Abstract: An apparatus for providing thrust adjustment on an underwater vehicle with a propeller shroud is disclosed. A portion of the vehicles body is provided with a compliant surface such that expansion and contraction of the compliant surface affects the flow of water through a channel formed by the vehicle body and the propeller shroud, resulting in variable thrust on the vehicle.

Abstract: The invention as disclosed is of a buoyant cable antenna for use with underwater vehicles having improved bandwidth through the use of discrete distributed loading along the antenna. The buoyant cable antenna is designed with an antenna wire that is divided into N equal length segments of length d/2. A capacitor is coupled between every other segment such that capacitors are separated by a distance d. A shunt inductor is coupled to the antenna wire between the adjoining segments not separated by a capacitor such that the shunt inductors are separated by a distance d. This antenna design provides a substantially improved impedance bandwidth over existing prior art antennas at high frequency without increasing the physical profile of the antenna and without the use of active circuit elements.

Abstract: A system is provided to control maneuvering flapping foils of an underwater vehicle. An oscillator generates periodic signals in which effects of external disturbances are minimized or amplified as required; the periodic signal can be either sinusoidal or can depart significantly from a sinusoid; the amplitude and frequency are varied by changing the oscillator parameters and the phase between the signals are varied by changing the parameters. The oscillator restores the parameters after a disturbance. Since the oscillator functions without external sensors, the oscillator serves as an inner-loop controller with a centralized control. An open loop control architecture for the controller, results in a motion where the vehicle maneuvers execute as force and moment commands. The non-linear, auto-catalytic oscillator can be realized using a variety of second-order differential equations.

Abstract: The invention as disclosed is a method to identify and monitor/track ships as they traverse waterways. The earth's surface is partitioned into geospatial regions with attributes of each region being stored. A priority is assigned to each partitioned region. A variety of data sources are used to collect data about ships in the geospatial regions. The data is merged and presented in geospatial or tabular formats on a graphical user interface, where the data itself, the data accuracy, and the age of the data can be visually determined graphically and chromatically from the display.

Abstract: A system and method of use are provided for introducing tangential control fluid flows along the surface of an aerodynamic member. The fluid flows are directed toward a coanda surface disposed at the trailing edge of the aerodynamic member. At least two injection slots are provided on opposite sides of the aerodynamic member to produce opposing forces. Control of the flow of fluid from each slot determines the net effect of these opposing forces. Smart material actuators are used to control the flow of fluid from each slot by varying the size of each slot.

Abstract: An extrusion apparatus is taught that employs a die adapter that is partially submerged in a heat transfer bath on a horizontal plane such that there is no air gap between the die extrusion aperture and the heat transfer bath. A porous dam is positioned between the die and the heat transfer bath. A heat insulating plate is positioned between the porous dam and the die to prevent the heat transfer medium from flowing onto the die. The heat insulating plate also prevents excessive cooling of the die tip thereby allowing the necessary precise thermal control over the extrudate skin formation to prevent melt fracture and form a low density extrudate with a smooth solid skin and inner foamed core.

Abstract: An accelerometer is provided for a fiber optic laser. Strain applied to the fiber optic laser results in an emission wavelength shift. The fiber optic laser is joined to a transducer and extends laterally across said transducer. Acceleration of the transducer in a predefined direction causes strain in said fiber optic laser. The transducer can have many possible designs. There is further provided a system for sensing acceleration which includes a pumping laser and a distributor joined to the fiber optic laser. Return signals from the fiber optic laser are provided to an interferometer and analysis circuitry. In the absence of a transducer, the system can operate as a strain sensor.

Abstract: A combined antenna transmitter joined for transmitting a message signal includes a switching signal source modulated by the message signal. The switching signal is provided to a transistor at an operating frequency. The transistor switches a high voltage input through the transistor, a choke inductor and a boost inductor. A bypass capacitor is provided between the inductors for shielding the high voltage input. An antenna is connected between the boost inductor and the transistor for transmitting a radio frequency signal at the operating frequency. There is thus provided a compact, efficient transmitter and antenna assembly for transmitting modulated message signals.

Abstract: A method for utilizing a matched field-processing algorithm employing a number of sensors wherein the sensor output is the measured acoustic data as the first input and is translated to a frequency by applying a Fourier transform to a set of time samples as a data vector output. A replica vector is the second data input as a predicted quantity which is computed by an acoustic model with an assumed acoustic location. The output is an ambiguity surface ranging between zero and one with the highest values indicating the likely position of an acoustic location. The matched field response is generalized by averaging the response over multiple frequencies. A response for an array may be computed by forming beams and then combining them by multiplying each by an eigenray factor before summing. The computation of the response may be further defined by voxel interpolation.

Abstract: A towed array is provided with hot-film sensors and anemometer circuitry to calculate the angle of inclination of the towed array in real time during deployment of the towed array in a sea water environment. The hot-film sensors are arranged in pairs along the length of the towed array to increase the sensitivity of the inclination angle determinations and are located flush with an exterior surface of the towed array to minimize interference with the operation of the towed array. The pairs of hot-film sensors determine the local sheer stresses on the towed array, and these measurements are converted to inclination angles using an empirically derived look-up table.

Abstract: Disclosed is a launch system of an affixed lower section of launch tubing and an upper section of launch tubing configured to telescope vertically from a stowed position within the hull of a submarine to a position just above the ocean surface for a launch operation of a projectile, with the upper section returning to a stowed position after the launch operation. The launch system is capable of launching a projectile to engage air contacts by the discharge of high pressure fluid air, through the length of the upper and lower sections to impact the projectile for launch. The launch system includes surveillance, command and control elements as well as operational connection to additional projectile stowage and a supply of high pressure fluid. The projectile in use with the launch system can support surveillance and communications operations.

Abstract: A battery monitoring device for a battery having cells grouped in modules. The device includes a monitoring circuit for each module which monitors the voltage in each cell and the overall module voltage. The monitoring circuits can also detect module temperatures. The monitoring circuits are networked to a control computer. The device can be used with a power supply and relays for each module to interrupt charging when a fault condition is detected by the monitoring circuits. Other features of the device allow equalization of cells having excessive voltages.

Abstract: An interactive system is provided to help an operator locate the source of a data fault in an Asynchronous Transfer Mode (ATM) network. A database stores information related to data types and subsystems used by the ATM network. A processor coupled to the database uses the information stored therein to formulate a series of queries related to a selected one of the subsystems using the data type experiencing a data fault. The series of queries have a hierarchal order that sequentially inquire about operational status of the various subsystems having a relationship with the data type experiencing the data fault. A graphical user interface (GUI) coupled to the processor displays each query in accordance with the hierarchal order thereof. The GUI simultaneously displays identification of the various subsystems having a relationship with the data type experiencing the data fault.

Abstract: A visual-acoustic device is provided that contains an acoustic detector to produce sound waves in communication with a moiré pattern generator that produces moiré patterns corresponding to the sound waves. The device includes a rigid plate having a first repetitive pattern and a flexible plate spaced from the rigid, plate and having a second repetitive pattern corresponding to the first repetitive pattern. The sound waves induce movement of the flexible plate such that the second repetitive pattern moves with respect to the first repetitive pattern to produce the moiré pattern. The visual-acoustic device can be arranged as a visual-acoustic stethoscope.

Abstract: A polymer coating applied to a load bearing or contact surface of objects such as skis and snowboards is provided. The polymer coating is a drag reducing, water soluble long chain polymer such as polyethylene oxide. The polymer coating is applied to the contact surface of the object and dissolves into the thin layer of water that forms between the contact surface and a water-containing surface over which the object is passed. The polymer readily dissolves in the thin water layer, decreasing the friction between the contact surface of the ski or snowboard and the surface of the snow or ice.

Abstract: A control system for a supercavitating vehicle includes a set of winglets for rapid maneuverability and a segmented ring wing for fine stabilization control. The winglets and ring wing extend from an aft portion of the vehicle. The winglets are supported by a strut attached to the vehicle. The angle of attack of each winglet into the water adjacent the cavity is controlled by a winglet actuator. The winglet assembly may be extended into the water or retracted to be completely within the cavity by means of a spring-loaded actuated mount. The segmented ring wing is controlled by a ring actuator. The ring actuator may be used to control the angle of attack of the ring wing. Alternately, or in combination, the flow over the ring wing may be neutralized by using the cavitator of the vehicle to globally enlarge the cavity and thus limit the flow.

Abstract: A target for a test range includes an impact plate having at least three strain sensors positioned on the plate. The sensors are connected to a data acquisition board for receiving a signal from each sensor upon impact of a projectile on the plate. The data acquisition board is joined to a processor for calculating impact location and energy. Optionally multiple sensors can be provided having different orientations for accounting for different strain components in the plate.

Abstract: A driver circuit is provided for enabling a transistor collector-emitter path to be used as a broadband periodic switch. The broadband driver circuit controls the magnitude of the transistor base-emitter current in order to enable a CLOSED switch state and to simultaneously control the magnitude of the transistor base-emitter reverse-bias voltage in order to enable the OPEN-switch state. The precise control of these parameters minimizes base-charge storage and prevents reverse-breakdown failure.

Abstract: A marine acoustic sensor assembly includes an acoustic panel having a forward surface and an after surface, a laser scanner oriented so as to project a laser beam onto the acoustic panel after surface, and a sensor oriented so as to receive reflections of the laser beam off the acoustic panel and to transmit data from which a position of a sound generating source can be determined, wherein the acoustic panel is provided with an absorber layer extending over the after surface thereof, and the absorber layer is provided with holes extending therethrough, the holes being of a size sufficient to permit passage of the laser beams to the acoustic panel after surface and the reflections to pass to the sensor, whereby to minimize reflections and noise originating from aft of the after surface, while permitting sound incoming from forward of the acoustic panel to be measured.

Abstract: An accelerometer is provided including a strain sensor with a substantially linear configuration. The strain sensor is mounted on a transducer such that the strain sensor extends laterally across the transducer. The transducer has a base and a plurality of flaps joined at a first end to the base and supporting the strain sensor at a second end. The flaps translate acceleration in a predefined direction to strain in the strain sensor. Further embodiments have flaps defining an interrupted surface with greater height at the center and flaps that have features for enhancing the strain caused by acceleration.