Abstract: An apparatus for sensing and correcting force levels and vibrational frequencies in a cylindrical grinding machine which has active centers. The active centers have imbedded shear load sensors and imbedded actuators. The sensors provide real time grinding information and allow for a determination of undesirable force levels and vibrational frequencies. The actuators are a pair of piezoelectric stacks disposed on opposing sides of the center body in indentations. A voltage applied by a controller causes the piezoelectric stacks to expand and contract. The action of the piezoelectric stacks causes the tip of the center to laterally displace and apply a lateral force to the workpiece. An AC voltage waveform may be applied for force control. A DC voltage may be applied for displacement; for example, to rapidly remove the workpiece from the grinding wheel or to correct for misalignment between the workpiece and the wheel.

Abstract: A deep water tow system adapted for being towed by a tow cable behind a ship includes a buoyant tow vehicle for housing apparatus to be used underwater, a coupler for connecting the tow vehicle to the tow cable, and a weight in the form of a multi-link chain attached to the tow cable at a location some predetermined distance from the tow vehicle. The chain is of sufficient weight to pull the tow vehicle downwardly in water until the chain contacts the water floor. When pulled by a surface vessel, the chain is pulled over the water floor and the tow vehicle is maintained some fairly constant predetermined distance above the water floor.

Abstract: Method and apparatus for detecting the presence of liquid in a container includes an elongate rod (or other vibratory element) which extends into the container to contact liquid when a certain amount of liquid is present, a piezo-electric element coupled to the rod on the exterior of the container to cause the rod to vibrate in response to electrical signals and to produce electrical signals indicative of the amplitude of vibration of the rod, and circuitry for producing a utilization signal when the electrical signals produced by the piezo-electric element indicate that the amplitude and duration of vibrations of the rod are below some threshold level. Such vibrations fall below the threshold level when the rod contacts liquid in the tank and so production of the utilization signal is an indication that liquid in the container has reached a certain level.

Abstract: A sonar transducer especially adapted for use when subjected to high hydrostatic pressures and extreme mechanical and explosive shock. The sonar transducer includes a conventional casing, ruggedized to withstand high pressures and a hostile environment. The casing is closed on all sides but one. An array of piezoelectric ceramic stacks are suspended inside of the casing and sandwiched between a single front mass and individual rear masses. The single front mass is positioned closest to the open side of the casing. A flexible cover is sealed over the open side of the casing and pressurized oil is placed inside the housing. Appropriate channels are provided to enable the oil to freely flow throughout the interior of the unit, including flowing inside of and about the ceramic stacks. Electrical connections are made with the ceramic stacks to allow external voltages to electrically stress the stacks, and also to allow external sensing of the voltages generated when the stacks are mechanically stressed.

Abstract: A dry film processor includes a housing, a film supply canister disposed in the housing for holding film and supplying it to the other processing apparatus, a take-up canister also disposed in the housing for receiving and holding the film after it has been processed, storage apparatus for receiving film from the supply canister and for supplying the film to the take-up canister, a drive roller for moving the film from the supply canister to the storage apparatus at a speed determined by certain input speed signals, heater apparatus for heating the film to enable development thereof, drive belt apparatus responsive to control signals for moving the film to withdraw it from the storage apparatus and move it past the heater apparatus, and a control unit for supplying control signals to the drive belt apparatus.

Abstract: A graphic recording system for use with a multiple channel underwater sonar system. The recording system includes a plurality of memories, each for storing information received over a different channel of the sonar system. One or more channels may carry side scan sonar information, while another may carry sub-bottom sonar information, etc. The information from the channels is received and stored in the memories simultaneously. The recording system further includes a graphic line recorder which is responsive to the receipt of a sequence of signals for producing on chart paper a line trace representation of the signals. A control unit controls the storage of information in and retrieval of information from the memories and application of the information to the graphic line recorder in such a manner that the information may be applied to the recorder in various sequences and at various rates.

Abstract: A sonar/television system and method is disclosed whereby an underwater drill pipe may be guided to a re-entry guide base or assembly positioned on a sea floor. The system includes a scanner assembly having first and second elongated housings whose exterior dimensions enable insertion of the housings into the bore of the drill pipe. The upper end of the first housing is rotatably mounted to the lower end of the second housing. A television camera is disposed within the first housing and fixed to the second housing so that the camera remains fixed when the first housing is rotated, and a sonar transducer is mounted in the first housing to rotate therewith. Scenes viewed by the camera are reproduced on a screen of a television display apparatus in such a manner that, when the re-entry guide base is within view, markings on the screen indicate both the lateral positioning of the drill pipe relative to the guide base and also the altitude of the drill pipe above the guide base.