Johns Hopkins University

Ronald W Mitnick

David A Kitchin

Juan I Arvelo, Jr

Charles W Kerechanin, Ii

Charles B Cooperman

A hydrophone unit comprising a resilient central wire; a conductive wire coiled around the resilient central wire, said conductive wire being coated with a piezo material for generating an electrical signal in response to the presence of an acoustic vibration, wherein the resilient central wire is fabricated from spring steel, the conductive wire is a copper wire, the piezo material includes polyvinylidene difluoride; a layer of conductive material deposited on the piezo material-coated conductive wire, wherein the layer of conductive material comprises a silver ink; and a jacket of polyurethane.

Hydrophone unit

A hydrophone deployment system including a hydrophone assembly, a container for enclosing the hydrophone assembly body in a coiled configuration, means for ejecting the hydrophone assembly from the container, a signal processing module for processing the electrical signals from the hydrophone units, and a transmitter module for converting said processed electrical signals and transmitting said converted signals to a remote receiver.

Vertical line hydrophone array

A hydrophone assembly includes at least four hydrophone units for converting an acoustic signal to an electrical signal, the hydrophone units being in a parallel, cylindrically symmetric spaced spatial relationship with each other, and at least one spacer element to maintain the hydrophone units fixed in the spatial relationship to each other, wherein the hydrophone units and spacer element are embedded in an encapsulant to form an elongated, flexible body.

A hydrophone array includes an inflatable shaped housing enclosing an interior space and formable between a collapsed configuration and an expanded configuration, a framework of compliant material disposed within the interior of the inflatable housing, and a plurality of hydrophones attached to the compliant material at respective positions, wherein said hydrophones are arranged in a predetermined geometric array when the shaped housing is in the expanded configuration. Also provided herein is a system and method for deploying the hydrophone array.

Water inflatable volumetric hydrophone array

A sonar system for detecting underwater acoustic signals includes a plurality of hydrophone units capable of converting acoustic impulses to electrical signals, the hydrophone units being substantially vertically oriented when deployed in a body of water, and the hydrophone units occupying at least some of the positions of an M&#xd7;N horizontal array. Two-dimensional Chebyshev mathematical weighting is applied to the electrical signals from the individual hydrophone units such that each individual signal from each hydrophone unit is assigned a respective weighting number and a numerical value is assigned to each individual signal corresponding to the strength of the electrical signal as adjusted by the respective weighting number.

Volumetric passive sonobuoy array of polyvinylidene fluoride (PVDF) wires

An expandable platform for deploying sensors in a medium includes a housing and a structural member disposed inside the housing. A releasable restraint is connected to the structural member. Multiple arms are connected to the structural member. Each arm includes a material memory component that has a natural state, corresponding to a minimum energy state, in an extended configuration. The material memory component is energized by compacting the material memory component so that the arm fits within the housing. The material memory component is restrained in an energized state by the restraint, and naturally transforms toward the extended configurations under its own force when the restraint is released. A flexible cable external to the arms is connected to two or more arms, each at a tip portion of the arm. The tip portion is farthest from the structural member when the material memory component is in the extended configuration. Multiple sensors are connected to the cable.

Growing community of inventors

Baltimore, MD, United States of America

Ronald W Mitnick