Abstract: An improved plunger for fluid dispensing cartridges used in automated dispensing systems. The plunger helps control the reflection of ultrasonic signals used to sense the position of the plunger as it moves within the cartridge tube. The plunger has a convex bottom, ink-facing surface and a top surface comprising one or more flat, horizontal surfaces. In the preferred embodiment, the horizontal surfaces are concentric steps.

Abstract: A method for ultrasonically inspecting a tubular member, the tubular member having an inner surface, an outer surface, and two spaced-apart ends including a first end of the tubular member, the method including transmitting sonic beams to the tubular member with transducers such that sonic beams are reflected from: the first end and the inner and outer surface of the tubular member, completing inspection of the outer surface of the tubular member while continuing to inspect the inner surface of the tubular member, and sensing a distance from the transducers to the first end of the tubular member, continuing to transmit sonic beams for the inspection of the inner surface of the tubular member until the transducers are near its first end; and, in one aspect, detecting an inner surface defect near the first end of the tubular member after the outer surface inspection has ceased.

Abstract: A method for sizing crack is disclosed using a combination of depth crack sizing methods to improve crack sizing accuracy for thin walled tubing and tight crack surface opening less than 0.001 inches for cracks of any depth. The tube or plate wall can consist of a single material or multiple metallic electrodeposited or otherwise intimately bonded layers of materials with different magnetic properties and the sizing method comprises known depth sizing methods such as shear wave, time of flight and THE SELECTIVE USE OF two unique depth sizing methods designated as Mode Converted Signal (MCS) and Full Skip Normalization (FSN) which provide correction factors for the known sizing methods.

Abstract: A mixer shifts the center frequency of a received signal to a baseband according to a center frequency detected by a center frequency detector or a center frequency estimated from ship speed, for example, by a center frequency estimator. The passband of a variable passband filter varies according to a bandwidth detected directly from the received signal by a bandwidth detector or a bandwidth estimated from the pulselength of a transmitting signal by a bandwidth estimator, whereby the bandwidth of a baseband signal output from the mixer is limited to remove undesired noise components in the received signal.

Abstract: An ultrasonic image process and system for accurately evaluating the quality of a weld using ultrasonic responses and operator entered data to enhance the quality of weld inspection. Ultrasonic responses useful in accurately indicating the actual location of the weldment, detecting the actual component thickness and the location and characteristic of any other relevant ultrasonic reflectors located in or near the weld heat effected zone are input to a composite image of a weldment for the purpose of enhancing the quality and the ease of detecting, evaluating and sizing of weld defects. Through the superposition of ultrasonic image data from additional complimentary sensors and operator inputs based on prior known data, useful images can be formed to improve the decision making in weldment inspection and evaluation.

Abstract: A method for ultrasonically inspecting a tubular member, the tubular member having a first surface, a second surface, the first surface spaced apart from the second surface by a thickness of the tubular member, and two spaced-apart ends including a first end of the tubular member, the method including transmitting sonic beams to the tubular member with transducer apparatus such that sonic beams are reflected from the first surface of the tubular member and from the second surface of the tubular member, the transducer apparatus controlled by control apparatus, while continuing to inspect the first surface of the tubular member for first surface defects, moving the transducer apparatus adjacent sensing apparatus which signals the control apparatus to cease processing of transducer apparatus signals related to inspection of the second surface, and, the transducer apparatus continuing to transmit sonic beams for the inspection of the first surface of the tubular member, and completing inspection of substantially

Abstract: A method of detecting the presence or absence of a blockage in an enclosed environment is provided. The method includes introducing an acoustic wave into the enclosed environment; receiving at sensor locations the acoustic wave and any reflected acoustic wave caused by the acoustic wave contacting a blockage; and, analyzing the acoustic wave and any reflected acoustic wave to determine the presence or absence of the blockage. The method can also include coherently accumulating into a digitized data array an electrical response indicative of the received acoustic wave and any reflected acoustic wave caused by the blockage. The method can further include computing a correlation between the introduced acoustic wave and the digitized data array. A system is also disclosed for detecting the presence or absence of a blockage in an enclosed environment. The system can include a communications interface for remote analysis and/or control of the system by a user.

Abstract: A method for ultrasonically inspecting a tubular member, the tubular member having an inner surface, an outer surface, and two spaced-apart ends including a first end of the tubular member, the method including transmitting sonic beams to the tubular member with transducers such that sonic beams are reflected from: the first end and the inner and outer surface of the tubular member, completing inspection of the outer surface of the tubular member while continuing to inspect the inner surface of the tubular member, and sensing a distance from the transducers to the first end of the tubular member, continuing to transmit sonic beams for the inspection of the inner surface of the tubular member until the transducers are near its first end; and, in one aspect, detecting an inner surface defect near the first end of the tubular member after the outer surface inspection has ceased.

Abstract: A method and apparatus for analyzing a deposited layer on the inner surface of a fluid container wall having inner and outer surfaces are disclosed. One embodiment of the method comprises (a) transmitting an acoustic signal from a transmitter at a first distance from the outer surface of the wall; (b) receiving a first received signal A, comprising a reflection from the wall outer surface; (c) receiving a second received signal B, comprising a reflection from the wall inner surface; (d) receiving a third received signal C from the wall inner surface; (e) calculating a coefficient Rwp from A, B and C, and (f) calculating a coefficient Rpd from A, B and Rwp and calculating the acoustic impedance of the deposited layer Zd from Rwp, Rpd, and Zw, where Zw is the acoustic impedance of the material between the transmitter and the wall outer surface.

Abstract: A two-dimensional sensor array for high throughput screening of fluids in micro-machined fluid arrays is provided. The sensor array includes a two-dimensional array of piezoelectric transducers which are in contact with the back-side of the micro-machined fluid array which is opposite from the fluid positions. A means is provided to generate and detect shear or longitudinal ultrasonic waves in a time-multiplexed manner whereby the waves could propagate in either a pulse or continuous mode. A means to determine fluid parameters based on the shear and longitudinal ultrasonic waves is also provided. Furthermore, a fluid dispense system could be included which is then controlled based on the determined fluid parameters and a feedback control system. The two-dimensional micro-sensor array is compatible with and based on miniaturization technologies for high-throughput biology, such as micro-fluidics, detection, sample handling, and bioassay technology amenable to high-density formats.

Abstract: A method for determining a remaining service life of switching contacts in an electric switching device. The method includes operating the switching contacts so as to produce structure-borne sound signals, capturing the structure-borne sound signals, performing a Fourier transform on the structure-borne sound signals in a plurality of discrete time windows so as to produce a sonogram, determining a plurality of function values using the sonogram, and evaluating the plurality of function values using an evaluation device. Also a electrical switching device including first and second switching contacts, a sound sensor configured to capture structure-borne sound signals produced by an operation of the first and second switching contacts, and an evaluation device configured to evaluate the first structure-borne signals so as to determine a remaining service life of the first and second switching contacts.

Abstract: A system includes a switching device, a sound device and an evaluation device. The switching device includes a housing and a contact system disposed in the housing, the contact system including a contact piece carrier and a contact piece disposed on the contact piece carrier. The sound device produces and captures structure-borne sound waves so as to determine an equivalent criterion for determining the remaining service life of the contact piece. The evaluation device evaluates the equivalent criterion.

Abstract: A method for inspecting a clad pipe, having the steps of: transmitting longitudinal ultrasonic waves with wide-band characteristic to make it incident on an inner surface of a clad pipe, the clad pipe including a metal pipe with a coarse crystal grain structure and a different kind of clad metal built up on an inner surface thereof; and receiving reflected echoes of the longitudinal ultrasonic waves on the inner surface side thereof. When a flaw generated in an interface between the metal pipe and the different kind of metal is to be detected, the longitudinal ultrasonic waves in a frequency range of 10 to 30 MHz are preferably used as the ultrasonic waves. When the pipe thickness of the clad pipe is to be measured, the longitudinal ultrasonic waves in a frequency range of 2 to 10 MHz are preferably used as the ultrasonic waves.

Abstract: A method and apparatus is proposed for judging the friction behavior between two counter-running partners, each of which has a contact surface, with the one contact surface moving along the other contact surface in the operating state. One of the contact surfaces is charged with ultrasonic signals (UI; UW), ultrasonic signals which are reflected by the contact surface are received as echo signals (ES), the echo signals (ES) are supplied to an evaluation unit as received signals, the Doppler shift of the received signals is determined by means of the evaluation unit, and the friction behavior between the counter-running partners is judged by means of the Doppler shift.

Abstract: A method of correcting for phasefront aberrations in ultrasound imaging uses highly spaced apart point scatterers artificially placed in the tissue being imaged. The point scatterers reflect the transmitted sound and are individually differentiated to provide singular reference points for correction of signals reflected from the surrounding tissue. The differentiation is performed by comparison of the third or fourth harmonic frequencies of the reflected signals. To ensure the necessary high dispersal of the point scatterers, high amplitude pulses of the transmitted signal destroy point scatterers in selected image regions. In an alternate embodiment, correction is performed by stochastic analysis of signals reflected from the highly dispersed point scatterers. A reference signal is compared to the second harmonic of the reflected signal to reduce noise.

Abstract: A ultrasonic transceiver includes a case for housing a ultrasonic sensor having a transducer provided therein, and a resilient member to be interposed between the case and an ultrasonic sensor. The surface of the case opposing the side surface of the ultrasonic sensor is tapered with respect to the surface of the ultrasonic sensor without involvement of the resilient member.

Abstract: The invention relates to a method for non-destructive testing of materials, in which at least two differently guided waves (modes) are produced in the solid body, each at at least one specified angle, the measured reflection values are placed in relation to a reference echo in order to obtain a relative reflection value, and the relative reflection values of the individual modes are again placed in relation to one another, thereby enabling the size and type of the defects to be determined.

Abstract: Described is a method for a coarse differentiation between a liquid and a bulk material of a filling material present in a receptacle using a filling level measuring device that scans a reflected echo signal. The coarse differentiation is made in dependence on the width of the individual echoes of an envelope curve in an echo signal. Alternatively, the coarse differentiation may also be made in dependence on the number of equidistant echoes in an echo signal, or in dependence on the detection of a stirring apparatus. All these alternatives may also be combined with each other. Also described are devices and filling level measuring devices configured for the realization of the methods.

Abstract: An end effector for supporting an ultrasonic testing probe on a robot arm having a robot mounting bracket for use in a nuclear reactor pressure vessel. The end effector has a wrist assembly with a rotatable wrist axle. The wrist assembly is coupled to the robot mounting bracket and a probe assembly is coupled to the wrist shaft. The ultrasonic testing probe is floatably disposed within the probe assembly.

Abstract: An ultrasonic monitoring method and system is disclosed. The method includes transmitting a sequence of ultrasonic pulses into a space; receiving a resultant echo signal; monitoring the space for intrusion by comparing the resultant echo signal received in a first window period with the resultant echo signal received in a second window period, wherein the pulses within the sequence are separated by a time interval such that echoes generated from the pulses are superimposed to form the resultant signal.

Abstract: A detector equipped with force feedback for detecting detonatable devices such as land mines is disclosed. The detector includes a rod having a tip for placing beneath the surface of the ground and for contacting unknown objects. The tip ultrasonically provides an indication of the presence of a metal or plastic material. Another rod within the device is used to compensate the device during use against unknown pressures applied to the rod beneath the surface of the ground.

Abstract: An ultrasonic testing method uses surface waves to prevent false detection of primary cracks, to lower the level of structural noises from grain boundaries, and to improve the detectability in the ultrasonic testing by surface wave testing of hot rolling rolls. A surface wave probe 10 capable of transmitting and receiving a surface wave is provided with a piezoelectric element 10A, a resin wedge 10C disposed on the front surface of the piezoelectric element 10A and a damping block 10B disposed on the back surface. The surface wave probe 10 is driven to produce a short pulse having a pulse length being at most 2.5 times the wavelength of the surface wave to be produced. A coupling liquid medium is supplied to the probe 10 in accordance with the peripheral speed of the roll to be tested. Depending on the height of the reflected waves measured, the grinding allowance of the roll is determined, and the roll is ground according to the thus-determined grinding allowance.

Abstract: A tank 10 has an opening through which enters a molded material P1, which is the object of inspection, and water W1 is filled within the tank 10. One side wall of said tank 10 is equipped with the plurality of ultrasonic search units 40. On the other side wall of said tank 10 is mounted a reflector plate 100 opposing to said ultrasonic search units 40. The reflection surface 100a of said reflector plate 100 is positioned away from the surface of an object portion P10 by a predetermined distance D1. The ultrasonic waves generated from the search units are reflected, and the reflected waves are transduced into electric signals, and the signals are compared with the signals received from the solid portion, so as to detect flaw.

Abstract: A method of ultrasonically testing the disk bore and keyway area of a shrunk-on steam turbine rotor disk or hub is provided. The method employs a one or more scanning ultrasonic phased linear array probes mounted on the disk to inspect the disk bore and keyway area on the opposite side of the disk.

Abstract: In order to detect buried compliant objects such as land mines and pipes, an acoustic signal is directed into the ground to excite vibration of a buried compliant object. A probing signal is also directed into the ground toward the vibrating object, and the probing signal is modulated and reflected by the vibrating object. The modulated, reflected probing signal is processed to determine therefrom the presence of the buried compliant object.

Abstract: A corrosion sensor and method for its use to detect and determine the, type, location, size and growth rate of corrosion of metals and the like in a corrosive environment. The corrosion sensor can distinguish between different types of corrosion such as uniform corrosion, pitting, crevice, and stress corrosion cracking. The sensor detects corrosion conditions of a corrodible metal article in a corrosive environment. It has a metal probe comprised of a metal which is substantially identical to that of the corrodible metal article and a transducer element attached to said probe, which is capable of projecting and receiving ultrasonic or radio frequency signals through the probe. The received signals indicate corrosion of the probe and hence the corrodible metal article.

Abstract: An ultrasonic inspection method for determining acceptability of material for microstructurally sensitive applications comprises providing a material, directing ultrasonic energy of ultrasonic inspection to the material; scattering reflected energy in the material; determining an amount of noise generated by the ultrasonic inspection; and characterizing the material as acceptable if the amount of noise corresponds to a pre-determined noise level. The invention also sets forth a system for implementing the method, as embodied by the invention.

Abstract: An ultrasonic ice detector that can be mounted directly to the skin of an aircraft includes a transducer that is coupled to the interior surface of the skin, and transmits acoustic vibrational energy through the skin. A reflector bar having a reflector surface is mounted on the interior surface of the skin at a location spaced from the transducer and is effective to reflect acoustic energy back to the transducer. The reflector bar is raised from the interior surface and preferably has a width equal to the width of the acoustic wave that is generated by the transducer at the reflector location. The transducer and reflector are non-intrusive and do not alter the aircraft skin structural integrity. The arrangement provides an accurate, responsive sensor for determining presence of ice or other contaminants on the exterior surface of the skin.

Abstract: An air spring system for a motor vehicle includes essentially a flexible member (4) having first and second ends. At a first end, the flexible member is closed off by the cover plate (8) as a connecting part and, at its second end, by a roll-off piston (10) as a second connecting part. To carry out a contactless distance measurement in accordance with the pulse/echo method in the interior space (6) of the air spring (2), an ultrasonic transmitter/receiver (14) is mounted on one of the two connecting parts (8, 10) and a reflector (16) is provided on the other one of the two connecting parts (8, 10). A separate reference reflector (18) is not used in order to simplify the construction and to save mounting space for the components. Instead, the reflector is configured as a two-step reflector. The one step functions as a target reflector (16) and the other step (26) functions as a reference reflector. A bumper (28) is preferably configured as a two-step target reflector (16).

Abstract: A system and a method are provided for monitoring the condition of an interface. Although not limited to this particular application, the system and method are particularly suited for monitoring the interface of two liquid lubricated mechanical seal faces. The system monitors an interface by using a wave source to produce an ultrasonic shear wave, directing the wave at the interface, detecting the wave after it interacts with the interface, and comparing the detected wave to predetermined wave characteristics. Based on the comparison, an alarm may be triggered. The alarm may indicate that the mechanical seal is failing.

Abstract: An ultrasonic test process and device intended for testing a preferably cylindrical specimen (2), such as railway wheel, which is capable of displacement along a support, such as a rail (10). The ultrasonic test device comprises at least one ultrasonic probe (14) disposed in the support (10) which emits acoustic waves in the direction of the specimen. The acoustic waves are reflected by defects in the specimen (2) and received again by a probe. The test device is designed to reliably and non-destructively test the volume and surface of the specimen (2) as it rolls over the support (10). In the process of the invention a number (m) of probes (14) are controlled so that the ultrasonic waves have a preferably horizontal polarization and are emitted into the specimen (2) at a predetermined angle (66) relative to the running surface (8) of the rail (10).

Abstract: An ultrasonic testing method uses surface waves to prevent false detection of primary cracks, to lower the level of structural noises from grain boundaries, and to improve the detectability in the ultrasonic testing by surface wave testing of hot rolling rolls. A surface wave probe 10 capable of transmitting and receiving a surface wave is provided with a piezoelectric element 10A, a resin wedge 10C disposed on the front surface of the piezoelectric element 10A and a damping block 10B disposed on the back surface. The surface wave probe 10 is driven to produce a short pulse having a pulse length being at most 2.5 times the wavelength of the surface wave to be produced. A coupling liquid medium is supplied to the probe 10 in accordance with the peripheral speed of the roll to be tested. Depending on the height of the reflected waves measured, the grinding allowance of the roll is determined, and the roll is ground according to the thus-determined grinding allowance.

Abstract: An ultrasonic ice detector that can be mounted directly to the skin of an aircraft includes a transducer that is coupled to the interior surface of the skin, and transmits acoustic vibrational energy through the skin. A reflector bar having a reflector surface is mounted on the interior surface of the skin at a location spaced from the transducer and is effective to reflect acoustic energy back to the transducer. The reflector bar is raised from the interior surface and preferably has a width equal to the width of the acoustic wave that is generated by the transducer at the reflector location. The transducer and reflector are non-intrusive and do not alter the aircraft skin structural integrity. The arrangement provides an accurate, responsive sensor for determining presence of ice or other contaminants on the exterior surface of the skin.

Abstract: A method for evaluating bonding properties of a metallic pipe, the method comprises steps of measuring, in advance of a pipe expansion operation, at least one selected from a degree of shape discontinuity, a degree of defect at a bonding portion, and a degree of change in crystal structure, and comparing a measurement value with a predetermined threshold value to evaluate suitability of the bonding properties for applying pipe expansion.

Abstract: A process and device are disclosed for recognizing foreign bodies in viscous or fluid masses with lumpy foodstuffs. The mass to be checked runs through a measurement section, in which, pulsed ultrasonic signals are emitted through the mass, are reflected after passing through the mass, and after passing again through the mass they are received and compared with the ultrasonic echo of the reflection surface. When the changes of the received signals exceed a predetermined threshold value, a warning or actuating signal is generated to interrupt mass advance. The parameters to be evaluated for the signal may be their amplitudes, as well as the speed of change of their amplitudes or the propagation times.

Abstract: Apparatus for detecting an interface (13) between two media of a heterogeneous system, comprising transmission means (21) to send a signal through one medium from the transmission means (21) to the interface (13), measuring means (32b, 32c, 32d) to measure the time taken for the signal to be reflected to a reception means (36), and processing means (40c, 40d) to use said time to determine the distance of the interface from the transmission means.

Abstract: A probe 10 transmits an ultrasonic pulse of a wide band, and detects its echo to generate a reception signal. The reception signals are respectively filtered by three filter parts (14a to 14c) of different passing bands. Outputs of the respective filter parts (14a to 14c) are signal components of a narrow band, and speckle components (interference components by a fine structure) appear conspicuously. Outputs of the respective filter parts (14a to 14c) are detected, and the detection outputs are set respectively as each color signal of R, G and B, and are composed by an image composition part (20), whereby a speckle part is displayed by coloring in R, G or B. As a tissue boundary part is high in a signal level in any band, it is displayed in a whitish color by composition.

Abstract: A method is proposed for judging the friction behavior between two counter-running partners (2, 3), each of which has a contact surface (21, 31), with the one contact surface (31) moving along the other contact surface (21) in the operating state, comprising the following steps: one of the contact surfaces (31) is charged with ultrasonic signals (UI; UW), ultrasonic signals which are reflected by the contact surface (31) are received as echo signals (ES), the echo signals (ES) are supplied to an evaluation unit (6) as received signals, the Doppler shift of the received signals is determined by means of the evaluation unit (6), and the friction behavior between the counter-running partners (2, 3) is judged by means of the Doppler shift.

Abstract: There is provided a monitor and method for monitoring the condition of a photoresist film on a wafer in which the phase of high frequency ultrasonic pulses reflected from the wafer/photoresist interface provides an indication of the condition of the photoresist film.

Abstract: A profile of a rack, that may have zero, one, or a plurality of containers may be obtained using an ultrasonic sensor. The sensor emits a plurality of ultrasonic bursts and the rack is transported under the sensor at a slew speed that allows the sensor to detect at least first and second echoes from each of the bursts. Data points, corresponding to each of the first and second echoes, are generated and the data points are captured in a memory device. The data points, generally reflecting the levels of the rack and any containers, are processed to dynamically and non-invasively (i.e., without physically contacting the liquid with a probe) determine information about the container types, whether any container is capped, and, if one or more containers are uncapped, the liquid level in the uncapped containers.

Abstract: An ultrasonic imaging system including an aberration correction system uses a harmonic component of the fundamental transmitted frequency for imaging, or for aberration correction, or both. By properly selecting the frequency pass bands of filters used in the image signal path and in the aberration correction signal path operating advantages are provided. The aberration correction values may be calculated concurrently with image formation.

Abstract: A method for measuring the height of the cutting table of an earth-processing implement or an agricultural implement, such as, for example, a combine harvester, relative to a surface of a ground having crops by means of an acoustic transducer arrangement. The method includes forming the sound signal emitted by the transducer arrangement by a pseudonoise signal covering a predetermined frequency band. Comparing the sound signal with the reflected signal. Mutually delaying the sound signal and the reflected signal until the comparison has reached its optimum. Whereafter, the delay represents a measurement of the distance to the surface of the ground.

Abstract: A method for inspecting welds uses a single EMAT tranducer operated in pulse-echo mode that sends and receives Rayleigh waves to detect defects in a weld between sheet plates of dissimilar thicknesses.

Abstract: Methods and apparatus enabling the length of a reinforcing geogrid for earthen structures to be determined even when the geogrid is buried. The preferred geogrid body comprises a plurality of spaced apart, elongated spans that are regularly intersected by similar, elongated, transverse spans. Voids defined between intersecting body spans facilitate the attachment of the geogrid to retaining walls, or other wall or earthen structures. A test line, preferably an electrically conducive wire, is molded into the geogrid body. The length of this conductor is electrically calculated and displayed to determine the length of the buried geogrid. Preferably an electrical pulse is generated and applied to the geogrid and a return echo is thereafter detected. The time difference between the pulse application and the return echo is electrically sampled and correlated to the conductor length. In alternative embodiments either sonic or light energy is applied to the test line for measurements.

Abstract: An ultrasonic imaging system including an aberration correction system uses a harmonic component of the fundamental transmitted frequency for imaging, or for aberration correction, or booth. By properly selecting the frequency pass bands, of filters used in the image signal path and in the aberration correction signal path operating advantages are provided. The aberration correction values may be calculated concurrently with image formation.

Abstract: A sample-holding container having a structure that may be heated and internally pressured with water to subject the sample to its anticipated working conditions as the sample is tested. A single, oil-encapsulated transducer transmits acoustic energy waves through a chamber containing the sample and receives reflections of the waves from the chamber floor. The transducer converts the received reflected acoustic waves to an electrical signal that is analyzed to evaluate the sample. Pressurized water in contact with the sample is employed in the chamber to pressurize the sample during the test. A movable, pressure-responsive barrier between the oil encapsulating the transducer and the water pressurizing the sample maintains the transducer and the sample at the same pressure. A thin membrane between the transducer and the sample permits the transducer to be in physical contact with the sample while protecting the transducer from chemical exposure.

Abstract: A system which rapidly determines the elastic stiffness constants of materials in plate shape as well as characterize material flaws that are affecting these constants. Rapid (below a minute) nondestructive evaluation system allow for the determination of material stiffness constants, low noise data acquisition algorithm for measuring spectral data. A real time method of displaying leaky Lamb wave spectral data.

Abstract: To permit immersion ultrasonic testing of a semiconductor processing component manufactured of porous metal, a cover is sealed over the processing surface of the component. The cover creates an acoustically reflective air gap between the cover and the processing surface. Ultrasonic waves scanned across the component reflect from this gap, creating an image of the internal structure of the component.

Abstract: The invention provides a device for the ultrasonic inspection of a multilayer metal workpiece consisting of at least one parent metal layer and a clad metal layer, and having an outer surface, at least one boundary surface, and an inner surface, the device comprising a housing accommodating at least three spaced-apart, ultrasonic transducing means capable of receiving electrical input signals, initiating transmission of ultrasonic waves to the workpiece, and receiving reflected ultrasonic waves to be transduced into electrical output signals, the transducing means being constituted by an acoustic prism having a first face for at least indirectly contacting a workpiece, a second face extending in a plane forming an angle .alpha. with the plane of the outer surface of the workpiece, and a piezocrystal attached to the second face, wherein the distance L.sub.

Abstract: A method for producing objective, verifiable data which discovers and documents hidden prior vehicle paint and body damage by measuring paint with non-destructive instrumentation at several locations on the exterior surface of an automotive vehicle's body panels, comparing the highest and lowest of these measurements with the standard maximum and minimum measurements, and evaluating the vehicles as to the extent and location of repainting or body damage. Another step of calculating the range of the vehicle's measurements, and comparing these measurements and their range to the normal measurement variations found on new or unrepaired vehicles provides more conclusive evidence of repainting. A vehicle is then evaluated as having one or more body panels refinished if the range of measurements is greater than normal acceptable factory variation.