Abstract: Apparatus is provided for adapting an analog depth sounder for the calling out of the depth at regular time intervals. In one embodiment, a self-contained adapter module is mounted to the face of the depth sounder so as to cover the depth sounder display, with the module including a transparent plate carrying a detector array and with electronics and speaker carried at the center of the array. In this embodiment, the detectors are arranged in thin radially extending lines to permit accommodation to displays of different diameter. Alternatively, small detectors are arranged along a circle having a diameter which overlies at least a portion of the orbiting radiating element which radiates along a considerable length. This alternative array configuration also accommodates a range of display diameters. As a further alternative, to accommodate different diameter displays, the thin line detectors may be replaced with radially extending light pipes with detectors at their ends.

Abstract: A depthsounder for selectively measuring either bottom depth or the depth of any fish located beneath a vessel. When operating in a depth mode, the depthsounder automatically adjusts the gain of its receiver to minimize interference and provide a filtered display of bottom depth. When operating in a fish finding mode, the depthsounder likewise automatically adjusts the gain of its receiver to minimize interference in its detection of fish. In addition, the depthsounder suitably processes any return pulses to distinguish those produced by fish from those produced by other objects in the water. When fish are detected, the depthsounder provides a visual display of their depth and an aural alarm whose repetition rate is proportional to the number and size of the fish.

Abstract: An improved method and apparatus for measuring the length of an open pipe includes a sound transducer placed in spaced open air communication with the interior of the pipe at a selected end. A logic circuit is employed with the transducer for producing a square wave sound pulse that is directed at the pipe's selected end. An oscillator provides an ambient temperature modified count in accordance with the time required for the pulse to travel the length of the pipe and return. For compensating for error tending to be introduced because of the spacing of the impedance reflective surface at the far end of the pipe, a standoff device establishes such a distance between the transducer and the selected end of the pipe as to effect an adjustment in the duration of the oscillator count that corrects for the error.

Abstract: An ultrasonic, echo-ranging instrument for measuring the level of liquid in an open channel or tank. The instrument includes a transducer disposed at a fixed position directly above the liquid surface, the nature of the gaseous environment therebetween determining the velocity of ultrasonic energy propagated therethrough. The transducer is excited to emit periodic pulses which are intercepted by the liquid surface and by a reference point a fixed distance from the transducer to produce both reference and liquid echo pulses that are returned to the transducer and detected thereby. The respective transit times of the reference echo and the liquid echo pulses are determined, and the ratio between these transit times is computed to provide an output representing the level of liquid independent of changes in the gaseous environment. To ensure accurate readings, the reference echo and liquid echo pulses from the transducer are fed to a single automatic gain control circuit whose operation is time shared.

Abstract: A system for measuring the distance between two objects, for determining the center between two objects and for triangulating the height of a tall object. In measuring the distance between two objects, an initial count is started when a first ultrasonic pulse is transmitted. The initial count is stopped when that pulse is received. The second pulse is transmitted only after a delay interval where the delay interval begins at the start of the initial count and is substantially equal to the maximum range time of a transducer. The restarted count is stopped when the second pulse is received, and the resultant count is displayed as a number related to the total distance between the objects.

Abstract: Method and apparatus for determining the distance from a preselected point to a target. An electrostatic ultrasonic transducer in a special protective housing is used with a single-pulse, square-wave transmitter to compare a main signal with a calibration signal. A warning signal indicates when the number of signals actually received during each one hundred signals sent drops below a predetermined percentage. Noise is minimized by careful spacing and shaping of the calibration bar and by insulating foam in the housing.

Abstract: The invention is particularly useful for counting the passengers moving into and out of a common carrier vehicle such as a motor bus. Three ultrasonic ranging stations are provided to determine the presence and absence of passengers at three successive positions at the bus entrance. The three positions may correspond respectively to three steps through the entrance. Sequence logic circuitry is included for analyzing the sequence of detection of passengers at the three different ranging stations to establish a count of the number of passengers entering or leaving.

Abstract: A distance measurement system for measuring distance to an object by emitting light to the object and measuring the intensity of light reflected from the object.

Abstract: The method and arrangement contemplates transmitting externally triggered trigger pulses by means of a magnetostrictive line or conductor and such produces echo pulses. Displacement path and time oscillator pulses are counted by two counter groups, and there is computed from the counter state the velocity-corrected position of a measuring head. Consequently, with a higher measuring rate there can be appreciably increased the accuracy of the evaluation of the pulses delivered by the ultrasonic measuring system, there can be obtained further measuring data (velocity and acceleration) by means of the moving measuring head, and there is possible an absolute measurement. Additionally, the resolution of the measured displacement path or distance can be randomly selected by means of the frequency of the displacement path or distance oscillator.

Abstract: A system measures the (x, y) coordinates of a target, for example, a pointed finger on a flat surface such as a rectangular plate. A pair of ultrasonic transducers are placed on the plate so that one transducer is located at each of the two left corners of the plate or at each of the two top corners of the plate. The transducers transmit short ultrasonic pulses which are reflected as echos off the target and then received by the transducers. The time elapsed between the transmitting of each pulse and receiving its echo is converted into distances between the transducers and the target, which distances are then converted into the target's (x, y) coordinates.The system is designed to clamp onto a number of flat surfaces, thereby allowing the system to be used with printed representations of keyboards, graphs, CRT monitors and standard television screens. The system is interfaced with any of a variety of computers and provides a signal representative of the location of the target to the computer.

Abstract: A circuit for measuring and indicating the separation distance between a vehicle and adjacent obstacles, consisting of a pulse controlled ultrasonic generator, an ultrasonic transmit-receive transducer connected to the generator for transmitting direct ultrasonic pulse signals to distant obstacles, and receiving these signals that are reflected from the obstacles, an amplifier and detector circuit connected to the transducer output for amplifying the received pulse signals, a first comparator which is connected to the amplifier and and detector stage, and a start-stop counter coupled to the output of the first comparator for measuring the difference in time between the end of the transmitted ultrasonic signal, and the reception of the reflected signal from the obstacle. There is also provided a noise suppression circuit coupled to the output of said first comparator and a second comparator coupled to both the output of the noise suppression circuit and the output of said start-stop counter.

Abstract: Method and apparatus for determining the length of a tubular member such as a pipe are disclosed. A burst of acoustical pulses are emitted from a sending unit and are received by a reference acoustical transducer and by a slave acoustic transducer. The slave transducer emits a return pulse which is used to compute the duration of the sound propagation interval between the ends of the pipe. A phase angle compensation factor is computed by measuring the phase shift of the signal received by the reference transducer with respect to the signal emitted by the master transducer.

Abstract: Method and apparatus for web break detection employing a sonic signal generator to generate regularly repetitive sonic signals of selected frequency, duration and time spacing between signals and disposed to direct the sonic signals toward a moving web of selected material so the signals are reflected from the web, a receiver device to receive the reflected signals, a time signal generating device to generate signal pulses during the time period between the generation of a sonic signal and receipt of the reflected signal a counter device to count the time generated between the transmission of the sonic signal and the reflected signal so that the number of time signals generated is indicative of the presence of the web as well as the distance of the web from the signal generator and receiver and a logic system to actuate a cutter mechanism to cut the web if it should fall outside a preselected "window" in which the web is positioned.

Abstract: Apparatus for detecting a load within a preselected bin of an automatic storage rack has a transducer for directing an ultrasonic beam into the bin and for detecting an echo reflected from a load struck by the beam; a digital counter adapted to generate plural bit binary pulses which is started upon initial transmission of the ultrasonic beam; and a programmable memory coupled to the counter and programmed to generate a given bin-ful output signal upon initial transmission of the beam and to subsequently generate the opposite binary bin-empty output signal if no echo has been detected when the pulses from the counter stored in the memory indicate that sufficient time has elapsed after initial transmission for the beam to travel a predetermined distance into the bin and for an echo from a load struck by the beam to return to the transducer.

Abstract: An ultrasonic echo-ranging system adopted to measure the level of liquid in an open channel or other liquid container. The system includes an ultrasonic transducer disposed at a fixed position directly above the liquid surface, the nature of the gaseous environment therebetween determining the velocity of ultrasonic energy propagated therethrough. The transducer is excited to emit periodic pulses which are directed along a center path toward the liquid surface and reflected to produce liquid echo pulses which return to the transducer and are detected thereby. A reference reflector at a predetermined position relative to the transducer intercepts energy from a side path in the radiation pattern of the transducer to return it to the transducer to produce reference echo pulses. Means are provided to determine the transit time of pulses along the center path, and also to determine the transit time along the side path.

Abstract: A distance sensing apparatus is provided in the form of a case housing electronic equipment including a piezoelectric transducer for radiating pulsed sonic or ultrasonic signals along a measurement path through a sound horn (3) which creates a narrow beam. Reflected signals received back through the horn are received by the transducer and converted into electric measurement signals. A time measurement device is providing for determining the time lapse between radiation of a pulse and receipt of a reflected signal so as to provide a distance signal which will be representative of the path distance between the apparatus and the surface which will trigger a display (7) to give a distance reading.

Abstract: A sonar fish counter, primarily for counting salmon migrating in streams and for providing a separate count of king salmon, includes a narrow beamwidth side-scanning sonar transducer directed to insonify a volume of water in the stream directly above a mechanical beam which serves as an artificial bottom. The transducer transmits pulses of short duration such as 100 microseconds at regular intervals. After a delay following a transmitted pulse, a receiver is enabled to receive echo signals from any fish crossing the artificial bottom. During the period the receiver is enabled, a ring counter separates the return echoes on the basis of the return time from respective sectors of the bottom structure, and these returns are separately counted for each sector so that the counts may be displayed or printed separately.

Abstract: An ultrasonic rangefinder system for use in either an ultrasonic rangefinder camera or a general purpose ultrasonic rangefinder designer's kit provides a plurality of automatic sonic rangefinder functions when embodied in the photographic rangefinder camera while at the same time accommodating independently established control functions overriding the automatic functions when the rangefinder is utilized as part of the general purpose sonar rangefinder designer's kit.

Abstract: A sonar device for use on a boat to indicate the depth of water on a digital display, including a transducer positioned in the water to transmit bursts of sound energy and for receiving echo energy reflected from the bottom, at least one variable gain receiver stage for amplifying the echo signals received by the transducer, a microprocessor for processing the amplified received signals to supply appropriate control signals to the digital display to indicate depth as a function of time required to receive echo signals, a means of controlling the gain of the receiver stage including a means with the microprocessor of supplying a plurality of paralleled output digital signals indicative of the required gain, means for converting the digital signal output to an analog gain control signal, and circuit means for applying the voltage gain control signal to the sonar receiver.

Abstract: A unique method for detecting and sampling flying insect populations is disclosed. An agricultural area is baited with a specific sex pheromone of a specific flying insect. When the flying insect is lured into range of the bait, a low-frequency sound is transmitted into contact with the insect. The sound is received in a counting means and the detection of the insect stored. Accumulated detections over a period of time form a population sampling of the insect studied.

Abstract: Apparatus for determining the location of the liquid level in a well or borehole. A source of acoustic pressure pulses is coupled to the surface casing so that they are transmitted down the well and reflected by the gas-liquid interface. A transducer is also coupled to the well to produce an electrical signal in response to direct and reflected acoustic pulses occurring in the well. Gating circuitry responds to the transducer for starting and stopping the counting of clock pulses by a digital counter. A digital readout device is used to indicate the depth to the liquid level in the well. The acoustic pulse source is automatically actuated at predetermined times, and the depth to the liquid level and the time are automatically recorded. This produces a record of time and liquid depth which can extend over a period of several days.

Abstract: A distance R to be measured is derived by measuring the spacing x.sub.m between a fixed transmitter Tx and a movable receiver Rx, and comparing this with the reference spacing x.sub.ref between a fixed transmitter Tx' and receiver Rx. Each spacing is measured by passing a large number of pulses sequentially from receiver to transmitter through a coupling medium, the receipt of one pulse triggering transmission of the next. The spacing is derived from the time T taken to pass n pulses; preferably n is fixed and T is measured.

Abstract: A sewer flow monitoring system wherein the depth of fluid in a pipe is measured in pairs of transmitter-receiver ultrasonic ranging transducers. Each measurement sample is tested against a selected range criteria and against other samples, and the determined good samples are then averaged. Short range detection capability is obtained by varying the response of signal processing wherein an attenuating effect decreases with time following a transmitted pulse.

Abstract: A depth determining device has features for informing the operator of the depth of the cutting tool of a hydraulic drilling machine. The drilling machine is for earth boreing and has a piston carried in a cylinder and secured to a driven kelly. The device has a transducer mounted at the top of the cylinder for transmitting a sound wave through hydraulic fluid to the tap of the piston and detecting the return of the wave at the top of the cylinder. A counter determines the elapsed time for the sound travel. The elapsed time is converted into depth and displayed.

Abstract: An automatic trolling depth controller is disclosed for a fishing boat employing a downrigger system. A sonar depth indicating unit with a sonar transducer continuously measures changing depth as the boat trolls. A depth control unit is connected thereto which automatically raises and lowers the trolling line via a reversible motor in response to depth indicating signals of the depth indicator unit so as to automatically maintain the end of the trolling line at a substantially constant given spacing from the bottom despite variations in lake depth as the fishing boat trolls.

Abstract: A depth sounder repeater providing a remote display of the depth of a body of water digitally or by meter movement, a depth alarm, a lost echo signal, and a meter scale expansion for shallow depth display in conjunction with a ship's sonar, display of "alarm depth" while setting. The depth display may be digital or analog and multiple displays are possible as required. The depth sounder repeater includes a signal processor for providing signals initiated with the main ultrasonic pulse transmission from the ship's sonar and terminated with the receipt of the first echo of the corresponding main transmitted pulses. The signal processor signals may then be used to initiate and terminate production of a train of clock pulse signals which are counted to provide a digital depth display, or alternatively the signal processor signal may be integrated in analog meter display apparatus.

Abstract: Apparatus for determining the location of the liquid level in a well or borehole. A source of acoustic pressure pulses is coupled to the surface casing so that they are transmitted down the well and reflected by the gas-liquid interface. A transducer is also coupled to the well to produce an electrical signal in response to direct and reflected acoustic pulses occurring in the well. Gating circuitry responds to the transducer for starting and stopping the counting of clock pulses by a digital counter. A digital readout device is used to indicate the depth to the liquid level in the well. The acoustic pulse source is automatically actuated at predetermined times, and the depth to the liquid level and the time are automatically recorded. This produces a record of time and liquid depth which can extend over a period of several days.

Abstract: An ultrasonic rangefinder providing a correct distance measurement and comprising a first transducer for transducing electric signals into ultrasonic waves and transmitting the ultrasonic waves, a second transducer for receiving the ultrasonic waves and transducing the ultrasonic waves into electric signals, a differentiation circuit, and a comparator for comparing a level of a differentiated output signal from the differentiation circuit with an output signal level of the second transducer and detecting a threshold time when the level of the differentiated output signal from the differentiation circuit becomes lower then the output signal level of the second transducer where a threshold signal level of the comparator is automatically varied with respect to a time lapse of the travelling ultrasonic waves coming back to the rangefinder after being reflected by an object, thus overcoming the conventional problems due to the spurious-like direct waves.

Abstract: A hand held, self-contained depth finding device is immersible into water for transmitting and receiving sonic impulses in the direction the device is aimed. The device includes a hand grip carrying a battery cartridge and an external trigger for operating a power switch within the waterproof interior. A liquid crystal display registers the measured depth in feet.

Abstract: A system for measuring the depth of the ocean, or other body of water, from a moving vessel uses acoustical sounding from the vessel and enables improved bottom definition during high-speed vessel travel. A succession of pulses of different tone frequencies is transmitted from the vessel. The echoes produced when these tone pulses reflect from the water bottom are received at the vessel and are sorted according to frequency. This arrangement assures that the determination of the transit time of a pulse at one frequency is not confused by receipt of an echo at another frequency. The transit times of the several pulses and their echoes are measured for use in determining water depth.

Abstract: An angling machine is electronically controlled with a digital indication of the fishing depth by counting the number of revolutions of the winder or reel spool of the machine. The apparatus comprises a converter for connection to the transmitter and the receiver of an echo sounder, a pulse generator and a plurality of counters being included in the converter for indicating the actual depth as determined by the time interval between two signals from said transmitter and said receiver, respectively, and a plurality of comparators coupled to respective ones of said counters for comparing the counts thereof with the counts of the counters indicating the fishing depth. The angling machine has circuit means controlling the fishing functions thereof by correspondence between the counts of the respective, corresponding counters.

Abstract: A system for locating and determining the distance to an object with respect to a movable vehicle is provided which utilizes at least three transducers wherein at least two of the three transducers operates either as a receiver transducer, in which case the remaining transducer operates as a transmitter transducer, or two of the three transducers operate as transmitter transducers in which case the remaining transducer operates as a receiver transducer with the system also including means for sequentially operating the three transducers for sending and receiving reflected ultrasonic signals to simultaneously determine both the location and distance of persons or objects with respect to the transducers.

Abstract: A system for measuring distance to an object. The system comprises a device for producing a high frequency sound impulse. There is a receiver for a high frequency echo sound impulse reflected from the object. A depth clock is connected to clock a counter. An initiator for the depth clock initiates the clock at a first time corresponding to the time of production of the high frequency sound impulse. The depth clock is stopped at a second time corresponding to the time of receipt of the echo sound impulse. The content of the counter is proportional to the distance to the object. A timer prevents stopping of the depth clock until a predetermined delay after the first time. A speech synthesizer produces spoken numbers corresponding to data supplied to the speech synthesizer. Data corresponding to the content of the counter are supplied to the speech synthesizer. The system is safer than prior art systems as it does not need to be observed.

Abstract: In an apparatus for guiding or controlling a vessel over the center of an unmarked channel, a pair of ultrasonic transducers are mounted athwartship on the hull of the vessel and directed downwardly to transmit ultrasonic pulses and to receive corresponding pulses reflected from the floor of the body of water. Time durations between transmitted and corresponding received pulses are measured to determine floor or channel depth below the port and starboard sides of the vessel. The depths are digitally encoded and supplied to a comparator which generates a signal indicating whether deeper water is port or starboard of the vessel. The comparator signal is supplied to a display to instruct the navigator whether to steer port, starboard or to maintain course to guide the vessel over the center of the channel. The comparator signal may be also supplied to a rudder servo to automatically steer over the channel center. A digital filter is provided to eliminate any spurious readings obtained by the transducers.

Abstract: A distance measuring apparatus installed in an automobile to measure with a high degree of accuracy a distance between a road surface and the axle of vehicle body of the automobile in motion. With this distance measuring apparatus, the distance between the point of its installation on the automobile and the road surface is measured by transmitting wave signals from the point of installation toward the road surface, selecting only the reflected wave signals of a predetermined intensity from the received reflected wave signals from the road surface and then integrating and averaging the data of the distance to the road surface derived from the selected reflected wave signals.

Abstract: A system for counting fish in a body of water uses one or more acoustic focusing liquid lens transducers each of which includes a large number of individual piezoelectric elements arranged in an arc to create a fan-shaped pattern of adjacent beams, each of which has a narrow beam width. An electrical counting circuit includes a clock producing a series of timing pulses supplied to a plurality of binary coded decimal (BCD) actuated switch circuits, one of which initiates sequential operation of transmit pulses from individual transducer elements. Timing of receiver operation is also controlled by said timing pulses after a delay to minimize "ringing" of the transducer elements from the transmit pulses. Received echo signals are amplified, threshold detected and converted to uniform pulses.

Abstract: A navigation aid for determining berthing data comprises distance detecting units embodying sonar transducers which are spaced apart along the length of a jetty a short distance behind the berthing line. The units are operative to provide signals indicative of the distance from the berthing line of correspondingly spaced sections of the ship, and a microcomputer selects two out of three of these signals and processes them to determine the distance from the berthing line of nominal bow and stern sections of the ship, the nominal measuring points being different from the actual measuring points at which the transducers are positioned. The microcomputer also processes the selected signals to determine the velocity of the bow and stern sections relative to the berthing line, and controls a jetty display of the determined distance and velocity data in addition to local and remote indications/recordal thereof.

Abstract: An improved sound ranging system increases the precision of range measurement by automatically correcting for any variation in the velocity of sound in the medium. The automatic correction for the sound velocity utilizes a small sound reflecting target located at a precise fixed distance from the transducer surface. A digital circuit, including a microcomputer, improves the measurement accuracy of the system. The invention includes a time delay and sensitivity control in one of the two time measurement circuits employed in the system to prevent "ghost" signals caused by multiple round-trip target reflections from introducing errors in the range measurements.

Abstract: An underwater mapping system in which a swath of terrain, much wider than a sonar beam width, is observed by means of a sonar beam scanned in the cross track plane of a ship. Filtering and correlation techniques are employed to compensate for distortions in echoes emanating from the ocean bottom by a selection of filter coefficients in accordance with the orientation of the sonar beams and by providing a simulated echo envelope for correlation.

Abstract: A method and apparatus for indicating the level of liquid in a tank or the like whereby a transducer is mounted on a pipe above the liquid for producing, in response to a trigger signal, an ultrasonic pulse which is transmitted toward and reflected to the transducer first from a calibration target in the pipe above the liquid and then from the liquid so that the transducer produces echo pulses in response to receipt thereof. In one embodiment the calibration echo signal is applied to a logic circuit together with the output of a counter which is incremented to a predetermined count following the trigger signal by pulses from a voltage controlled oscillator so that the logic produces a control signal indicating the difference in time between when the calibration echo is received and when the counter reaches its predetermined count and which event occurs first. The logic then varies the frequency of the oscillator to reduce the difference.