Abstract: Combinations of multiple analytic techniques may be used to identify changes to a structure based on changes in characteristics of acoustic signals traveling along the structure. Acoustic signals traveling along the structure may be monitored to detect changes in characteristics of the acoustic signal from baseline signal characteristics. The changes in characteristics of the acoustic signals may be processed using multiple analytic techniques to provide analyses of the change in time-domain, in frequency-domain, and in mixed time-frequency-domain. The change to the structure may be identified based on a combination of the results of the analysis in time-domain, in frequency-domain, and in mixed time-frequency-domain.

Abstract: A health and condition monitoring system of an elastomeric component comprising an actuator, a sensor, and a processing unit. The sensor and the actuator need to be attached directly or indirectly to the elastomeric component. The actuator induces an impulse, or possibly a chirp, into the elastomeric component. The sensor senses the response, the impulse response function. The processing unit analyzes the impulse response function and determines a health and condition indicator. This is repeated and when enough indicators have been determined, then a health and condition marker can be determined, covering if the elastomeric component is in a start period of usage, in a main usage period or in a final period of usage.

Abstract: A thermal-mechanical testing apparatus for use with an electrically conductive specimen testing system. In one embodiment, the apparatus includes a first compression anvil assembly, a mounting frame coupled to the first compression anvil assembly, and a second compression anvil assembly positioned opposite the first compression anvil assembly and the mounting frame. The first compression anvil assembly includes a mounting plate, a first compression anvil coupled to the mounting plate, and a heating current ground system coupled to the mounting plate. The mounting frame includes a set of conductive end plates, a set of insulating connectors connecting the conductive end plates, and a plurality of mounting components coupled to the insulating connectors. The mounting components are also coupled to the mounting plate.

Abstract: The present invention discloses an MEMS sensor and a method for making the MEMS sensor. The MEMS sensor according to the present invention includes: a substrate including an opening; a suspended structure located above the opening; and an upper structure, a portion of which is at least partially separated from a portion of the suspended structure; wherein the suspended structure and the upper structure are separated from each other by a step including metal etch.

Abstract: An elastography device for quantitatively and/or qualitatively measuring the viscoelastic properties of any medium, includes a deformable tube for positioning the ultrasonic transducer located at the end of the deformable tube and for holding it so as to ensure, during at least one measurement, perpendicularity and contact between the ultrasonic transducer and the medium.

Abstract: The present invention discloses an MEMS sensor and a method for making the MEMS sensor. The MEMS sensor according to the present invention includes: a substrate including an opening; a suspended structure located above the opening; and an upper structure, a portion of which is at least partially separated from a portion of the suspended structure; wherein the suspended structure and the upper structure are separated from each other by a step including metal etch.

Abstract: A method and system for determining contact along a surface of an ultrasound probe are provided. The method includes frequency analyzing ultrasound signals received by the ultrasound probe and displaying indicators of acoustic contact of the ultrasound probe with an object based on the frequency analysis.

Abstract: The present invention provides systems and methods to use a measured driving-point response of a nonlinear material to determine one or more elastic properties of the material. The present invention takes advantage of the full information represented by the transient component, the steady-state component, the anharmonic components, and the nonlinear response components of a measured driving-point response of a real nonlinear material, without limitation in the use of large-amplitude forces. The elastic properties are determined by forming and solving a time-domain system of linear equations representing a differential equation model of the driving-point motions of the material. Based on a single, short duration, large-amplitude driving point measurement, both linear and nonlinear properties can be determined; both large-amplitude and near-zero amplitude properties can be determined; and elastic-wave speed and elastic moduli and their variation with depth can be determined.

Abstract: System and method for automatically measuring the delay of tissue motion and deformation. For example, asynchrony may be measured between the left and right ventricles and within the left ventricle. A measurement feature may be defined by default or obtained using a user input. A reference time and a search interval are identified. The search interval may be based on the reference time, or input or modified by a user. A time delay of the measurement feature within the search interval is calculated for each sample. At least one color is assigned to the samples corresponding to the calculated time delay.

Abstract: A contact force sensor package includes a substrate layer having a vibration detection unit and a pair of first junction pads that are electrical connection ports which are provided on an upper surface of the substrate layer, a flexible circuit substrate layer having a pair of second junction pads provided at a position corresponding to the first junction pads and electrically connected to the first junction pad, a vibration transfer unit having one side contacting the vibration detection unit and the other side contacting a human body and transferring a sphygmus wave of the human body to the vibration detection unit, and an adhesion layer formed between the substrate layer and the flexible circuit substrate layer to reinforce a junction force between the substrate layer and the flexible circuit substrate layer, the adhesion layer being not formed in an area overlapping at least the vibration transfer unit.

Abstract: The present invention provides systems and methods to used a measured driving-point response of a nonlinear material to determined one or more elastic properties of the material. The present invention takes advantage of the full information represented by the transient component, the steady-state component, the anharmonic components, and the nonlinear response components of a measured driving-point response of a real nonlinear material, without limitation in the use of large-amplitude forces. The elastic properties are determined by forming and solving a time-domain system of linear equations representing a differential equation model of the driving-point motions of the material. Based on a single, short duration, large-amplitude driving point measurement, both linear and nonlinear properties can be determined; both large-amplitude and near-zero amplitude properties can be determined; and elastic-wave speed and elastic moduli and their variation with depth can be determined.

Abstract: This invention relates to a device for determining vibration characteristics of vibrated, supported, generally round, substantially ellipsoid articles, such as eggs, comprising: an elastic hammer with handle and head, for tapping and thereby acoustically vibrating such article, a handle drive element for reciprocating the hammer generally in a plane around an axis in the handle, a microphone arranged immediately adjacent to and directed to the article, for picking up acoustic vibrations generated by the article, and a signal processing means for processing the signals picked up by the microphone for determining vibration characteristics of the article, characterized in that the handle adjacent the axis consists of an arm portion to be driven which is connected, through a hinge element, with a handle end having at the extremity thereof a mount having therein a ball as a head, while at least the hinge element and the handle end form a hammer rod in one piece.

Abstract: The present invention provides a portable test system for in-situ, non-destructive identification of visco-elastic material. The system includes a probe-like member coupled to a controller, wherein the controller is responsive to an output signal from the probe-like member for determining properties of the visco-elastic material. The probe-like member includes a longitudinally extending housing. A transducer mechanism is operably positioned within the housing. The transducer mechanism includes an indentation tip member, wherein the indentation tip member is extendable through the housing. A load mechanism is provided for loading the transducer mechanism with a desired constant load, causing the indentation tip member to extend through the housing to perform an indentation. A force calibration mechanism is provided for calibrating the application of a fixed force between the indentation tip member and the visco-elastic material.

Abstract: A method and system for acoustic treatment performance testing in a free-ld acoustic environment is provided. A sound source directs a gated acoustic pulse at an acoustic treatment. Acoustic pressures of the gated acoustic pulse and reflected energy from the acoustic treatment are measured from a location approximately in-line with the source and the acoustic treatment. This measurement location is at least one-half the wavelength of the frequency of interest away from the source and is at least a distance equal to (t*c/2) away from the acoustic treatment where t is equal to the duration of the gated acoustic pulse and c is equal to the speed of sound in the free-field acoustic environment. The acoustic pressures of the gated acoustic pulse and reflected energy are compared as an indication of performance of the acoustic treatment at a frequency of interest.

Abstract: Apparatus for sensing the flexure of a surface includes an array of bistable dome shaped switches within the surface which change their state or position depending on the direction and degree of local flexure of the surface. A flexible sheet parallel to the surface carries wiring for detecting the state of the bistable switches and carrying this information to a computer. A second parallel sheet may be used to detect the second position of the bistable switches for extra accuracy. The bistable switches may be linked, meaning the perimeters of the bistable switches overlap, or unlinked. The two stable positions may include two oppositely protruding positions, or one protruding position and one flat position.

Abstract: Material is periodically indented by a probe driven at an oscillation frency by a shaker regulated by an analyzer to which input measurement data is fed from a sensing head connecting the shaker to the probe for in situ measurement of material resistance to indentation to which such input data relates. A computer connected to the analyzer is programmed to calculate steady-state data on dynamic material properties as a time dependent function, from outputs of the analyzer restricted to limits determined from the input measurement data.

Abstract: A plurality of elongated test specimens undergo vibrations induced by ran noise within an acoustical frequency range establishing standing waves therein having resonant frequencies at which the collection of measurement data through accelerometers mounted at the ends of the specimens provides for calculation of physical material properties. The processing of the data during collection, analysis and calculation is automated by programmed computer control.

Abstract: A plurality of elongated test specimens undergo vibrations induced by ran noise within an acoustical frequency range establishing standing waves therein having resonant frequencies at which the collection of measurement data through accelerometers mounted at the ends of the specimens provides for calculation of physical material properties. The processing of the data during collection, analysis and calculation is automated by programmed computer control.

Abstract: A probe has a vibration excitor including a core member made of a giant magnetostrictive material and magnetic field generation means for generating an alternating magnetic field having a randomly varying frequency to thereby expand and compress the core member to generate random vibration therein, and an impedance head for detecting an acceleration of the random vibration and a vibration stress created in organism tissue vibrated by the vibration excitor and generating electrical signals proportional thereto. A viscoelasticity measurement device using the above probe for the organism tissue is also disclosed.

Abstract: A system for using Doppler modulation parameters for producing an estimation of the vibration amplitude of an object under investigation is disclosed in which a low frequency vibration source is used to force the oscillation of the object under investigation and a coherent or pulsed ultrasound imaging system is utilized to detect the spatial distribution of the vibration amplitude of the object in real-time. The reflected Doppler shifted waveform generated by reflecting the ultrasound waves off of the vibrating object under investigation is used to compute the vibration amplitude and frequency of the object using two alternative methods, either on a frequency domain estimator basis or on a time domain estimator basis. The system may also be utilized for breast imaging and tumor detection.

Abstract: A method and apparatus is provided for dynamic mechanical measurements of materials in which a plurality of coplanar coils are disposed transversely with respect to a magnetic flux field. The coils are rigidly mounted to a plate and arranged so as to eliminate inductive coupling between the coils. Alternating current is passed through some of the coils so as to vibrate or oscillate the plate because of the alternating force resulting from the interaction of the electrical current and the magnetic field. Other of the coils have an alternating motional electromotive force (voltage) generated in them because of their vibration. The mechanical impedance of the plate is determined from the vector ratio of the vibration forcing current to the velocity sensing voltage. When the plate is connected to the material to be tested in vibration, measurements of the vector ratio of electrical current to motional voltage then provide determinations of dynamic mechanical properties at vibration frequencies from 0.

Abstract: A non-invasive system and method for inducing vibrations in a selected element of the human body and detecting the nature of responses for determining mechanical characteristics of the element are provided. The method comprises the steps of: inducing multiple-frequency vibrations, including below 20 KHz, in a selected element of the body by use of a driver; determining parameters of the vibration exerted on the body by the driver; sensing variations of a dimension of the element of the body over time, including in response to the driver; correlating the variations with frequency components of operation of the driver below 20 KHz to determine corresponding frequency components of the variations; resolving the frequency components into components of vibration mode shape; and determining the mechanical characteristics of the element on the basis of the parameters of vibration exerted by the driver and of the components of vibration mode shape.

Abstract: A non-invasive system and method for inducing vibrations in a selected element of the human body and detecting the nature of responses for determining mechanical characteristics of the element are provided. The method comprises the steps of: inducing multiple-frequency vibrations, including below 20 KHz, in a selected element of the body by use of a driver; determining parameters of the vibration exerted on the body by the driver; sensing variations of a dimension of the element of the body over time, including in response to the driver; correlating the variations with frequency components of operation of the driver below 20 KHz to determine corresponding frequency components of the variations; resolving the frequency components into components of vibration mode shape; and determining the mechanical characteristics of the element on the basis of the parameters of vibration exerted by the driver and of the components of vibration mode shape.

Abstract: A fast and reliable method is disclosed for measuring the dynamic mechanical properties of a material, particularly its modulus of elasticity and loss factor. By this method the acoustic characteristics of a material can be determined. An elongate strip of material, whose properties are desired to be known, is provided with miniature accelerometers fixedly secured to its opposite ends. One end of the strip is excited by a random noise source which travels toward the other end where that end and accelerometer is allowed to move freely (unrestrained). The accelerometers measures the ratios of acceleration at two locations over an extended frequency range of 0.2 Hz to 25 KHz, and the information is processed through a fast fourier transform spectrum analyzer for determining amplitude of acceleration ratio and phase difference between the two accelerometers from which Young's modulus and loss factor for that material are determined.

Abstract: A method and apparatus for measuring the dynamic material constants of rur compounds. The rubber compound is tested in strip form by attaching one end of the strip to an electromechanical shaker while the opposite end of the strip is suspended under constant tension. The electromechanical shaker propagates an acoustic wave in the test strip and a piezoelectric transducer positioned at a first point on the test strip measures the mechanical response of the strip for phase and amplitude. The shaker is programmed to step piecewise over the frequency range from 100 Hz to 40 KHz by a frequency synthesizer. The distance between the shaker and the transducer is changed and data is obtained for a second point on the strip. The test values obtained are used to calculate Young's Modulus and the loss factor for the rubber compound.

Abstract: An apparatus for measuring mechanical characteristics of a material capable of transmitting vibration, particularly skin of a living subject. An impulse from a generator such as a small hammer causes a disturbance to propagate a wave along the material. A receiver includes a source of radiation and two photocells spaced apart and isolated from each other. The photocells receive the radiation after reflection from spaced locations on the surface of the material. The travel time of the propagated wave between the two reflection points is measured to determine the speed of wave propagation in the material.