIEZOELECTRIC TRANSDUCER BONDED TO A VIBRATING MASS. THE CRYSTAL IS CONNECTED IN THE INPUT CIRCUIT OF THE AMPLIFIER, AND THE MASS AND CRYSTAL ARE EQUIVALENTLY REPRESENTED BY A SERIES TUNED CIRCUIT, AT RESONANCE. A FEEDBACK PATH OF HIGH RESISTANCE IS PROVIDED IN THE AMPLIFIER, AND FEEDBACK IS NEGATIVE, SO THAT THE FEEDBACK RESISTANCE AND THE AMPLIFIER INPUT IMPEDANCE LARGE NEGATIVE FEEDBACK OCCURS, WHILE FOR LOW INPUT IMPEDANCE SMALL NEGATIVE FEEDBACK OCCURS, DUE TO THE ACTION OF THE DIVIDER. THE EFFECTIVE Q OF THE SERIES TUNED CIRCUIT IS THUS INCREASED. THE OUTPUT CIRCUIT OF THE AMPLIFIER MAY BE, IF DESIRED, A LOW Q TANK CIRCUIT. IF R2 IS THE FEEDBACK RESISTANCE AND R THE EFFECTIVE RESISTANCE OF THE SERIES TUNED CIRCUIT GAIN CAN BE
摘要:
Optomechanical device for actuating and/or detecting movement of a mechanical element, in particular for gravimetric detection. It includes a support with a mechanical element anchored to the support which is designed to move relative to the element, and a device for actuating and/or detecting movement or of variations in frequency of movement of the element. A portion of the device is arranged beneath at least part of the element, between the element and the support. The device includes a fixed optical device with at least one optical waveguide arranged beneath all or part of the element at a determined distance from the element, and which is designed to propagate at least one optical wave having a given wavelength designed to interact with the element. The optical waveguide is at a determined distance from the mechanical element so that the evanescent field of the optical waveguide interacts with the mechanical element.