Abstract: A watercraft mounting system that embodies a moving mounting platform and a protective hull cavity which provides protection, prevents damage and improves storage of data collection systems.

Abstract: A pneumatic sounder and a control system thereof are disclosed. The pneumatic sounder comprises double magnets and a double-moving coil assembly. The double magnets comprise a first magnet and a second magnet, and the double-moving coil assembly comprises a first moving coil and a second moving coil. The first moving coil is disposed in a magnetic field of the first magnet, and the second moving coil is disposed in a magnetic field of the second magnet. The first moving coil and the second moving coil are connected to an electrical signal control system respectively, and a control system for the pneumatic sounder is also provided. The sounder greatly enhances adjustment efficiency of a cutting seam, reduces energy consumption for driving moving coils, guarantees services lives of the moving coils, and increases reliability of a system.

Abstract: A method for monitoring the condition of apparatus located at an underwater facility that includes sensing at least one parameter associated with the apparatus, providing a model of expected behavior of said at least one parameter, comparing said sensed parameter with said model, and assessing the condition of the apparatus based upon said comparison.

Abstract: A system of signal emitting modules is disclosed. The modules emit light or other signals to warn oncoming traffic that a road or other pathway has changed or is traversing a tortuous pathway. The modules are interconnected in a sequence so that they flash on and off in a pattern that leads the driver or observer along a path with less confusion than with randomly flashing or steady lights or reflectors. The modules are self-powered and can be arrayed first and programmed following deployment. The programming can be done with “mesh” technology, an external controller, or by dialing a specific number in each of a plurality of distributed controllers. The modules can improve highway safety by reducing driver confusion. The modules are arrayed to prevent a driver from seeing them from an oncoming direction. The driver coming from the opposite direction will have his or her own guiding system.

Abstract: A signalling device (10) adapted to make a percussive sound, for example, under water. The signalling device (10) may be attached to a pressurized fluid source, such as a diver's compressed air supply, the device (10) including: a housing (12) having a passageway (22), at least in part, for communication with the fluid source; a valve member (34) located in the passageway (22) and movable between a closed position in which it substantially blocks the passageway (22), and an open position in which fluid may flow through the passageway (22); biasing means (42), such as a spring, biasing the valve member (34) towards the closed position, wherein the valve member (34) reciprocates between the open and closed positions when a pressure difference above a set value exists on either of the valve member (34) to produce a perscussive sound.

Abstract: A simple mechanical device is provided which generates acoustic signals at ne or more specified depths. The device consists of a spring loaded piston placed in a wall of a housing, the spring loading biasing the piston away from the housing. The piston is subjected to a pressure differential between the exterior and interior of the housing such that the piston moves against the spring force and into the housing as the pressure differential, corresponding to a depth of the housing beneath a water surface, increases. As the piston moves further into the housing, it contacts a series of latches, each latch being used to detain spring loaded striker. The latches are spaced along the travel path of the piston such that each striker is associated with a specific piston movement, or depth. When the piston contacts a latch, the striker is released and strikes against a ledge within the housing, creating one of the acoustic signals.

Abstract: A simple, mechanical device is provided which produces an acoustic signal a specified depth. The device consists of a shear plug in an exterior wall of the device housing which prevents the movement of a spring biased piston. The plug is subjected to increasing differential pressure between the exterior and interior of the housing as the depth of the device beneath the water surface increases. At a known pressure differential, corresponding to a specified depth, the shear plug fails, allowing for the actuation of the piston. The spring biased piston strikes against a ledge in the device, creating the acoustic signal.

Abstract: An amphibious audible alarm device for a diver to use with an air tank in the water or above water surface in the event of incident or emergency to get other people's attention. The device includes a valve member connecting with the air tank for controlling compressed air flow, a noise making mechanism includes a piston reciprocally movable within a cylinder because of compressed air and an impact member to receive the impact of the piston to produce audible sound, and a body to house the valve member and the noise making mechanism. The device can work equally well in the water or in the atmosphere. It is compact size, simply structured, easy to carry and use.

Abstract: An underwater communication device that is simple in design, is simple to operate, is powered solely by a user's wrist action, has only one moving part, is maintenance free, can offer multiple modes of operation, can be made resistant to accidental sound generation, can be made neutrally buoyant, offers a wide margin of safety and reliability, and enables underwater communication up to 100 feet between scuba divers. The underwater communication device including a striker rod, a tubular housing and a support and guide member. The support and guide member supporting the rod in the housing. Communicating underwater with the underwater communication device by the steps of grasping the device approximately along its midpoint, and rapidly rocking or shaking the device from side to side or end to end, causing the endpoints of the striker rod to strike an inner surface of the housing, creating a sound that is readily propagated through the water.

Abstract: An underwater transducer assembly (T or P) is mounted on an elongated cylindrical piston (32 or 90) received in a pneumatic cylinder (31 or 91). One or more springs (41 or 92) normally bias the piston (32 or 90) inward into the cylinder (31 or 91) to retract the transducer assembly (T or P) into a sea chest (S'). Air under pressure introduced into the cylinder (31 or 91) is effective to overcome the force of the springs (31 or 91) and project the transducer assembly (T or P) to a position operative for scanning. Force applied to the transducer assembly (T or P) tends to move the piston (32 or 90) inward into the cylinder and thereby increase the pressure of the system. The transducer assembly (T or P) is retracted automatically if the pressure exceeds a predetermined pressure. A separate mechanical sensor is mounted adjacent to the sea chest S' to detect the presence of obstacles or debris and automatically actuate retraction of the transducer assembly (T or P).

Abstract: An alarm apparatus, for use with conventional diving equipment or other self-contained breathing apparatus, having a body portion (34) and a noisemaker portion (32). The body portion (34) includes a first opening (42) therethrough communicating with a connection for a first hose (14) from an air tank. The body portion (34) includes another opening (50) in fluid communication with the first opening in which is positioned a guide element (68). A movable stem element (75) is positioned within said guide element (68). A bore (64) extends between the second opening (50) and the noisemaker portion (32) in which a horn bell (84) supported by a diaphragm (94) are positioned. A button (80) is connected to the stem element (75) and is biased in one position by a spring (82). Actuation of the button (80) results in fluid communication between the first opening (42) in the body portion (34) and the noisemaker portion (32), further resulting in an audible alarm.

Abstract: An audible signalling system is provided for us by divers or the like to provide a relatively loud audible signal which can be used to indicate diver position, to signal distress, etc. The preferred system utilizes an air horn carried by the diver and adapted for connection to a pressurized air supply carried by the diver for breathing purposes. When the air horn is connected to the air supply, the horn can be operated to produce a loud audio signal of substantial range which can be heard relatively easily over ambient noise such as wind, water and/or boat noise. In one form, a sonic oscillator for use in underwater signalling is also included.

Abstract: An underwater transient sound generator for broadcasting optimum acoustical onic energy in sea water with an appropriate intensity and frequency spectrum to achieve passivation of acoustical mines. A high pressure bubble is released from a chamber while a resilient diaphragm is simultaneously vibrated, the diaphragm having at least one of its surfaces in contact with the sea water. The system provides an improved pneumatic-mechanical impact sound source that produces a controllable distribution of high power, broad band spectrum acoustical energy, to temporarily inactivate acoustical mines, while masking the noise of the ship as it passes the mine.

Abstract: A method and apparatus for pressure compensating an underwater housing by blowing up a balloon and sealing the balloon mouth around a conduit to pneumatically connect the balloon to the interior of the housing. The balloon is configured to change its appearance either structurally or via indicia to provide a variable indication as to what depth it will provide compensating air. The indication varies in response to the amount the balloon stretches to accommodate the air forced into the balloon as it is blown up.

Abstract: 1.

Abstract: 4. An underwater noise generator comprising a thick-walled hollow cylindrl housing, said housing having continuous inner and outer cylindrical surfaces and at least one hollow portion between said inner and outer surfaces; a spindle rotatably mounted within said housing along the longitudinal axis thereof, means for rotating said spindle, and a roller mounted on said spindle and driven thereby in rolling contact with said inner surface of said housing, said roller having a plurality of grooves cut in the exterior surface thereof, whereby sound is produced as said rollers roll on said cylindrical housing.

Abstract: An underwater noisemaking device that is self-driven for use in towed undater acoustic minesweeping or as a decoy countermeasure device. It comprises a cambered and slotted disc mounted in a frame so as to be free to rotate about a horizontal, transverse axis within its plane when being towed or is in a flow stream. The disc auto-rotates rapidly causing intermittent cavitation, resulting in the emission of loud "clapping" acoustic noise. It may be incorporated into other towed underwater acoustic minesweeping and decoy devices.

Abstract: 1. An apparatus for producing low frequency compressional waves under water hich comprises two circular plates spaced in opposed parallel relation, a plurality of reciprocating fluid motors arranged in parallel between said plates, an independent fluid pump hydraulically connected to each of said motors for driving the same, a by-pass valve for each motor adjustable to vary the length of the stroke of such motor, a prime mover coupled to drive all of the pumps in synchronism, whereby the motors connected thereto reciprocate in unison to move said plates toward and away from each other at a frequency corresponding to the speed of the prime mover, and means for adjusting all of the by-pass valves in assembly, whereby the amplitude of oscillation of said plates is correspondingly varied.

Abstract: 1. An acoustical source for minesweeping operations comprising a stator ing outer and inner surfaces which are surfaces of revolution and an open port connecting said outer and inner surfaces, an external rotor adapted to be rotated around said outer surface of said stator and having outer and inner surfaces which are surfaces of revolution with at least one open port of non-constant cross-section connecting said inner and outer surfaces, said port being substantially larger in cross-sectional area at said inner surface than its cross-sectional area at said outer surface and, said rotor having appreciably greater thickness between said inner and outer surfaces than said stator; and drive means for rotating said rotor at a predetermined speed.