Abstract: A method for manufacturing an electrolytic tilt sensor comprises: a) forming sensing electrodes on a generally planar surface of a dielectric substrate; b) forming a reference electrode on the surface; c) mounting a housing to the substrate so that the sensing electrodes and the reference electrode are contiguous to a volume defined between the housing and the substrate; d) forming a fluid tight seal between the housing and the substrate; e) injecting an electrolytic fluid into the volume; f) sealing the electrolytic fluid in the volume; and g) forming an electrical circuit on the substrate for generating an output signal representing the angle of the dielectric substrate with respect to a gravitational field, wherein the electrical circuit includes an oscillator mounted on the surface.

Abstract: The invention provides an automatic gain control system that is implemented by digital hardware. The digital hardware determines the range of a set of digital data values, and then examines each digital data value in a sequence. An index counter increments a sample count index i each time a new digital data value is examined and determines the absolute value of the ith digital data value. The digital hardware also counts both the number j of digital data values that exceed a high percentage value of the range, and the number k of digital data values that are less than a low percentage value of the range as the digital hardware runs through the sequence. If the digital hardware determines that a digital data value is greater than the high percentage value, the ratio j/i exceeds a first threshold value, and the gain level is not set to the lowest gain level, then the gain is decreased.

Abstract: A method for manufacturing an electrolytic tilt sensor comprises the steps of: a) forming first and second sensing electrodes on a generally planar surface of a dielectric substrate; b) forming a reference electrode on the generally planar surface; c) mounting a housing to the dielectric substrate so that the first and second sensing electrodes and the reference electrode are contiguous to a volume defined between the housing and the dielectric substrate; d) forming a fluid tight seal between the housing and the dielectric substrate; e) injecting an electrolytic fluid into the volume; f) sealing the electrolytic fluid in the volume; and g) forming an electrical circuit on the dielectric substrate for generating an output signal representing an angular position of the dielectric substrate with respect to a gravitational field.

Abstract: A snowmobile having a liquid-cooled engine with an improved cooling system is disclosed. The snowmobile has a chassis with a drive tunnel. Horizontal footrests extend laterally from opposite sides of the chassis. The snowmobile also has left and right elongate side coolers that dissipate heat generated by the engine. The side coolers have a hollow interior that is in fluid communication with liquid coolant passages in the engine. Each cooler extends longitudinally and is mounted at an outer edge of a respective footrest to form a footwell. The snowmobile has a pump that circulates coolant throughout the coolant circuit formed by the side coolers and the internal passages of the engine. The side coolers may also contain heat exchanging anti-skid studs that extend outward from the surface of each side cooler. The snowmobile may also contain front and rear heat exchangers connected within the coolant circuit and positioned at the front and rear ends of the tunnel, respectively.

Abstract: A system for determining the time between the receipt of two different sils, includes a voltage ramp generator which generates a time dependent voltage signal upon receipt of a timing pulse at a time T.sub.1, and provides the instantaneous value of the voltage signal when the voltage ramp generator receives an input signal having a predetermined threshold value at time T.sub.2. A data processor coupled to receive the voltage signal, generates the timing pulse, and determines a time difference .DELTA.T from the voltage signal, where .DELTA.T=T.sub.2 -T.sub.1.

Abstract: A buoyed sensor array communications system comprises multiple sensor syss electrically connected to a signal transmission line which are positioned at predetermined locations along the signal transmission line to form a linear sensor array. Each of the sensor systems generates a data signal in response to receiving an address signal. The system further includes; a processor system electrically connected to the signal transmission line for transmitting address signals to enable any one of the sensor systems at a time in a selectively accessed order and has a data storage memory for storing the data signal from each of the sensor systems as stored data. A radio frequency transmitting system is coupled to the data processor and transmits the stored data at a predetermined time. A negatively buoyant structure connected to the signal transmission line pulls the communications system to the bottom of a body of water upon deployment.

Abstract: An electronic circuit architecture time-division-multiplexes analog sensor ignals from a distributed sensor array onto a common transmission line in a digitally encoded format. The architecture synchronizes the multiplexing, sampling and encoding to ensure a proper settling of the analog data signals and is fabricated to be compact with low power consumption for a cost-effective implementation for a number of sensors.

Abstract: An air/sea temperature probe is disclosed which can be deployed from a moving ship to detect the temperature profile of the atmosphere and ocean beyond the thermal influence of a ship. The probe includes a temperature transducer which utilizes a bifilar wire that provides a very quick air temperature time constant. The transducer is mounted within a radiation shield having low thermal conductance to minimize thermal and solar radiation contamination and is coupled to a signal processing network. In operation, the probe is deployed from a ship and provides temperature telemetry via an electrical data link coupled between the signal processing network and a receiving transducer located onboard the ship.

Abstract: A system for minimizing the power requirement of a flowmeter intended for long-term unattended deployment in a current flowing through a body of conductive fluid. The system includes a pair of electrodes in contact with the fluid, and a permanent magnet which generates a magnetic field which is orthogonal to a line passing between the electrodes. An electromagnetic coil is also provided, and is selectively activated and deactivated to establish the orthogonal magnetic field at a first level during first time periods in a series of first time periods, and at a second level during second time periods in a series of second time periods. The ratio of the time duration of a first time period to a second time period is substantially less than one.

Abstract: An oceanographic flow sensor for use in component type electro-magnetic fmeters includes a pair of spaced electrodes and a conductive coil wound thereabout having a small enclosed area. A sensor construction is also disclosed having a plurality of mutually perpendicular coils. A preferred embodiment uses a conductive coil wound along a bent winding axis such that mutually perpendicular sensing electrodes may use the electromagnetically generated field from a single winding.

Abstract: An underwater sensing system has a trunk cable that transmits a plurality clock signals from its first end to its second end. A plurality of signal handling nodes are installed successively along the trunk cable in a spaced apart relationship. Each of a plurality of linear sensor arrays extend from one signal handling node. Each sensor in the sensor arrays receives the clock signals and generates a data output signal in response thereto at specifically ordered time sampled intervals based on a count of the clock signals. The data output signals are transmitted to the one signal handling node associated with the sensor array. At each of the signal handling nodes, a multiplexer interleaves the data output signals received from its sensor array in a continual throughput, time-division multiplexed fashion with concatenated data output signals received from the next successive signal handling node located further from the first end of the trunk cable.

Abstract: An impervious cable connected electrical component assembly is provided wh includes an electrical component which has a conductive wire extending therefrom. An impervious container is provided which has an open top and a closed bottom. The electrical component is located within the container with its conductive wire extending out of and beyond the container's top. A cable is provided which has a conductive wire within an impervious sheath. A lengthwise portion of this wire is exposed. The conductive wire extending from the top of the container and the exposed conductive wire portion of the cable are electrically joined at a junction outside the container. An impervious sleeve is bonded to the cable sheath so as to hermetically seal the wire junction along the cable. The open top of the container and the sleeve are bonded to hermetically seal the electrical component.

Abstract: A buoyed sensor array communications system comprises multiple sensor syss electrically connected to a signal transmission line which are positioned at predetermined locations along the signal transmission line to form a linear sensor array. Each of the sensor systems generates a data signal in response to receiving an address signal. The system further includes; a processor system electrically connected to the signal transmission line for transmitting address signals to enable any one of the sensor systems at a time in a selectively accessed order and has a data storage memory for storing the data signal from each of the sensor systems as stored data. A radio frequency transmitting system is coupled to the data processor and transmits the stored data at a predetermined time. A negatively buoyant structure connected to the signal transmission line pulls the communications system to the bottom of a body of water upon deployment.