Abstract: A position and seal or packing wear indicator for mechanical flow controlling devices such as valves and blowout preventers. For blowout preventers the system includes ultrasonic sensors for each ram and annular blowout preventer of a blowout preventer stack. Each of the ultrasonic sensors is positioned within the wall structure of the valve or blowout preventer and is recessed with respect to the inner wall surface such that a desired echo thereof occurs at the plane of the inner wall surface, thereby rendering the electronic signal processing system capable of accurately and positively sensing the precise positions of the flow controlling devices at all times. Electrical signals from the ultrasonic sensors are converted by an electronic signal conditioner to a usable interface format for transmission through a multi-conductor cable system to a remotely located computer. The computer includes software which generates on its CRT a graphical display of the respective positions of the flow controlling devices.

Abstract: A method of and a device for safeguarding a vehicle or machinery movable in space, such as a robot, a stacker, an operatorless transporting vehicle or the like against collision, in which by the use of distance sensors, especially ultrasonic sensors with echo time measurement, the distance from an obstacle is measured and a reaction signal is initiated when a preset threshold value is not reached, said method and device being characterized by a time-synchronous actuation of the distance sensors in a compound circuit which in case of a dangerous approach of the vehicle to an obstacle triggers a reaction signal which is either a speed reduction signal or a stop signal. Moreover, the measuring signal can be utilized as a command signal for actively influencing the vehicle movement, e.g. for driving around the obstacle or the like.

Abstract: An ultrasonic distance sensor transmitting from and receiving an ultrasonic wave with a single ultrasonic transmitting and receiving element to measure proximate distances such as vehicle floor heights or distances to obstacles or pedestrians approaching relative to a vehicle. The ultrasonic transmitting and receiving element is accommodated by means of a resilient member having beads, under pressure in a casing and secured therein, thus attenuating residual vibration which disturbs accurate measurement of the proximate distances. The beads also serve to prevent water from invading into the case. The sensor incorporates a protection circuit for preventing burn-out of an output transistor due to accidental prolonged transmission.

Abstract: Acoustic delay means are interposed between the face of a transducer and the bottom of a vessel, with the delay being equal to or greater than the shallowest depth the associated depth sounder capable of, whereby subtracting out the depth associated with the acoustic delay, the water under the vessel can be measured down to zero feet. In a preferred embodiment, a water column is utilized as the delay media, with the transducer being mounted at the top of the water column and with the water column being terminated at the bottom of the boat. The transducer pulses are projected through the water/hull/water interface to the water beneath the vessel. For digital depth sounders, the depth associated with the water column may be subtracted out to give the zero reading.

Abstract: An ultrasonic measuring transducer system in which an ultrasonic transducer transmits an ultrasonic pressure wave and receives a return echo from a target and an electronic circuitry means converts the received pulses to arrange information to a target. The ultrasonic transducer is mounted in a wall of a plenum chamber. Air flow passages or apertures surround the ultrasonic transducer and air from a supply under pressure is connected to said plenum chamber. A temperature (or velocity of sound) measuring device is mounted in the plenum chamber for measuring the temperature from which the speed of sound in the medium is determined, and a measuring chamber forming tube surrounding the transducer and air outlet apertures provide a space in which air flow is maintained at a relatively constant rate and the temperature in substantially all of the measuring path and space between the target and said ultrasonic transducer is essentially the same as in the plenum chamber.

Abstract: Apparatus for measuring distances comprising circuit for sending an acoustic signal to a distant location, the distance of which is to be measured, circuit for receiving back reflected acoustic energy, and electronic circuit means for eliminating spurious echoes by providing a threshold signal level above the signal level of said spurious echoes, and a timing circuit to time the interval between the transmission of the acoustic signal and receipt of the acoustic signal.

Abstract: Echo locating apparatus for a vision-impaired person which includes: a sound emitter for emitting a stream of sound bursts of ultrahigh frequency; at least on receive channel having a microphone for receiving echoes of the sound bursts and generating echo signals; an echo profile detector for generating an echo profile signal of each echo signal; a delay circuit for adding a delay to the echo profile signal, consisting of the sum of a fixed delay and a variable delay that increases with the distance to the object reflecting the echo. The sound burst emitter is preferably arranged to emit a beam of sound bursts having a given beam angle that can be pointed in any direction.

Abstract: A distance detecting apparatus has a transmitter for transmitting a cyclic output signal. The transmitter is digitally controlled to adjust the frequency of the output signal in relatively small increments through a band of frequencies. A receiver receives a cyclic reflected signal and has an adjustable center frequency of response. There is a device for adjusting the center frequency of response to correspond to the frequency of the output signal. The apparatus may have digital control for controlling the power level of the output signal. There may be a digital control for the gain of the receiver. The apparatus may also include a transducer for converting electrical signals to ultrasonic signals and include controls for adjusting the frequency of the output signal according to requirements of the transducer.

Abstract: Distance measurements are made using two or more signal frequencies. Ultrasonic energy is transmitted from a transducer to an object. Returned ultrasonic energy is received by the transducer and processed to provide an accurate determination of the distance between the transducer and the point on the object receiving the ultrasonic energy. In connection with the processing, a number of relationships are utilized. Using certain of the relationships, a range of integers is determined using high and low frequency ultrasonic energy, as well as propagation time. A time-related phase shift determination is also made for each of the high and low frequencies using certain of the other known relationships. Using a range of distance values and the measured time-related values, an accurate determination of distance from the transducer to the object can be made. In one application, a number of different distance values are obtained to define the surface plane of the object, such as a wheel or tire.

Abstract: The minehunting system includes a remotely operated vehicle which is driven ahead of a vessel. The vehicle is equipped with a sonar system for detecting, classifying and disposing of a mine.The sonar system comprises an acoustic mirror sonar which includes a dual field-of-view reflector, a height finding element and a dual frequency classifier.The vehicle has a autopilot which, is conjunction with control algorithms in a shipborne tactical computer on the vessel provides navigation and manoeuvering commands.

Abstract: In the field of the echography, the present invention is a system and method of preprocessing and transmitting information (such as echo waveform information) from a source (such as a transducer) to a destination (such as a rule-based computer system). The present invention reduces the absolute amount of information that is transmitted without reducing the amount of meaningful information that is conveyed. In this way, the present invention is effectively able to transmit more meaningful information than would be expected for conventional transmission systems. It also acts to reduce the amount of information processing that must be done at the destination.

Abstract: This invention provides an icing preventive device for a supersonic wave transmitting and receiving unit for a vehicle which is composed of a timing device for outputting a timing signal, a supersonic wave transmitting and receiving device for transmitting a supersonic wave signal and receiving a reflected wave in response to the timing signal, a received signal processing device for amplifying the received signal caused by the reflected wave and processing the waveform of the amplified signal, a control device for controlling a vehicle load in response to the received signal of which waveform is processed, a temperature sensing device for sensing a temperature outside the vehicle, a heater operating device for energizing and heating the heater in response to both decrease in the temperature outside the vehicle and a level of the received signal of the reflected wave, and a heater arranged in the supersonic wave transmitting and receiving device, and further the present invention discloses the technology of t

Abstract: In acoustic level sensing apparatus, in which pulses of acoustic energy are transmitted by an electrically energized transducer towards a surface to be sensed, and the electrical output from the transducer following the pulse is digitized and analyzed to detect a return echo from the surface, so as to produce a digitized echo profile. The digitized echo profile is enhanced by removing narrow peaks likely to correspond with certain types of spurious echo, and narrow valleys which may represent fragmentation of a wanted echo. Echoes are identified by comparing the profile with a time varying threshold generated derived from a linear regression performed on part of the threshold, various different types of comparison being performed and their results combined prior to selecting the most likely true echo on the basis of the combined results.

Abstract: An improvement in a capacitance type electrostatic transducer for transmitting and/or receiving pressure energy, wherein the transducer includes a relatively inflexible backplate with at least one major surface thereof formed of electrically conductive material, a relatively flexible membrane including a layer of electrically conductive material stretched across and coextensive with the one major surface of the backplate, electrically insulating means for maintaining a capacitor forming spacing between the major surface and the stretched membrane and wherein the major surface has protrusions extending through the spacing for supporting the membrane. The improvement is providing the protrusions as a multitude of discrete pedestals distributed over the major surface and formed by etching away the major surface except in photographically selected areas defining the pedestals.

Abstract: A sonar fish finder system is provided for a boat for determining and displaying the location of fish in the body of water surrounding the boat. The system includes an electromechanical transducer assembly for transmitting sound waves in the body of water along separate paths in different directions into separate areas of the body of water, for receiving corresponding echoes from obstructions in the paths (including echoes from any fish in the paths) and for generating electrical signals in accordance with the received echoes. Electrical transmitters connected to the transducer assembly control transmission of the sound waves and receivers, connected to the transducer assembly, receive and process the electrical signals produced thereby.

Abstract: In a system for detecting the position of an object having predetermined design features in a plane relative to a manipulator provided with ultrasonic sensors consisting of ultrasonic transmitters and ultrasonic receivers, the manipulator is provided with at least three ultrasonic sensors, which are spaced apart and directed at an angle to a common reference plane, two of the sensors are directed to an elongate linear design feature of the object, the third sensor is directed to a second linear design feature of the object, the linear features are designed so that sound waves projected by the ultrasonic sensors and incident on the features will be reflected parallel to the direction of incidence, and the two linear design features are parallel to each other in a plane.

Abstract: In one embodiment of a technique for monitoring scouring around structural members which are at least partially submerged in the soil bed material at the bottom of a body of water, the distance between a fixed point on the structural member and the topmost portion of the soil bed material near the member is determined and compared to a predetermined value. When scouring occurs, removal of some of the soil bed material results in an increase in the measured distance, which increase can be used to indicate the occurrence of scouring in an appropriate manner, such as by utilizing a display, by recording the data, or even by telecommunicating the data to another location. The distance determination may be made either only when called for or periodically at predetermined times, in order to provide continuous monitoring. In an alternative embodiment, scour monitoring is provided by one or more probes disposed so as to initially rest on top of the soil bed material located near the structural member.

Abstract: A method and apparatus for use in a pulse-echo imaging or ranging system comprising means (32) for identifying the analytic signal from a received signal and means (34) for extracting ranging information from the analytic signal. The analytic signal can be obtained and processed by digital or by analog circuit means. One embodiment of the analog circuit means (32) includes means (90) for modulating the received signal on a carrier frequency, means (92) for obtaining a single sideband signal from the modulated signal and means (94) for envelope detecting the single sideband signal.

Abstract: A receiver for active sonar systems comprises two fundamentally different detection processes operating simultaneously with the output of each detection process being combined by a computer utilizing a computer-aided detection algorithm. One detection processor is a segmented replica correlator (SRC) and the other detection processor is a polarity coincidence correlator (PCC). Each detection processor provides to the active computer-aided detection algorithm a list of ranges and bearings of a relatively small number of detection events. The computer algorithm operates on these events to compare events from the current ping and the previous ping for each of the processors.

Abstract: Microprocessor controlled industrial monitoring equipment uses a separate portable keypad which can be applied to a sealed casing containing a control unit to transmit commands and calibration to the equipment, which normally operates and provides a display of information in the absence of the keypad. The equipment is usually acoustic level sensing apparatus, in which pulses of acoustic energy are transmitted by an electrically energized transducer towards a surface to be sensed, and the electrical output from the transducer following the pulse is digitized and analyzed to detect a return echo from the surface.

Abstract: Range finding equipment is employed in a nuclear reactor to monitor the spacing between structural components (22, 24) of the reactor which are under stress. A manipulator (32) carries a pair of send-receive ultrasonic transducers (30) arranged back to back so as to direct ultrasound signals towards reflectors (26, 28) associated with the structural components to be monitored. The transducers are pulsed with signals derived by gating a few cycles of a sustained reference signal of sine wave form and the resulting echo signals can be used to provide transit time and phase displacement information from which the spacing between the relectors (26, 28) can be derived with a high degree of precision.

Abstract: A method of measuring the depth of a microcrack. A sample which has a crack substantially parallel to the surface and slightly inclined is set in the neighborhood of the focal point of a converging acoustic beam, and the depth of a microcrack of the sample irradiated with the beam is measured on the basis of the phenomenon that the reflected wave intensity assumes a minimum value when the product of the crack depth and the frequency of the acoustic wave is equal to a half integral multiple of the velocity of the acoustic waves in the sample.

Abstract: A sensing arrangement for sensing the level of a bulk material, such as the paving material fed by a paving machine, comprises an ultrasonic transducer spaced from the paving material for controlling the feed of material.

Abstract: An apparatus measures changes in groundwater pressure in a borehole. The apparatus comprises: a probe consisting of a hollow tube having a smooth interior surface, an ultrasonic transmitter which emits ultrasonic waves down the interior of the tube, and an ultrasonic receiver which receives and registers the reflected ultrasonic waves; a means to raise and lower the probe so the tube is partially submerged in the groundwater; a means to control the emission of ultrasonic waves; a means to convert the time interval into a distance or pressure measurement; and a means to store or transmit the data.

Abstract: An improved ultrasonic ranging device having a ultrasonic sensor unit provided for detecting the distance between a ground object and a rear end of a vehicle includes: a casing body composed of a front casing and a rear casing with a round opening formed in the opposing ends; a control unit with a plurality of microswitches and a control circuit installed at one end of the casing body and electrically connected to the ultrasonic sensor unit; a gear system with a motor and a reduction gear member disposed at another end of the casing body and electrically connected to the control circuit; and a protective cover with a transmission arrangement movably connected to the casing body with the transmission arrangement meshed with the reduction gear and the control unit; thereby, the protective cover can be automatically raised up and lowered down along with the backward and forward movements of a vehicle for protecting the ultrasonic ranging device against water, dust and mud.

Abstract: An ultrasonic air spring system adapted to be mounted on a vehicle for absorbing road shocks exerted on the vehicle and for maintaining the vehicle body level with respect to the axles. An air spring includes an end plate and a piston sealingly connected to the open ends of the flexible elastomeric sleeve to form a pressurized fluid chamber therebetween. A transducer is mounted on the end plate within the fluid chamber and transmits ultrasonic signals through the fluid chamber toward the piston and picks up reflected signals therefrom. A signal is generated by the transducer in response to the reflected signals and fed to a microprocessor based control module. The control module determines whether the air requires fluid feed or exhaustion and will then implement control of inlet or exhaust valves to achieve a desired axial separation between the end plate and piston.

Abstract: An ultrasonic rangefinder capable of detecting a distance between a vehicle and an object with high accuracy is shown. The measure of microphones for transmitting and receiving ultrasonic waves is chosen so that detour waves are restricted.

Abstract: The present invention provides a method and device for determining the positioning of an element or target using at least one acoustic emitting-receiving sensor. In this method only the signal received by said sensor and due to the diffraction of the signal emitted by said sensor is taken into account.

Abstract: A range control system positioned within a stationary housing comprising: a pulse oscillator for providing a clock signal; and a transmitter receiver circuit that directionally transmits an acoustic pulse signal to a target and receives an echo from the target to provide an amplified echo signal. A timing circuit means is included for providing a range gate signal characterized to start with each clock signal and to have a predetermined duration characterized to provide a time for the acoustic pulse to travel to the target and for the echo to return from the target. An alarm signal is provided to indicate that an echo signal is being received prior to the termination of the range gate signal. A ring blanking gate signal source provides a ring blanking gate signal commencing with each clock signal and having a duration longer than the tailoff ringing of the acoustic pulse. A diode clamp is coupled to the transducer drive circuit echo signal output.

Abstract: An apparatus for detecting the distance of an object from a signal transmitter during radiation of a transmitter signal uses a first capacitor which is initially short-circuited by means of a first switch and subsequently is charged from a constant current source following an opening of the switch. Upon a reception of an echo signal, the charge of the first capacitor is transferred to a second capacitor by closing a second switch at the time of the echo signal reception. The charge on the second capacitor, which is proportional to the elapsed time between transmitted and received signals, is delivered to an output via a low pass filter with the output signal representing a distance measuring signal.

Abstract: A method and apparatus for the sounding of waters, particularly suitable for depth (and the like) sounding of Arctic waters, comprises shooting an energetic projectile at the water or ice surface from, say, a helicopter which has suspended close to the waters surface a suitably housed microphone for receiving the echo energizing from the waters. By measuring elapsed time between firing of the projectile and reception of the echo, and knowing all distances except the depth of the reflecting boundary (be it the bottom or a submarine), the unknown depth is easily determined.

Abstract: An ultrasonic transducer and method for detecting the distance to an object using ultrasonic energy. The transducer includes a foil which creates ultrasonic energy. First and second reference surfaces are provided which are spaced between the transducer and the object. The two reference surfaces provide for immunity against temperature and positional changes.

Abstract: A method for processing a reflected echo signal which is received from an object and supplied to an ultrasonic binaural sensory aid comprising the step of stretching said reflected signal in time axis, and the step of converting the stretched signal into a signal of audible frequency, and a blind aid which works by the above mentioned method.

Abstract: A distance detecting device having a transmitter for intermittently transmitting measuring waves toward an object, a pair of receivers provided so as to be spaced from each other by half the wave length of the waves in a direction of the object, each receiver receiving reflected waves from the object and transmitting a reception signal responsive to the amplitude of the reflected waves, an addition circuit for adding the reception signal from each of the pair of receivers and transmitting an addition signal, a peak detection circuit for detecting a peak of the addition signal and transmitting a reflected waves reach signal at the time of peak detection, and an operation device for calculating the distance to the object based on the return time from the time when the waves are transmitted to the time when the reflected waves reach signal is outputted.

Abstract: An ultrasonic rangefinder capable of detecting a distance between a vehicle and an object with high accuracy is shown. The measurements for microphones for transmitting and receiving ultrasonic waves are chosen so that detour waves are restricted.

Abstract: An acoustic inspection system includes acoustic transducers to transmit and receive continuous acoustic waves at a constant frequency. Changes in phase and/or amplitude of acoustic waves reflected at different times from a fixed reference target through an isothermal transmission medium are detected. The temperature of the acoustic transmission path is controlled in response to the detected phase changes to maintain the wavelength of acoustic waves constant independent of changes in humidity and barometric pressure.

Abstract: Apparatus for sensing distances in air by transmitting an ultrasonic pulse and measuring the time for return of an echo from a target object is characterized by ability to measure distances to multiple target objects. Preferably the apparatus defaults by displaying the distance to the nearest target but is provided with a push button which when pressed once causes display of the distance to the next target further away, when pressed again causes display of distance to a target after that and so forth. This novel function may be accomplished by discrete logic components or using a microprocessor.

Abstract: An underwater detection system display underwater conditions on an indicator comprised of a monochrome cathode ray tube with two groups of different degrees of brightness. One group of different degrees of brightness is related to the amplitude of echo signals in such a way that degrees of brightness are in direct proportion to the amplitude of an echo signal. The other group of different degrees of brightness has another relationship with the amplitude of an echo signal.

Abstract: A self-calibrating ultrasonic distance sensing method and apparatus are disclosed in which a transducer periodically transmits a pair of bursts of acoustic energy along an acoustic path toward a target object. Echoes of the first acoustic burst in the burst pairs from a reference target at a known distance from the transducer are used for calibration purposes, and echoes of the second acoustic bursts in the pairs are used to determine distance to the target object.

Abstract: Obstruction detector apparatus operatively coupled to an automatic electric door operator compares the time span of transmission and receipt of reflected echoes of ultrasonic energy within a door passageway obstruction zone with predetermined time spans in order to prevent door closure under conditions indicating passageway obstruction or system malfunction. Signal generators provide timing signals respectively representative of the anticipated time span of reflected echoes from locations in front of, and beyond, the door jamb opposite the ultrasonic transmitter and receiver transducers for comparison by a relay controller with the time of generation of a signal representing a reflected echo at the transducer receiver, the relay controller appropriately actuating a door operator relay in response to such comparison.

Abstract: The invention concerns an application of linear system parameter estimation techniques to finite amplitude sonar devices, to extract fine grained angular position information about echo sources. The invention makes use of the fact that the waveform return by a reflecting object within the sonar's beam varies according to its relative angular position from the receiver, and a discovery that this variation may be fit to a linear system model using autoregressive estimation theory to extract the nature of the variation. In all cases, the information is extracted without the mechanical or electrical steering of the sonar transmitting beam.

Abstract: A cylindrical member for preventing a roundabout of the supersonic wave is arranged around the transmitting and receiving opening of one of the sender or receiver of a supersonic wave device for a vehicle which is installed on the vehicle. Thereby the phenomenon of the roundabout of the supersonic wave is reduced and at the same time the duration time of phenomenon of the roundabout of the supersonic wave is decreased and the object of the short distance can be sensed.

Abstract: An ultrasonic distance sensing method and apparatus are disclosed in which a transducer periodically transmits a pair of bursts of acoustic energy along an acoustic path toward a target object, an echo of the first acoustic burst in each burst pair is used to establish a peak reference level, and an echo of the second burst in each pair is used to determine distance to the target object only if its level exceeds a predetermined fraction of the peak reference level.

Abstract: An ultra-sonic sensor includes a driver circuit outputting a high-frequency driver signal which orders a transmitter to transmit ultra-sonic waves toward a target object. The driver circuit also sends the driver signal to a receiver. The driver signal is superimposed on a receiver signal. The receiver differentiates the receiver signal and compares the differentiated receiver signal level to a threshold level to detect reception of the reflected ultra-sonic wave. The receiver also detects when the transmitter is actively transmitting the ultra-sonic waves toward the object and disables the aforementioned comparison at such times. Accordingly, by comparing the differentiated receiver signal level with the threshold, the influence directly transmitted ultra-sonic waves on detection of the reflected ultra-sonic wave is successfully avoided.

Abstract: An ultrasonic vehicle rangefinder having a detecting system for discriminating whether trouble is in transmission or reception side is shown. The discrimination is established by detection of an attenuation vibration at a transmission microphone.

Abstract: The sonic or ultrasonic distance measuring device used for example to measure the filling level in a container comprises an electroacoustic transducer which operates alternately as transmission transducer for the transmission of sonic or ultrasonic pulses and as reception transducer for the reception of the reflected echo pulses. Connected to the transducer is a signal processing circuit which includes an amplifier with controllable gain and a threshold value discriminator. A gain control circuit controls the gain of the amplifier during a predetermined period after the start of each transmission pulse in accordance with a stored function which is fixed in accordance with the dying-down behaviour of the transducer so that the electrical signals originating from the dying-down of the transducer after amplification are smaller than the threshold value of the threshold value discriminator but are as close as possible to said threshold value.

Abstract: From a first aspect this invention provides a missing pulse detector for determining the true termination time of a sequence of pulses in a signal of an assumed predetermined length having a rising edge and a trailing edge which may include pulses which do not reach a predetermined threshold, the detector including a counter connected to count pulses exceeding said threshold, up to a predetermined number, an oscillator for producing pulses at twice the frequency of the pulses in the signal and an enabling circuit for allowing pulses from the oscillator to pass to the counter only after the termination of a sequence of threshold-exceeding pulses from the signal.

Abstract: The device comprises at least two ultrasonic transducers emitting focused radiation and a circuit making it possible to measure the difference between the sampled signals supplied by these two transducers. This difference is cancelled out when the probe faces the object.Application to metrology and the position control of objects.

Abstract: An ultra-sonic distance sensor system includes means for measuring the elapsed time between transmission of ultra-sonic waves and receipt of the return wave reflected by an object which reflects ultra-sonic waves and the distance to which is to be measured. A correction value is derived on the basis of the rate of change of the signal level of a receiver signal output by an ultra-sonic receiver. On the basis of the derived correction value, the resultant distance value or the measured elapsed time value is corrected to ensure accurate measurement of the distance to the object can be ensured. This allows more precise height control for a vehicle when the distance detector is applied to a height control system of an automotive vehicle.

Abstract: A double reference pulse phase locked loop for measuring the phase shift between tone burst signals initially derived from the same periodic signal source (voltage controlled oscillator 16) and delayed by different amounts because of two different paths. A first path is from transducer 12 to surface 14 of sample 11 and back, and a second path is from transducer 12 to surface 15 and back. A first pulse phase locked loop including phase detector 26 and phase shifter 22 forces the tone burst signals delayed by the second path in phase quadrature with the periodic signal source. A second pulse phase locked loop including phase detector 21 forces the tone burst signals delayed by the first path into phase quadrature with the phase shifted periodic signal source.