Abstract: A triaxial force sensor using a hemispherical target embedded in a compliant layer such as an elastomer and having a plurality of ultrasonic transducers disposed in a plane at equal intervals about the target and vertically and laterally offset from the target. The transducers are oriented at an oblique angle to the plane, and aimed at the target in its rest position. The target is displaced by sufficient force applied to the surface of the compliant layer, which displacement alters the transit times of ultrasonic signals from the transducers which are reflected from the target. If at least three sensor units are employed non-colinearly, the six force-torque components, F.sub.x, F.sub.y, F.sub.z, M.sub.x, M.sub.y, M.sub.z, can be determined from the pulse transit times, the speed-of-sound in the compliant layer, the compressibility of the compliant layer, and the known geometry and spacing of the sensor units.

Abstract: The method and the device for detecting flaws in materials and their connections comprise the radiation of ultrasonic rays and the reception of that energy after its reflection from the examined product, wherein the component which creates, radiates and receives the ultrasonic energy is comprised of a number of interconnected sub-plates. The focused energy which penetrates the metal has a special form appropriate to the type and shape of the product. The sub-plates are mechanically connected to a cylindrically-shaped base, and electrically interconnected by adjustable electronic control means which appropriately change the characteristics of the sub-plates when necessary. The bases of each sub-plate system are made of a material transparent to ultrasonic rays, for example plastic, and the contact surfaces of the bases of each of the sub-plate systems are fortified by grooves filled with a wear-resistant material.

Abstract: A multizone ultrasonic inspection apparatus and method of employing the apparatus for inspecting titanium billets is provided, in which a plurality of ultrasonic transducers having focal zones of increasing depth are positioned to examine a cylindrical billet of titanium through the thickness of the billet. The focal zones partially overlap the adjacent focal zones, thus assuring complete examination through the thickness of the entire billet. The reflected signals from the transducer receivers are processed into digital form in order to be used in generating an image of the billet undergoing inspection, and to be used in storing the image data in, for example, a hard disk or an optical disk.

Abstract: A phased array ultrasonic imaging system performs a scan in which beamforming time delay errors due to nonuniformity in ultrasound speed within the transmission medium are corrected by estimating and correcting phase aberrations in accordance with the maximum likelihood theory. The system employs a multiple-channel transmitter and receiver, and estimates phase values, not phase difference values, thereby eliminating any need to perform an integration to produce the phase aberration profile. The method can be implemented in real-time, allowing correct data to flow out of the circuit which at the same time can be receiving new input data. Delays can be added to allow for phase aberration correction of past measurements. The method allows tracking, to some extent, of variations that may occur in the phase aberrations. Depending on the number of channels that are simultaneously considered, different closed loop circuits can be employed.

Abstract: A method and a device for operating an ultrasonic sensor, in which the measuring sensitivity is monitored and the measuring result is compensated for temperature. This is accomplished by measuring the distance of a fixed marking, which is situated on the vehicle and has a known distance from the ultrasonic sensor, to extract a signal, whose amplitude is a measure of the sensitivity of the ultrasonic sensor. From the measured delay time and the theoretical delay time to the marking, a value is attained, which is a measure of the temperature of the ambient air. Suited as a marking is, for example, an edge of a raised license plate frame, which is mounted on a bumper bar of a motor vehicle and lies within the detecting range of the ultrasonic sensor.

Abstract: A shoe (1) is provided which includes two housings designed for receiving ultrasonic probes (2) of which the vertical position with respect to the track is adjustable via two pressure cylinders (9). The shoe (1) is connected via two pressure cylinders (13) to a frame (12, 22, 23) designed for mounting under a railway vehicle. The shoe (1) is guided and driven along the track by deformable rings (14). Conduits (15, 16) are arranged in the body of the shoe (1) in such a manner as to allow the supply of a fluid in front of the probes (2) and the recovery of one part of this fluid behind said probes (2). Cleaning shoes (30, 30') and high pressure sprayers (31, 31') clean the track in front of the measuring carriage.

Abstract: An ultrasound testing device for gas pressure accumulators is used to test a predeterminable set position that can be taken by a movable separating element inside an accumulator filled with gas and connected to a fluid circuit. The separating element has at least one testing body associated with a visible mark which indicates the set position of the separating element. An ultrasound testing device on a testing body can be set on the accumulator in alignment with the visible mark. This testing device allows a plurality of accumulators of the same type to be tested for their predeterminable gas pressure set value, which corresponds to the gas pre-filling pressure, by a single hand apparatus. This kind of test is economical and achieves reliable results.

Abstract: A method and apparatus for detecting internal defects in a workpiece are disclosed which uses time inversion to invert echo signals received by a transducer from the workpiece with respect to the signal shape and its time distribution and retransmits the inverted signal onto the workpiece. The method involves transmitting an unfocused ultrasonic beam onto the workpiece, receiving an echo signal from the workpiece, storing the first echo signal and inverting the first echo signal from each transducer with respect to the signal shape and time sequence. The inverted signal is transferred to a memory and the aforementioned procedure is carried out for each of the inspection zones n on the workpiece. The stored, inverted first echo signals are then transmitted onto the workpiece, each inverted signal being transmitted onto the inspection zone n from which the non-inverted first echo signal was received.

Abstract: In the process whereby a time gate but especially the time gate for an expected error range 58 in a device by means of which materials are tested by ultra sound according to the impulse echo process involving a test head 20 which emits pulses that impinge diagonally on the surface 28 of a test piece 24, the test head 20 that emits diagonally is firmly connected to a test head 22 from which pulses are emitted vertically. Both test heads emit at given intervals 48, 49 ultra sound impulses and subsequently receive them. The echo signal 50 of the entry of sound of the test head 22 from which pulses emit vertically is utilized to activate the time gate of the test head from which sound is emitted diagonally.

Abstract: The invention relates to an ultrasonic process for testing, by immersion, the soundness of a metal piece (26) using at least one transducer (21) emitting ultrasonic waves focused in the piece (26). There are a plurality of transducers (21) used. Each of the transducers having in the tested piece (26) a focal spot at -6 dB, the section of which, perpendicular to the axis of propagation of the waves is less than 40 mm2. The focal spots of the transducers (21) being distributed depending on the depth to be tested of the piece (26). Additionally, the invention describes a process to guarantee the soundness of the interior of a piece (26), in particular a bar made of a titanium alloy (26) of a diameter of between about 50 and 400 mm for use in aeronautics.

Abstract: Techniques for providing an ultrasonic flaw detection system are disclosed. A continuous wave of wide-band direct-sequence spread-spectrum signals continuously drives one or more transmitting transducers, thereby flooding a test object with coded ultrasound. In operation, the ultrasonic testing system is capable of reliably and predictably transmitting a high degree of ultrasonic energy (power) to a test object. Code division multiplexing correlation techniques using a variably delayed replica of a selected segment of the DSSS signal are applied to the signals received by the receiving transducers to generate a signature representing the signal returned from all reflectors within the test object.

Abstract: A method and an apparatus are provided for measuring the wall thickness of a pipeline through which a fluid flows, the pipeline having an interior and exterior surface. The apparatus has a pig body supported by elastomeric cups to thereby cause the pig body to move by fluid flow through the pipeline. The pig body supports a plurality of multi-element transducers. Each transducer is made up of a large number of independent elongated rod-like crystal elements separated by a polymer, each having side walls, a front face and a bottom face. The rod-like elements are arranged so that the side walls are adjacent but mechanically isolated from each other, such as by an epoxy, with the front faces and bottom faces providing transducer front and bottom surfaces. A front metallic film and a bottom metallic film are applied to the front and the bottom surfaces. Each transducer is configured to have an impedance that closely matches the impedance of the pipeline fluid.

Abstract: An improved method for repair of incore-instrumentation-housing and related defects in a nuclear reactor system involves three stages, each with ultrasonically assisted inspections. In the first stage, a defective incore housing is removed and the exposed area and aperture at the former location of the incore housing is ultrasonically inspected using an ultrasonic probe with a tiltable disk-shaped head that self-conforms to the local contour of the reactor vessel bottom. In the second stage, a weld buildup is formed. The reactor is then sealed and the weld buildup is machined to define an aperture therethrough. The weld buildup is then ultrasonically inspected with a second probe with a centering member that is stationary as the probe body is moved vertically relative to it. In the third stage, a J-prep is formed. A new incore housing is inserted through the weld buildup aperture. The new incore housing is welded at the J-prep. The J-weld is ultrasonically inspected using a third ultrasonic probe.

Abstract: A probe 10 and method for measuring a gaseous material, such as air, entrained in a solution (S) has a protective sheath member 14 having an ultrasonic transducer 18 encased therein and a reflecting member 42 spatially separated from the active area of face 20 of transducer 18. Upon activation of transducer 18, ultrasonic waves are emitted from transducer 18 that reflect off the gaseous material in the form of bubbles 48 and reflecting member 42 thereby producing correspondingly associated backscattered signals therefrom. Accordingly, the backscattered measurement is operative at low entrained air levels when only a few bubbles or gas 48 are present. Scattering from reflecting member 42 is useful at higher entrained air levels, approaching foam.

Abstract: An ultrasonic system is provided for measuring the thickness of steel plates used in the bottom of oil storage tanks and other similar applications. When the bottom plate corrodes, the potential for leakage occurs. The ultrasonic system can be used to monitor the corrosion of bottom plates in areas which are generally inaccessible, such as the bottom of oil storage tanks. The ultrasonic system includes a probe drive frame having multiple brackets for supporting a plurality of ultrasonic probes. A pulse generator and multi-channel scanner are connected to the probes. A processing unit reads and processes the signals from the probes to calculate the thickness of the plate and to warn of potential leakage problems caused by corrosion of the plate. The system can be operated from a remote location outside the oil storage tanks, which minimizes the time and expense in monitoring the plate.

Abstract: An ultrasonic transducer for measuring a property of a material within a defined space has a function of a velocity at which ultrasonic signals travel through the defined space includes a controller. The controller is adapted for coupling to a plurality of ultrasonic transducers. The controller include a multiplexer for selecting one of the plurality of ultrasonic transducers, signal processing means for processing an output of the selected ultrasonic transducer and controller means for providing parameters to the signal processing means based upon the selected ultrasonic transducer. The controller couples to a two wire 4-20 mA communication loop. The controller periodically excites the ultrasonic transducer to obtain a measurement. The controller stores power received from the two wire communication loop and excites the transducer using stored power. The controller is capable of providing power which exceeds that available directly from the two wire communication loop for a brief period of time.

Abstract: An ultrasonic flaw detection device including a transmitting ultrasonic transducer for producing multiple shear wave skips between inner and outer surfaces of a test object, a plurality of receiving transducers positioned ahead of and parallel to at generally the same incident angle as the transmitting ultrasonic transducer, and a processor electrically connected to the receiving transducers so as to produce a humanly perceivable indication of the reflected energy. The receiving transducers serve to receive energy of the shear wave as reflected from discontinuities in the object. Each of the receiving transducers is electronically isolated from the other receiving transducers. The receiving transducers are connected to a single channel of the processor. A fixture is provided having a first opening for detachably receiving the transmitting ultrasonic transducer and a plurality of receiving openers receiving the receiving transducers therein.

Abstract: A method for internal inspection of pieces having an interface with a propagation medium, is described. The steps include: illuminating a reference piece with an ultrasound beam from a first array of transducers excited by stored excitation signals; sensing reflected echo signals received by transducers, which may be the transducers of the first array, and storing the waveforms and time distribution thereof; simultaneously sensing refracted signals, received by transducers belonging to a second array placed opposite to the the first relative to the piece and storing the waveforms and time distribution of the signals received by the transducers of the second array; replacing the reference piece with a piece to be inspected having the same shape and occupying the same location, and applying, to each of the transducers, energization signals obtained by time reversal of the stored waveforms and time distribution; and sensing the signals received by the transducers of the second network.

Abstract: Apparatus for determining, through an interposed medium, the mechanical properties of a solid comprised of more than one material, the solid having a surface.

Abstract: An ultrasonic fixture assembly for holding multiple ultrasonic transducers includes a mounting support rod for attaching the fixture assembly to a manipulator of a ultrasonic inspection system. A plurality of transducer mounting blocks may be mounted to the support rod by an elongated mounting bar or a single transverse mounting block may be mounted to the support rod. Each of the transducer mounting blocks will have a channel formed therein for slidably receiving an ultrasonic transducer or if a single transverse mounting block is used a plurality of channels will be formed through the mounting block. A central channel or a central transducer mounting block is provided for receiving and retaining a longitudinal wave type ultrasonic transducer and other channels or transducer mounting blocks disposed on either side of the longitudinal transducer are formed to hold shearwave type transducers.

Abstract: Columns, walls and other solid structures of concrete, wood, masonry or other materials are non-destructively tested by acoustic signals transmitted from a carriage. The carriage has a frame which is wheel mounted to move over the surface of the test candidate. An internally-mounted piezoelectric crystal roller as an acoustic signal generator or receiver is suspended from the carriage with two degrees of spring freedom to allow accommodation of irregularities in the test candidate surface. The assembly including the piezoelectric crystal roller and its flexible mounting are configured as a replaceable module relative to the carriage frame. The same carriage is useable as an echo type acoustic scanner or, in combination with other devices or carriages, as either an acoustic transmitter or receiver although inclusion of elements to perform both functions within the same carriage is contemplated.

Abstract: A parallel plate transmission line (20) is formed by conformal application of one or more dielectric and conductive layers to the surface under test (70). A signal generator (42) is employed to transmit variable frequency signals (60) along the transmission line (20). Discontinuities in the transmission line (20) cause reflections (62) which are received by a receiver (48). A processor (44) coupled to the signal generator (42) and receiver (48) detects and locates the discontinuities.

Abstract: In a blown film extrusion system in which film is extruded as a tube from an annular die and then pulled along a predetermined path, an apparatus is provided for gauging and controlling the circumference of the extruded film tube. At least one transducer, preferably ultrasonic, is mounted adjacent the extruded film tube for transmitting and receiving interrogating pulses along paths normal to the extruded film tube, and for producing a current position signal corresponding to the circumference of the extruded film tube. The current position signal is continuously compared with at least one previous position signal, preferably with a computer program resident in a controller memory. If at least one preselected condition is violated, the current position signal is disregarded in favor of an estimated position signal.

Abstract: A plurality of probes having image pickup elements differing from each other in image pickup system from each other are used to display an image image-picked-up on a monitor, and a connector of the used image pickup probe is connected to an exclusive adaptor, whereby a drive adapted for the image pickup element is applied to subject the image pickup element to preprocess processing suited for an output signal outputted from the image pickup element. The adaptor is mounted on a signal processing apparatus body, whereby substantially common process processing is subjected to a signal after the preprocess processing by the signal processing apparatus body, to generate a standard image signal. Thus, the standard image signal is displayed on a monitor.

Abstract: In a process for ultrasonic testing of elongated, prism-shaped sections (22) with at least one planar outer surface (54) extending along the longitudinal axis (26) of the section, with the objective of detecting material defects or verifying geometric data, the section (22) to be tested is exposed to ultrasonic beams from several ultrasonic probes (28 to 34) installed in a probe carrier (44). The section (22) is moved along its longitudinal axis (26) in relation to the probe carrier (44). The latter is installed in the rotor (20) of a rotary testing machine which rotates around the longitudinal axis (26) of the section (22).

Abstract: In an ultrasonic inspection system for inspecting the surface condition of an object or the existence or absence of internal defects in it by ultrasonically scanning the object with ultrasonic beams, which have been successively produced as a result of successive excitation of a number of array element oscillators (10.sub.1 -10.sub.n) arranged in a row, and then analyzing waves reflected by the object, reference data for individual ultrasonic beams (individual channels) are collected by ultrasonically scanning a reference material of defect-free uniform quality before ultrasonic inspection of the object. Correction values are prepared based on these reference data, and signals received by the ultrasonic scanning of the object are corrected by these correction values. According to one correction means, the ratios of the average value of reference values of the individual channels to the reference values of the individual channels are determined channel by channel.

Abstract: A non-destructive, non-invasive arrangement is provided for detecting defects, such as voids, or poorly adhering layers in solid objects and laminated materials. A sensing signal is emitted by one transducer and received by two others. All of the sensors are disposed in a housing unit. The difference between the received signals is used to indicate a defect in the work piece proximate one of the transducers.

Abstract: An especially designed probe carries preferably five transducers for the examination of a right circular cylinder flooded with water having limited vertical clearance from the point of required non destructive inspection. The probe includes a generally disc shaped body having a minimal vertical dimension and a radius slightly less than the radius of the right circular cylinder to be inspected. Insertion of the probe interior of the right circular cylinder occurs. At the periphery of the disc, there are disposed five interrogating acoustical transducers. These transducers are spaced from preselected staggered circumferential locations with respect to the right circular cylinder for examination of the water flooded cylinder with refracted rays.

Abstract: An ultrasound imager supports several ultrasonic transducers simultaneously. The imager polls the transducer connection ports to determine which transducers are connected to which port and displays attributes of each transducer in conjunction with a port identification on the screen. The user selects which transducer is to be driven using a trackball or cursor arrow which directs an indicator to point to the selected transducer.

Abstract: A tube inspection station includes a receptacle having walls defining a cavity for holding energy coupling liquid and receiving an object to be inspected in the liquid. At least one wall of the receptacle has a longitudinal bore defined and extending therein from an opening at the top thereof above the cavity and a transverse bore extending through the wall. The transverse bore intersects with the longitudinal bore and opens at both interior and exterior surfaces of the wall. The station also includes a transducer for measuring a parameter of the object, and a mounting assembly removably mounted in the longitudinal and transverse bores of the wall and removably mounting the transducer in the transverse bore such that the first end of the transducer communicates with the cavity and a second end of the transducer communicates with the exterior of the receptacle.

Abstract: An ultrasonic inspection apparatus is adapted for utilizing both pitch/catch and pulse/echo information obtained utilizing a single mode of wave propagation. The apparatus includes an ultrasonic signal transmitting assembly, a signal receiving assembly, a positioning mechanism, and an arrangement for recording the information received by the signal receiving assembly. The transmitting assembly includes at least one source transducer for transmitting shear mode ultrasonic search signals into the mass of an object to be inspected. The signal receiving assembly receives shear mode ultrasonic catch signals that are produced as the ultrasonic search signals encounter discontinuities in the mass of the object to be inspected and are directed toward and detected by at least one catch transducer. The signal receiving assembly also receives shear mode ultrasonic echo signals that are directed back to a first source transducer.

Abstract: An ultrasonic tube inspection system is capable of rapid changeover for inspecting tubes of different diameters for flaws of different orientations. The inspection system includes a serial arrangement of multiple separate inspection stations and a plurality of tube inspecting transducer assemblies supported at each inspection station in a predetermined configuration corresponding to the diameter size of the particular tube to be inspected at the respective inspection station without the need for readjustment.

Abstract: An ultrasonic search system comprises a hollow nozzle block including a plurality of radial nozzle openings, and a probe holder disposed in coaxial relation to the nozzle block and cooperating with the nozzle block to define an annular passage therebetween. A plurality of probes are mounted within the probe holder in radial alignment with the nozzle openings and extend radially from the inner surface of the probe holder toward the nozzle openings, respectively. Water is supplied to the annular passage and injected from the nozzle openings to a test piece of a circular section such as a steel pipe. The test piece passes through the hollow nozzle block while the nozzle block and the probe holder are rotated by an electric motor. Ultrasonic waves are transmitted from the probes through the nozzle openings into the test piece so as to detect flaws in the test piece by reflections.

Abstract: An ultrasonic probe for ultrasonically testing screws includes an ultrasonic transducer array having a plurality of ultrasonic transducers. The ultrasonic transducers selectively operate as transmitters and receivers. Coupling bodies of solid material are each acoustically coupled to a respective one of the ultrasonic transducers. Each of the coupling bodies have a free coupling surface facing away from the respective ultrasonic transducer. The coupling surfaces are adapted to the shape of the surface of a head of a screw to be tested. The coupling surfaces are centered on the head of the screw. A method for operating an ultrasonic probe includes placing and centering the coupling surfaces on the surface of the head of the screw. Different ultrasonic transducers are operated in at least one of transmission and reception modes in each of a plurality of measuring steps, for locating and characterizing a flaw in the material of the screw.

Abstract: In a blow film extrusion system in which film is extruded as a tube from an annular die and then pulled along a predetermined path, an apparatus is provided for gauging and controlling the circumference of the extruded film tube. At least one transducer, preferably ultrasonic, is mounted adjacent the extruded film tube for transmitting and receiving interrogating pulses along paths normal to the extruded film tube, and for producing a current position signal corresponding to the circumference of the extruded film tube. The current position signal is continuously compared with at least one previous position signal, preferably with a computer program resident in a controller memory. If at least one preselected condition is violated, the current position signal is disregarded in favor of an estimated position signal.

Abstract: An ultrasonic tube inspection system capable of rapid changeover for inspecting tubes of different diameter sizes includes a serial arrangement of multiple separate inspection stations. One inspection station is used to inspect for tube dimensions irrespective of the tube diameter size. The other inspection stations are used to inspect for flaws and are employed for different ones of the tube diameter sizes to be inspected. A set of ultrasonic transducer assemblies is supported at each inspection station. The transducer assemblies at the flaw inspection stations are in proper orientations corresponding to the diameter sizes of the particular tubes to be inspected at the respective inspection stations without the need for readjustment. The inspection stations contain quantities of liquid for coupling ultrasonic energy between the ultrasonic transducer assemblies and the tube passing through the inspection stations.

Abstract: A tube inspection station includes a receptacle having walls defining a cavity for holding energy coupling liquid and receiving an object to be inspected in the liquid. At least one wall of the receptacle has a longitudinal bore defined and extending therein from an opening at the top thereof above the cavity and a transverse bore extending through the wall. The transverse bore intersects with the longitudinal bore and opens at both interior and exterior surfaces of the wall. The station also includes a transducer operable for sending waves of energy from its first end into the cavity toward the object and receiving echos of energy at the first end from the object for measuring a parameter of the object. Also, the transducer is operable for transmitting input and output signals at its second end.

Abstract: An ultrasonic diagnostic apparatus comprises at least one piezoelectric transducer which is moved in a scanning process. A first transmission signal and a second transmission signal are different from each other. One of the first and second transmission signals is selectively applied to the transducer. The transducer converts the applied one of the first and second transmission signals into a beam of corresponding ultrasonic wave. The transducer emits the ultrasonic wave beam toward an examined body and receives an echo of the ultrasonic wave beam from the examined body. The transducer converts the received echo into a corresponding received signal. A first signal processor and a second signal processor have different characteristics. The received signal is selectively applied to one of the first and second signal processors to be processed thereby. A sectional image of the examined body is generated on the basis of an output signal from one of the first and second signal processors.

Abstract: So as to control parts of any form, such as panels made of a composite material, a control head (10) is used comprising a small bar made of an elastic material, aligned ultrasonic transducers (18) being placed in said control head which functions by reflected light. The small bar bears contact blocks (22,24) which are brought into support on the surface of the part to be controlled, which has the effect of deforming the small bar and orientating each of the transducers perpendicular to the surface. As regards parts having a non-uniform shape, a uniform quality of the control is thus ensured, the same applying for a reduction of the control time. A precise control of the evolution of the structure of parts during production is also rendered possible. Advantageously, the transducers are mounted on the small bar so as to be disassembled, said mounting being effected by means of wedging members, such as screws and metal wire clips.

Abstract: A ultrasonic device for non-destructive testing of thin tubes, for instance heat exchanger tubes, comprises a head having a longitudinal axis and insertable into a tube. A mechanism imparts to the head a rectilinear motion along and a rotational motion about the axis. The head contains ultrasonic transducers coupled with the tube through a fluid and able to transmit an ultrasonic beam in the form of volume waves in a direction at an angle with the longitudinal axis and to detect echoes. The transducers include one (or more) ultrasonic transducer delivering a focussed beam directed in a plane containing the longitudinal axis and at an angle with a direction perpendicular to the longitudinal axis, and one (or more) second ultrasonic transducer delivering a focussed beam parallel to a line perpendicular to the longitudinal axis and located at a distance from the line. Circumferential as well as longitudinal flaws may consequently be detected.

Abstract: An ultrasonic diagnostic apparatus which has a probe including a plurality of transducer elements made of an electrostrictive material arranged on a plane in two-dimensional directions, a bias applying unit for selecting the transducer elements in an arbitrary row in the horizontal direction to be in an operative condition by applying the same with a bias voltage, and a switching unit for selecting the transducer elements in at least one arbitrary column in the vertical direction by applying the same with a bias voltage, and controls the bias voltage applying unit and the switching unit to scan an ultrasonic beam in the two-dimensional directions to collect three-dimensional information on a body under inspection.

Abstract: An acoustin transducer system for a borehole televiewing apparatus is set forth. In the preferred embodiment, a ceramic circular disc is used and is divided by grooves selected thereon into a set of N concentric rings where N is a whole number integer. Each ring has its own associated transmitter and they are fired in a controlled sequence. Each ring operates as a receiver, and they form output signals which are amplified and controlled delay at the respective delay lines, the several output signals are summed. This assures that the illuminated regions of the borehole is in focus and has a greater depth of field. And a method is also described whereby multiple simultaneous electronically formed acoustic beams are utilized in a differential mode to achieve high spatial resolution in time of flight measurements.

Abstract: A method and system determines the density of a liquid, such as aircraft fuel, by measuring the amplitude of the reflections of ultrasonic pulses from the faces of the walls of a reference material. A transducer is used to transmit an ultrasonic interrogation pulse through a liquid to the reference material. The density of the reference material is known, and its boundaries are well defined. The interrogation pulse is reflected from the faces of the reference material boundaries to provide first, second and third return pulses that can be used to determine the density of the liquid. The density determination is accomplished by determining characteristic impedances, reflection coefficients and transmission coefficients as a function of the returned pulse amplitudes.

Abstract: A sensor comprising a deformable medium, such as rubber, an ultrasonic transducer for transmitting a signal through the medium to a face of the medium and for sensing an echo of the signal returned from the face through the material to the transducer and circuit means for determining the time differential between transmission of the signal and return of the echo and for converting the time signal into a distance measurement.

Abstract: Apparatus for calculating the delay coefficients to be used for the transducer of a linear array at successive focal points along each radial line of a sector along which ultrasonic pulses are transmitted comprising a plurality of clocked accumulators connected in series, the accumulators being preloaded with appropriate combination of the coefficients of the successive terms of a series expressing an approximation of the formula, D=R-.sqroot.(X-Xo).sup.2 +Yo.sup.2 where R is the distance of a focal point from a given point in the sector, X is the number of the accumulator from the origin and Xo, Yo are the coordinates of the focal point.

Abstract: An electronic signal processing device which forms a compound image for any pulse-echo ultrasound imaging system using a two-dimensional array transducer. The processing device obtains the detected sum of a series of cross-shaped apertures within the transducer in order to form a spatial compound image with the output of each cross-shaped aperture consisting of the product of the output signals from the orthogonal arms of the cross.

Abstract: A device for measuring and remotely checking external dimensions of an external lateral face of a part of a work piece. The device comprises measuring means for measuring the length of the part and including a set of two ultrasonic transducers arranged to transmit and receive ultrasound pulses, a movable support for supporting the transducers, abutting means, first rotation means for rotating the supporting means about an axis parallel to the longitudinal axis of the workpiece, and second rotation means for rotating the supporting means between an initial position where the two transducers are substantially directed along a line perpendicular to the longitudinal axis of the workpiece and two predetermined angular positions symmetrical with respect to the initial position, and means for rectilinearly displacing the movable support for bringing the movable support into and out abutting contact with the lateral face to be measured.

Abstract: A method for ultrasonically detecting flaws in a welded portion of a pipe by using an ultrasonic wave phased array probe having an array of a plurality of transducer elements for emitting and receiving ultrasonic wave beams, wherein at least one monitoring probe is located in the vicinity of the welded portion to receive the ultrasonic wave beam, whereby peak values of the ultrasonic wave beams are detected within a predetermined gate, a maximum peak value of the detected peak values is determined to determine a pilot beam having the maximum peak value, and effective beams which reach the portion of the welding portion to be tested are determined from the determined pilot beam.

Abstract: An improved matrix switch circuit comprising an array of analog switches disposed in the form of a matrix and one or more control memories for storing control signals which cause their respective switches of the array to open or close. An interface is provided between the control memories and the array of the switches. The interface receives the control signals from the control memories and holds them. The held signals are then supplied to the switches of the array. While the switches of the array are being controlled according to the control signals held in the interface, the contents of the control memories can be changed at any desired instant.

Abstract: Ultrasonic apparatus and methods for detecting defects in a part include a plurality of transducer channels, at least one of which is dedicated to determining the thickness of the part. An initial thickness value is determined and stored, and then subsequent thickness estimates are compared to the original thickness value and, if the estimates bear a predetermined relationship with the stored thickness value, then the thickness estimates become the new thickness values.