Abstract: An acoustic levitator device for suspending a specimen object under the influence of gravity without contact with a solid surface comprising in combination gas levitation means for directing a concentrated flow of gas along an axis upwardly against the object to provide a force to lift a majority weight of the object, and acoustic levitation means for exerting an acoustic positioning force on said object to restrain movement away from said axis and to hold said object in a given position.

Abstract: A seismic pulse generator comprises a body 1 having an internal gas-pressurizable first chamber 2 adjoining a second chamber 6 for containing a fluid. A flap valve member 21 is rotatable about a pivot axis for closing a bore 24 communicating with the first chamber. A latch 22 releasably retains the flap valve member in the closed position and a gas operated piston 13 slidably moves within an associated cylinder 12. When the first chamber 2 is pressurized with gas and the flap valve member 21 is released from its closed position to uncover the bore 24, the piston 13 moves to cause communication between the chambers 2,6 and generation of a shock wave in the second chamber. The second chamber has outlet means 7 to permit a pulse of energy to be transmitted from the second chamber in response to the shock wave generated in the second chamber.

Abstract: In a device for the suspension of a sonar acoustic base within its protection dome, two connection rods are used. These two connection rods are hinged, by one side, on the hull of the ship and, on the other side, on the acoustic base. These connection rods form a triangular system which, during the motions of the base, dictates a rotation of this base about an instantaneous center of rotation R located above the center of gravity G of the base. In this way, when the base touches the internal surface of the dome, the impact occurs as a surface-to-surface impact and not as a corner-to-surface impact. This limits the damage caused by the impacts, thus making it possible to obtain, simultaneously, a very free suspension of the acoustic base and efficient protection of the sonar dome.

Abstract: A supersonic inlet flow duct (10) is provided with a pivoting bleed stability door (34) and biasing spring (42). The door (34) opens under the influence of increased static fluid pressure behind a shock front (24) which is displaced forwardly by a downstream pressure perturbation. The opened door (34) diverts portions (31, 44) of the inlet duct flow stabilizing the shock front (24a) and downstream shock train (25) within the duct (10) until the perturbation subsides.

Abstract: A hand-held underwater distance measurement device has a first end having a waterproof housing which houses a digital display and a suitable electronics package, a second end housing a transceiver, a middle section having a pair of rectangular telescoping rigid tubes with a spring lock clip for fixing the relative locations of the tubes at two or more locations via the provision of holes in each of the tubes, and a flexible conductor for coupling the transceiver and the electronics package. The upper of the pair of telescoping rigid tubes is mechanically coupled to the waterproof housing, while the lower of the pair is coupled to the transceiver, which in one embodiment is rotatable relative to the lower tube to permit horizontal scanning. In using the device, the transceiver is immersed at least six inches below the water surface while grasping the device by a hand grip located just below the electronics package housing.

Abstract: A device for separating a space for cargo in a vehicle, for example in an aircraft cabin or compartment, is constructed for keeping pieces of cargo, for example baggage, in place and to even intercept cargo pieces that may have gotten loose. Such a structure is secured to the vehicle, e.g. an aircraft body, by ceiling brackets and floor mountings. The wall itself is a multilayer structure with different layers provided for different purposes. At least one layer or strut structure is arranged for taking up impact energy effective in a direction in which impact forces are effective, primarily in the travel direction of the vehicle.

Abstract: A hydrophone with crossed pairs of geophones is provided with a strong light weight housing allowing use at several thousand feet deep in the ocean while still maintaining good sensitivity. The cruciform housing has a cylindrical portion conforming to each of the four geophones so that each cylindrical wall has small diameter and requires small thickness. The cylindrical portions are joined to a central body to complete the housing.

Abstract: A digital electronics unit (81), missile, and missile system for a tube-launched missile. The invention utilizes a positional status mechanism (10) to structure signals from the on-board gyro system (80) and a directional mechanism (11) to separate signals from an operator. These signals are handled by a digital micro-controller (12) to create the proper control signals for manipulation of the missile in the missile system.

Abstract: In a weapon system 10 incorporating a target position sensor (14), an information system (16), a power source (24), a launcher (20), and an airborne vehicle (18), a launcher control system (12) incorporates a communications interface (26) for coupling the information system (16) and the target position sensor (14) to a launcher (20) and an airborne vehicle (18). The communications interface (26) receives target position information and launch and control orders and provides launcher and airborne vehicle status. A airborne vehicle interface (28) couples the launcher (20) and the airborne vehicle (18) to the information system (16) and a power source (22). A transmitter (30) communicates updated target position information to the airborne vehicle after launch. A power control means (32) converts and regulates power from different power sources (22) to be used by the launcher control system (12).

Abstract: An apparatus for forcing a member or device, such as a sample tube or seismic or geological instrument, through a material such as soil along a selected line of action. The apparatus includes a derrick with first and second plates mounted thereto, the second plate having a locking dog extending through a hole therein for engaging a collar set in material, and the first plate being provided with a hydraulic cylinder or other device for forcing the member through the material. The first plate is also provided with an extruder head for releasably mounting the sample-containing sample tube thereto, and the hydraulic cylinder is provided with a plunger releasably mounted to the ram thereof, for extruding the sample from the sample tube.The collar positively engages the material to provide an apparatus for transmitting the reactive forces resulting from forcing the member through the material to the material.

Abstract: A mechanical oscillator driven by drilling fluid flow pumped down a drill string bore is combined with sensors and controls to produce a downhole drilling fluid pressure pulse generator for use in drill strings for Measurement While Drilling (MWD) pipe bore telemetry.A fluid flow responsive valve designed to be put in continual motion by fluid flow is associated with a motion stop lock so that, on release, a discrete digital fluid pressure change is generated. A downhole instrument package controls the lock release in a timed sequence, so that a series of pressure changes represent information to be decoded at the earth surface to determine downhole parameters sensed by the instrument package.The active elements of the downhole system may be installed in the drill string or lowered as a shuttle package down the drill bore.The fluid pressure pulse generating apparatus can be classified as a fluid flow excited oscillator or an auto-cycling pulse generator.

Abstract: The present invention relates to a hydrophone specifically designed for use in high pressure shock wave fields, comprising a thin piezoelectric polymer film secured to a rigid hoop structure, having a centrally located active element and two conducting leads extending from the active element on each side of the film. Under the action of high pressure shock waves, the conductive material which makes up the active area electrode and the conductive leads is slowly removed, altering the hydrophone's sensitivity and eventually rendering it unusable. The present invention provides an improved design for a hydrophone which monitors the loss of electrode and lead integrity due to shock wave action so that the hydrophone may be replaced before it produces invalid readings. The leads on each side of the centrally located active element are electrically switched to measure the resistance between the leads and the central portion.

Abstract: The method and the device are designed to cause the signal of each hydrophone of an antenna to be rid of the component due to the vibrations of a wall close to which the antenna is placed. To this end, a correction signal is deducted from the signal of the hydrophone. This connection signal takes account of the vibrations of the wall measured by sensors placed on the wall, in the vicinity of the antenna. The study of the circuit which enables this correction signal to be given is done by resolving the vibration of the wall into its dominant modes of deformation.

Abstract: The sonar transducer is protected from explosion shock by a variable impedance device, such as a metal oxide varistor, connected in parallel with the energy conversion component. The varistor normally has a very high electrical impedance, but becomes conductive upon application of the very high voltage output of the energy conversion component as a result of a rapid increase in mechanical energy, such as would accompany an underwater explosion in the vicinity of the transducer, to limit both voltage and current to a safe level so that the transducer can thereafter operate within acceptable parameters.

Abstract: A system in which a surface tension device is connected at the outlet of the propellant tanks, said surface tension device having surface tension gas barrier means, the presence of gas bubbles at the inlet of said surface tension device is detected and a detect signal is produced, said detect signal indicating that the propellant tanks are empty. The detect signal then causes the spacecraft thrusters to be fed from an auxiliary propellant tank. The latter can be implemented inside a main propellant tank.

Abstract: A target detection method for a flying body provided with a search head, with the flying body rotating during its descending flight and scanning the area for possible targets, and in which the geometric dimensions of possible targets are determined in the scanning direction (Y direction) and in a direction perpendicular to the scanning direction (X direction) and are compared with corresponding stored values to determine the presence of a target. To avoid distortions of the scanned target in the Y direction, at least the angular velocity .omega. of the flying body, and preferably also the angle .phi. between the axis of rotation and the symmetry axis of the flying body, is continuously determined during the scanning process and, image correction values are calculated from the determined values and used to correct the geometric dimensions of the possible target in the Y direction.

Abstract: A displacement amplifier interconnects a piezoelectric actuator with a displacement member and comprises respective bellows members of differential diameter defining first and second expansible chambers which are liquid filled and respond to linear displacement of a stack of piezoelectric disks to provide an amplified linear displacement to the displacement member. The transducer is particularly useful as a signal transmitting or receiving transducer for acoustic wave generation or measurement for wellbore logging tools.

Abstract: A sonar projector having a pair of opposed oscillating pistons driven by an electromagnetic assembly is rendered capable of operating at reduced resonant frequency by providing liquid mass loading for the pistons. The mass loading is achieved by utilizing a structure which constricts a body of liquid on one side of the piston. The constricted liquid may be sea water or liquid sealed within the body of the unit. In accordance with a further aspect of the invention, a seal assembly is provided for the moving pistons which not only provides a sealing function but which also acts to radially center the pistons and to provide an axially directed restoring force thereto during piston oscillation. The electromagnetic assembly, in accordance with still a further aspect of the invention, is formed with a permanent magnet structure arranged in a cylindrical configuration with the opposed pistons on opposite axial ends thereof to reduce magnetic leakage losses.

Abstract: The current invention is a multi-channel apparatus for inspecting and packaging loose ammunition cartridges into containers such as boxes or trays. The operation of the apparatus is largely automatic so that a single operator can inspect for defects and load into containers up to 28,000 rounds of both rim or rimless cartridges as well as various sizes of ammunition per hour with little manual labor involved.The apparatus includes a frame having an upstanding portion and a horizontal table portion. A reservoir for holding the bulk ammunition in loose form is mounted on the top of the upstanding portion of the frame. The apparatus also includes a mechanism for sorting and feeding the ammunition into feed tubes which feeds the ammunition down onto a conveyor table. The conveyor table moves the ammunition in an ordered fashion through an inspection area to an orienting device where the cartridges are oriented nose downward and directed into a loading mechanism.

Abstract: An acoustic transducer with an improved electret assembly mounting for providing spacings between the fixed and movable electrodes, and having as one feature the lowering of the undesired capacitance therebetween.