A submersible sound system may include a housing, an end piece, an elastic membrane, an end cap affixed to the elastic membrane, and a subwoofer speaker system disposed within the housing and supported by a speaker support. A bubble sound source may be defined by the speaker support, the speaker diaphragm, an anterior end of the housing, the elastic membrane, and the end cap. The housing, end piece, and a posterior surface of the speaker support may form a sealed enclosure. The sound system may include a tuning pipe disposed between the sealed enclosure and the bubble sound source. A Helmholtz resonator may be disposed anteriorly of the speaker system. Multiple sound system may be assembled to form a cluster. The cluster may be defined by the vertices of regular polyhedron. The sound systems may be controlled to maintain the speaker systems within acceptable thermal limits.
A submersible sound system may include a housing, an end piece, an elastic membrane, an end cap affixed to the elastic membrane, and a subwoofer speaker system disposed within the housing and supported by a speaker support. A bubble sound source may be defined by the speaker support, the speaker diaphragm, an anterior end of the housing, the elastic membrane, and the end cap. The housing, end piece, and a posterior surface of the speaker support may form a sealed enclosure. The sound system may include a tuning pipe disposed between the sealed enclosure and the bubble sound source. A Helmholtz resonator may be disposed anteriorly of the speaker system. Multiple sound system may be assembled to form a cluster. The cluster may be defined by the vertices of regular polyhedron. The sound systems may be controlled to maintain the speaker systems within acceptable thermal limits.
An acoustic transducer and method of generating acoustic transmit and receive beams is disclosed. The system includes a plurality of transducer elements arranged to folio an array, where the elements are electrically connected into groups which operate at the same electrical phase, where the phases of adjacent groups of elements differ by between about 50 and 70 degrees and a beamforming circuit where the transmit and receive signals are operated with appropriate phase shifts to maintain the between about 50 and 70 degrees phase difference between adjacent groups. The resulting transducer generates transmit and receive beams that are nominally inclined less than about 30 degrees from a planar normal axis of the array.
G01S 7/52 - DÉTERMINATION DE LA DIRECTION PAR RADIO; RADIO-NAVIGATION; DÉTERMINATION DE LA DISTANCE OU DE LA VITESSE EN UTILISANT DES ONDES RADIO; LOCALISATION OU DÉTECTION DE LA PRÉSENCE EN UTILISANT LA RÉFLEXION OU LA RERADIATION D'ONDES RADIO; DISPOSITIONS ANALOGUES UTILISANT D'AUTRES ONDES - Détails des systèmes correspondant aux groupes , , de systèmes selon le groupe
An underwater active sonar system and method for measuring instrument velocity with respect to a boundary surface is disclosed. The system includes an acoustic transducer configured to transmit and receive a plurality of acoustic beams in different directions. The system also includes a processor configured to detect a boundary surface within each beam; iteratively filter received acoustic signals backscattered from the transmitted beams with an adaptive filter and associated bandwidth that is successively decreased for each iteration; and measure instrument velocity with respect to the boundary surface.
G01S 15/60 - Systèmes de détermination de la trajectoire ou de la vitesse; Systèmes de détermination du sens d'un mouvement dans lesquels l'émetteur et le récepteur sont montés sur l'objet mobile, p.ex. pour déterminer la vitesse par rapport au sol, l'angle de dérive, le trajet au sol
5.
LOW-FREQUENCY BROADBAND SOUND SOURCE FOR UNDERWATER NAVIGATION AND COMMUNICATION
An underwater sound source includes an acoustical driver, a controller of the acoustical driver, and a resonant tube acoustically coupled to the acoustical driver. The resonant tube has a pair of slotted portions, in which each slotted portion is disposed along the length of the resonant tube at a location corresponding to a node of a harmonic of the resonant tube. The sound system is configured to emit an output signal within a bandwidth defined by a dual resonance characteristic of the resonator tube. The sound source may also include a pair of coaxial tubular sleeves disposed around the resonant tube, each sleeve configured to slidably cover one of the slotted portions, and tune the resonance frequency of the tube over a wide range. At a high frequency end, when slots are uncovered, the frequency response of the resonant tube obtains a dual-resonant form.
A sound source including a first gas filled underwater resonator, a second gas filled underwater resonator connected to the first resonator, where the second resonator comprises a Helmholtz resonator, and at least one excitation member configured to excite the first resonator and the second resonator is disclosed. The first resonator is permanently tuned to produce a first resonant frequency upon excitation by the at least one excitation member and the second resonator is permanently tuned to produce a second resonant frequency upon excitation by the at least one excitation member. The first resonant frequency is different from the second resonant frequency.
G01V 1/133 - Production d'énergie sismique en utilisant des fluides comme moyens d'entraînement hydrauliques, p.ex. en utilisant des fluides à haute pression
A small aperture acoustic velocity sensor and a method for velocity measurement are disclosed. In one aspect, the disclosed technology uses spatially-shifted sub-arrays for projection and/or hydrophone receipt and cross-correlation of successive pulses to improve correlation and reduce bias. The spatial shift can be created physically by selection of groups of elements or virtually by weighting the contributions of fixed sub-arrays. Spatial modulation can be used to form a projected signal and measured spatial phase of slope across the set of sub-arrays allows correction of both long- and short-term errors. The disclosed technology uses spatial and/or temporal interpolation.
G01S 15/42 - Mesure simultanée de la distance et d'autres coordonnées
G01S 7/52 - DÉTERMINATION DE LA DIRECTION PAR RADIO; RADIO-NAVIGATION; DÉTERMINATION DE LA DISTANCE OU DE LA VITESSE EN UTILISANT DES ONDES RADIO; LOCALISATION OU DÉTECTION DE LA PRÉSENCE EN UTILISANT LA RÉFLEXION OU LA RERADIATION D'ONDES RADIO; DISPOSITIONS ANALOGUES UTILISANT D'AUTRES ONDES - Détails des systèmes correspondant aux groupes , , de systèmes selon le groupe
A sound source includes a first gas filled underwater resonator, a second gas filled underwater resonator connected to the first resonator and at least one excitation member configured to excite the first gas filled underwater resonator and the second gas filled underwater resonator, where the first gas filled underwater resonator is permanently tuned to produce a first resonant frequency upon excitation by the at least one excitation member, where the gas filled underwater second resonator is permanently tuned to produce a second resonant frequency upon excitation by the at least one excitation member, and where the first resonant frequency is different from the second resonant frequency.
G01V 1/133 - Production d'énergie sismique en utilisant des fluides comme moyens d'entraînement hydrauliques, p.ex. en utilisant des fluides à haute pression
A winch is employed for deploying a probe to a precise depth within a water column for making and recording physical measurement within such water column. More particularly, the winch rapidly unspools a line from an underway vessel, while maintaining minimal but constant line tension, as a probe, tethered to such line, descends within the water column in a "near" free-fall to a predetermined depth and then stops. The line lacks means for communicating its depth to the winch. The probe achieves a predictable descent behavior, even though it is tethered by a line to a winch onboard an underway vessel of unknown velocity and in variable weather conditions. The predictable descent behavior is achieved by maintaining a. minimal constant tension on the line within a narrow range. The descent behavior of a probe in "near" free-fall has sufficient predictability to construct an algorithm to correlate descent time with depth.
B63B 27/08 - Aménagement des équipements de bord pour l'embarquement ou le débarquement des cargaisons ou des passagers des treuils
B63B 21/66 - Apparaux de remorquage ou de poussée Équipements spécialement adaptés au remorquage sous l'eau des objets ou des navires, p.ex. carénages hydrodynamiques pour câbles de remorquage
B66D 1/50 - Dispositifs de commande automatiques pour maintenir une tension prédéterminée de la corde, du câble ou de la chaîne, p.ex. pour des cordes ou des câbles de remorqueur, des chaînes d'ancre; Commande de la tension des câbles de treuils de touage ou d'amarrage
B66D 5/00 - Dispositifs de freinage ou de détente caractérisés par leur application aux mécanismes de levage ou de hissage, p.ex. pour régler l'affalement des charges
10.
DETECTION AND CORRECTION OF WINDOW MOISTURE CONDENSATION
Condensation mitigation devices and condensation prediction/detection techniques configured to prevent window condensation with reduced power consumption are disclosed. A condensation mitigation device is configured to predict and/or detect a window condensation event. The condensation mitigation device is powered on only during such an event, and the condensation mitigation device is powered off afterwards to conserve power.
G01D 11/26 - Regards; Verres protecteurs; Scellements pour ceux-ci
G01D 3/036 - Dispositions pour la mesure prévues pour les objets particuliers indiqués dans les sous-groupes du présent groupe pour atténuer les influences indésirables, p.ex. température, pression sur les dispositions de mesure elles-mêmes
H05B 3/84 - Dispositions pour le chauffage spécialement adaptées à des surfaces transparentes ou réfléchissantes, p.ex. pour désembuer ou dégivrer des fenêtres, des miroirs ou des pare-brise de véhicules
G01N 21/47 - Dispersion, c. à d. réflexion diffuse
G01N 21/94 - Recherche de souillures, p.ex. de poussières
G01N 27/12 - Recherche ou analyse des matériaux par l'emploi de moyens électriques, électrochimiques ou magnétiques en recherchant l'impédance en recherchant la résistance d'un corps solide dépendant de la réaction avec un fluide
A laser Doppler velocimeter uses self-mixing amplification of backreflections from scatterers below the surface of a flow. A time domain signal is divided into segments that are roughly equal to a transit time of particles through a focus of a laser beam. The segments are connected to a frequency domain through the use of an FFT algorithm to produce frequency domain data segments. Signal-to-noise ratio is enhanced through signal processing techniques using the segments to produce a final enhanced signal spectrum.
Systems and methods for measuring velocity in fluid are disclosed. In one aspect, a method (900) comprises transmitting a first set of signals of a bandwidth broader than the measuring system, receiving echoes from the first set of signals, obtaining a first velocity estimate based on the echoes, transmitting a second set of signals of a bandwidth narrower than the measuring system, receiving echoes from the second set of signals, obtaining velocity estimates based on the echoes from the second set of signals, selecting one of the velocity estimates based on the first velocity estimate. In another aspect, a method (280) comprises removing substantially a bias related to a first velocity from raw velocity estimates. In another aspect, a method (1900) comprises obtaining a velocity estimate for each of a set of transmitted pings, calculating a velocity based on the sum of the velocity estimates.
G01P 5/24 - Mesure de la vitesse des fluides, p.ex. d'un courant atmosphérique; Mesure de la vitesse de corps, p.ex. navires, aéronefs, par rapport à des fluides en mesurant l'influence directe du courant de fluide sur les propriétés d'une onde acoustique de détection
G01S 15/58 - Systèmes de détermination de la trajectoire ou de la vitesse; Systèmes de détermination du sens d'un mouvement
G01S 15/60 - Systèmes de détermination de la trajectoire ou de la vitesse; Systèmes de détermination du sens d'un mouvement dans lesquels l'émetteur et le récepteur sont montés sur l'objet mobile, p.ex. pour déterminer la vitesse par rapport au sol, l'angle de dérive, le trajet au sol
G01S 15/89 - Systèmes sonar, spécialement adaptés à des applications spécifiques pour la cartographie ou la représentation
13.
SYSTEM AND METHOD FOR ACOUSTIC DOPPLER VELOCITY PROCESSING WITH A PHASED ARRAY TRANSDUCER
Systems and methods for measuring velocity in fluid are disclosed. In one aspect, a method (900) comprises transmitting a first set of signals of a bandwidth broader than the measuring system, receiving echoes from the first set of signals, obtaining a first velocity estimate based on the echoes, transmitting a second set of signals of a bandwidth narrower than the measuring system, receiving echoes from the second set of signals, obtaining velocity estimates based on the echoes from the second set of signals, selecting one of the velocity estimates based on the first velocity estimate. In another aspect, a method (280) comprises removing substantially a bias related to a first velocity from raw velocity estimates. In another aspect, a method (1900) comprises obtaining a velocity estimate for each of a set of transmitted pings, calculating a velocity based on the sum of the velocity estimates.