Abstract: The present invention provides a test device for a quasi zero stiffness isolator, and belongs to the technical field of vibration response tests of isolators. The device comprises a negative stiffness adjusting mechanism, a positive stiffness adjusting mechanism, and a beam-damping block mechanism. The negative stiffness adjusting mechanism and the positive stiffness adjusting mechanism are connected successively and installed on a beam-mass block system. The test device for the quasi zero stiffness isolator can realize smooth longitudinal vibration of a tested system, and can also flexibly adjust the positive stiffness value and the negative stiffness value of an overall mechanism. The present invention is suitable for a vibration model test of the quasi zero stiffness isolator, and solves the problems of complicated use method, impossibility of flexible adjustment of mechanism stiffness and complicated replacement process of stiffness elements in the device for the existing quasi zero stiffness isolator.

Abstract: A surface monitoring device is for monitoring a contact surface of a detected object. The surface monitoring device and the detected object are disposed on a substrate. The surface monitoring device includes a resonant mechanical part, having a contact tip adjacent to the contact surface by a preset gap in a static state. A driving circuit, applying an AC input signal to drive the resonant mechanical part to cause the contact tip to vibrate with respect to the contact surface at a plurality of sampling frequencies. The contact tip substantially hits the contact surface in a tapping bandwidth within the sampling frequencies. An analysis circuit to analyze a ratio of an output voltage to an input voltage of the input signal and determine the tapping bandwidth, wherein the ratio in the tapping bandwidth is jumping to a flatten phase.

Abstract: A vibration structure that includes a film having a first electrode on a first main surface thereof, the first electrode defining a first connection region on the first main surface where the first electrode is not present, and the film is constructed to be deformed in a plane direction when a voltage is applied thereto; a frame-shaped member; a vibration portion surrounded by the frame-shaped member; a first connection member that connects the first main surface of the film to the frame-shaped member at the first connection region; a second connection member that connects the film to the vibration portion; and an extended electrode that is connected to the first electrode.

Abstract: A system and method for generating input signals for an electronic engine control module includes a first waveform generator that is configured to generate a simulated first speed signal that is representative of a first speed and a vibration modulating signal that is representative of the first speed, a second waveform generator that is synchronized with the first waveform generator is configured to receive the vibration modulating signal and to generate a simulated second speed signal that is representative of a second speed and a simulated composite vibration voltage signal, and a voltage-to-charge converter that is configured to receive the simulated composite vibration voltage signal from the second waveform generator and to generate a simulated composite vibration charge signal that simulates a speed/vibration composite signal from an accelerometer.

Abstract: A position-measuring device includes a graduation carrier which is non-rotatably connectable to a shaft and has a measuring graduation that is disposed radially about an axis of rotation of the shaft in a mounted state of the graduation carrier. A first scanner is configured to generate position signals by scanning the measuring graduation. A position-processor is configured to process the position signals into absolute, digital position values. An interface is configured to communicate with subsequent electronics. A second scanner is configured to generate measurement signals that are dependent on a position of a machine part by scanning a measurement target on the machine part. An analyzer is configured to process the measurement signals into a measurement value indicative of a position and/or a change in the position of the measurement target relative to the second scanner, and to output the measurement value to the interface.

Abstract: A test apparatus for simulating a seismic dynamic response of an underground cavern includes a loading frame, an overlying model and an underlying model of the underground cavern, a static loading device, a dynamic loading device and a measuring device. A vertical load and a horizontal load are separately applied by the static loading device to the overlying model to simulate real vertical and horizontal in-situ stresses of the in-situ underground cavern. A seismic dynamic load is applied by the dynamic loading device to the underlying model, and then acts on the overlying model to simulate a real seismic ground motion on the in-situ underground cavern. In this way, the present invention satisfies simulation requirements for the seismic dynamic response of the underground cavern to implement a high-fidelity simulation on the underground cavern through unified loading of the in-situ stress static load and the seismic dynamic load.

Abstract: A vibration testing system (VTS) including a vibration testing apparatus, which includes a power amplifier operatively coupled to an electrodynamic shaker. The shaker includes a vibrateable armature mechanically coupled to a payload support structure. A data logger measures and records respective values of operational parameters of the shaker over time during mechanical excitation of the payload. A controller of the VTS reads and processes logged values of the operational parameters and determines an accumulated number of armature force cycles based on the recorded values of the operational parameters. The controller computes a remaining service-life or a consumed service life of the electrodynamic shaker based on the accumulated number of armature force cycles and a predetermined service-life of the vibration testing apparatus. The controller indicates on a display of the VTS the remaining service-life or the consumed service life of the vibration testing apparatus.

Abstract: An object of the invention is to provide a technology for further improving scanning performance. Provided is an optical scanning device including: a scanning unit including an optical waveguide configured to guide incident light and emit the light from an emission end, and a vibration unit configured to generate a vibration and vibrate the emission end; and a signal transmission unit configured to transmit a signal to the scanning unit and cause the scanning unit to scan an object, characterized in that the scanning unit includes a first bonding and vibration attenuating unit configured to bond, with an elastic member, an end surface of the vibration unit closer to the emission end and the optical waveguide.

Abstract: A method for driving a vibrating motor is provided in the present disclosure. The method includes the following steps: providing a driving signal to a vibrating motor; detecting a vibration direction of a vibrating unit of the vibrating motor; determining whether the driving signal facilitates vibration of the vibrating unit; and switching a polarity of the driving signal when the driving signal does not facilitate the vibration of the vibrating unit.

Abstract: In a liquid ejecting head, a vibration plate includes an effective displacement portion provided for each pressure chamber and an island-shaped part which is provided in the effective displacement portion at a position on the opposite side to the pressure chamber and to which one end portion of a piezoelectric vibrator is bonded; the piezoelectric vibrator has a laminate structure in which electrodes and piezoelectric material are alternately laminated; a layer at an end of one side of the piezoelectric vibrator in the laminating direction is formed of an external electrode, while a layer at an end of the other side thereof in the same direction is formed of a piezoelectric material; and the piezoelectric vibrator is disposed so as to be shifted toward the other side in the laminating direction with respect to the effective displacement portion.

Abstract: A control method for a mechanical vibration system independently modifies the higher and lower frequency components of the drive signal satisfying a target profile in a manner that limits displacement in the driven vibration. In particular, phases of the lower frequency components in a preliminary drive spectrum are independently adjusted so that peaks of the respective components are non-simultaneous and distributed in time to avoid contributing constructively. For example, the lower frequency components may be applied as a filter to a narrow-band time waveform, such as one with a swept frequency, to obtain the lower-frequency time waveform. The higher frequency components are randomized in their phase, transformed into the time domain, and recombined with the lower frequency part to obtain the drive signal.

Abstract: A tray assembly for balancing weights is disclosed. The tray assembly has trays of different sizes adapted to different sizes of the balancing weights. This results in that the balancing weights are all positioned in the same height, and therefore can easily be picked up by a handling system. The size of the tray may automatically be adjusted by slides operated by actuators. The tray may be a horizontal rotating tray assembly which preferably has a conical form, thus allowing a plurality of handling systems, picking up balancing weights at the same time. This results in a significantly improved loading speed.

Abstract: A method is provided for evaluating a tire. The method includes impacting the tire with a force; measuring motion information; extracting the resonant frequencies from the measured motion information; and calculating stiffness characteristics of the tire from the resonant frequencies.

Abstract: A method of carrying out alignment between a substrate and a mask, each having respective alignment marks. Vibrations attic substrate in a direction of gravity are measured. An antiphase vibrational wave is calculated, based an data corresponding to the measured vibrations. The antiphase vibrational wave is applied to the substrate, thereby reducing the vibrations or the substrate. When the vibrations of the substrate in the direction of gravity fall within a predetermined value that is set in advance, images are taken of relative positions of the alignment marks provided on the substrate and the mask, respectively, from the substrate side, and corresponding data is produced. Based on the data corresponding to the obtained images, an amount of movement of one of the substrate and the mask is calculated in a horizontal direction. One of the substrate and the mask is moved, based on the calculated movement amount.

Abstract: An acceleration device includes an actuator configured to displace a mass in a reciprocating motion at a desired frequency, a mount configured to hold a device, such as an accelerometer device, and at least one spring connecting the mount to the mass. The actuator is used to apply a force to achieve resonance. The actuator may comprise a voice coil motor, wherein the voice coil motor includes a permanent magnet and an armature and wherein said armature comprises part of said mass. The actuator applies a periodic force to the mass. The periodic force may be a sinusoidal force. Preferably, the applied force is aligned with a resulting velocity of the mass. The mount may include a test socket to which the device is electrically connected. The spring may comprises one or more flexure elements. The acceleration device may be used with a handler device to connect and disconnect the device to and from the mount. Optionally, the handler device includes an environmental chamber surrounding the mount.

Abstract: A new signal acquisition concept is provided for MEMS components having a pressure-sensitive diaphragm element, which at least partially spans a pressure connection opening. This signal acquisition concept is distinguished by an especially high sensitivity. For this purpose, the MEMS component includes a resonant vibrator device having a vibrating element, which is suspended, capable of vibrating, within a closed cavity and is equipped with at least one drive electrode and at least one sensing electrode. The vibrating element of the resonant vibrator device is coupled mechanically to the diaphragm element, so that the vibrating element is deformed in the case of a diaphragm deflection.

Abstract: A floor panel comprises: an article storage portion formed to protrude downwardly at a position spaced apart from each of two frame members on vehicle widthwise opposite sides thereof; and a pair of right and left lateral coupling portions each provided between a respective one of the frame members and the article storage portion. A storage bottom of the article storage portion has an upwardly or downwardly convex curved surface, and a storage wall of the article storage portion is configured such that each of right and left upper ends thereof is located below a corresponding one of two joint sections between respective ones of the lateral coupling portions of the floor panel and respective ones of the frame members. At least one of the pair of lateral coupling portions is formed by a downwardly inclined planar or curved surface.

Abstract: An accelerated powder segregation testing apparatus and method are disclosed. The apparatus consists of an angularly oriented ramp 10 mounted on a vibration device 22. The powder to be tested is fed into an origin portion 14 of the ramp 10, and when the vibrator 22 is activated, the powder moves along the ramp 10. As the powder exits after the test, unit-dose powder samples are collected, compacted and analyzed for differential in content uniformity. By comparing the results from several formulations, the formulation that is most resistant to segregation can be selected for production.

Abstract: A gyro sensor includes a vibrator and a drive circuit. A PWM drive signal is applied to a pair of electrodes of the vibrator. The drive circuit outputs a high level signal and a low level signal to the electrodes as the PWM drive signal. The high level signal and the low level signal have potentials higher and lower than that of the reference signal, respectively. The drive circuit outputs the high level signal to one of the pair of electrodes and the low level signal to the other of the pair of electrodes.

Abstract: An evaluation method for evaluating the performance of an image stabilization function of an imaging apparatus includes: a first imaging step of imaging an object, with the image stabilization function being ON and the imaging apparatus being vibrated; a second imaging step of imaging the object, with the imaging apparatus being static; a first calculation step of calculating a first shutter speed based on the image taken in the first imaging step, and calculating a first evaluation value based on the first shutter speed and a reference shutter speed; a second calculation step of calculating a second evaluation value based on the images taken in the first and second imaging steps; and an evaluation step of calculating an evaluation value of the performance of the image stabilization function of the imaging apparatus, based on a result of subtraction of the second evaluation value from the first evaluation value.

Abstract: A vibration test fixture includes a shaker and a slip plate coupled with the shaker. A mounting plate may be coupled with the slip plate and a cylindrical bridge may be coupled with the mounting plate. A sensor may be coupled with the bridge.

Abstract: A method includes receiving a representation of a volume acceleration of a seismic vibrator. The method includes determining a signature of the seismic vibrator based at least in part on the representation of the volume acceleration.

Abstract: A system for detecting a spike killed cross-tie comprising a magnet positioned over a railroad fastener. The magnet has a pull force that is at least about 50 lbs, but less than the holding force of a railroad fastener in an undamaged cross-tie or less than about 6,000 lbs.

Abstract: The present disclosure relates to piezoelectric sensors and piezoelectric sensor arrays, to methods of manufacturing therefor, and to a method of measuring characteristics of a mechanical wave using a piezoelectric sensor array. A piezoelectric sensor is formed of a silicon substrate on which an electrical barrier is added. A patterned bottom electrode layer is added on top of the electrical barrier. A patterned bottom electrode layer is added on top of the electrical barrier. A piezoelectric layer and then a patterned top electrode layer are added on top of the electrical barrier.

Abstract: A method for ground probing includes providing a vibrator arrangement held on a carrier device, designed to penetrate the ground, and comprising a vibrator motor; inserting the vibrator arrangement into the ground, to a pre-determined depth; and determining a ground profile of the ground as the vibrator arrangement is inserted. The determination of the ground profile comprises the measurement of at least one operating parameter of the vibrator arrangement during the insertion into the ground, and the ground profile comprises a respective ground parameter for at least two different ground depths.

Abstract: A system and method for adjusting the light output of an optoacoustic imaging system is presented. An optoacoustic imaging system includes a light source such as a laser, the light source having a light output control, a probe for delivering light to a volume, the probe being associated with one or more sensors, a light path operatively connected to the first light source, the light path providing light from the first light source to the probe. Generally, the light output of an optoacoustic imaging system may be harmful to the eye, and may be subject to maximum safe fluence levels incident upon the volume of interest in a clinical setting. Accordingly, the light output control may be set to an initial, relatively low value. After the light source is pulsed, the light output may be measured at or near the probe at the distal end of the light path. The measured light output can used to determine whether, and how much, to change the setting of the light output control.

Abstract: A method and apparatus for testing an object. A testing unit comprises a base structure, a contact structure, and piezoelectric transducers. The piezoelectric transducers are located between the base structure and the contact structure. A preload is present on the piezoelectric transducers.

Abstract: An object of the invention is to accurately detect a state of an object to be heated in a cooking vessel and effectively avoid cooking failure. An induction heating section (13) inductively heats a cooking vessel (11). A vibration detecting section (14) detects a vibration of the cooking vessel (11) via a top plate (12). A vibration waveform extracting section (15) extracts a vibration waveform of a frequency component having a frequency equal to a predetermined multiplication product of an induction heating frequency, from a waveform of the vibration detected by the vibration detecting section (14). A determining section (16) determines a state of an object to be heated, based on the vibration waveform extracted by the vibration waveform extracting section (15).

Abstract: A method and apparatus for determining phase sensitivity of an accelerometer based on an analysis of the harmonic components of the interference signal, which can estimate phase lags of an accelerometer through an analysis of the interference signal obtained using a single photo-detector when the accelerometer moves in sinusoidal motion with an initial phase of vibration. The method comprises the steps of obtaining an interference signal in a time domain generated from a signal reflected by an accelerometer and a fixed mirror using a single photo-detector; transforming the interference signal in the time domain into a signal in a frequency domain including a plurality of harmonic signals by Fourier transform; and determining the phase sensitivity of the accelerometer using initial phase of vibration displacement of the accelerometer, which is included in the interference signal in the frequency domain.

Abstract: A reference vibrator 10 of the present invention includes: a vibrator body 11 configured to mount to a mount 4 in an unbalance measurement device 1 to which a rotary product is mounted at the time of unbalance measurement, in a same mounting state as the rotary product; a vibration generator 12 fixed to the vibrator body 11 and that applies vibrations to the vibrator body 11; and a control unit 13 that controls the vibration generator 12. Because vibration is caused by the vibration generator 12 fixed to the vibrator body 11, repeatability of vibration force is high. This makes it possible to apply vibrations for repeatability check to the unbalance measurement device 1 with an accurate vibration force. Thus, variations in vibration force can be eliminated, and the repeatability of the unbalance measurement device 1 can be properly checked.

Abstract: The disclosure relates to a test process of an image stabilization system in an image capture apparatus, comprising steps of: submitting the stabilization system to rotation vibratory movements around two distinct rotation axes, measuring characteristics of rotation vibratory movements, and setting the rotation vibratory movements to setpoint position values and, taking into consideration the measured characteristics of the vibratory movements, collecting images from the image capture apparatus submitted to vibration and analyzing the collected images.

Abstract: Provided are devices, systems, and methods for the testing of materials and structures. For example, the devices, systems, and methods are optionally used for the non-destructive testing of a material or structure. Furthermore, the devices, systems, and methods may optionally use a high-amplitude, air-coupled acoustic source for non-destructive testing of materials and structures.

Abstract: An apparatus for generating vibrations in a component comprising a clamp assembly for clamping the component and a vibration generator for generating vibrations in the clamped component, the clamp assembly including: a base member, a pair of fixedly-spaced clamp members and a wedge for laterally wedging part of the component between the clamp members thereby to clamp the component. The base member, or a fixed clamp member, is inclined and the wedge having an inclined wedging surface arranged to engage the inclined base member or inclined fixed clamp member. The apparatus may form part of a test rig for vibration testing components such as turbo machine blades.

Abstract: A vibrating element includes: a first support portion and a second support portion; a first vibrating arm which extends along a first axis, one end of the first vibrating arm being connected to the first support portion; a second vibrating arm which extends along the first axis, one end of the second vibrating arm being connected to the second support portion; an oscillating member which is sandwiched between the other ends of the first vibrating arm and the second vibrating arm, and has openings; and detection arms which extend along a second axis perpendicular to the first axis from the inner walls of the openings of the oscillating member in plan view.

Abstract: A nacelle test apparatus for testing a wind turbine nacelle is provided. The test apparatus includes a physical tower model apparatus realised to model the behaviour of a wind turbine tower and/or a physical rotor model apparatus realised to model the behaviour of a wind turbine rotor, and an exciter apparatus for exciting a physical model apparatus. Also provided is a method of testing a wind turbine nacelle, which method includes mounting the nacelle onto a physical tower model apparatus of a nacelle test apparatus, which physical tower model apparatus is realised to model the behaviour of a wind turbine tower, and/or mounting a physical rotor model apparatus of the nacelle test apparatus to a hub of the nacelle, which physical rotor model apparatus is realised to model the behaviour of a wind turbine rotor, and exciting the physical tower model apparatus and/or the physical rotor model apparatus.

Abstract: A vibration test fixture includes a shaker and a slip plate coupled with the shaker. A mounting plate may be coupled with the slip plate and a cylindrical bridge may be coupled with the mounting plate. A sensor may be coupled with the bridge.

Abstract: A quartz resonator flow cell has a piezoelectric quartz wafer with an electrode, pads, and interconnects disposed on a first side thereof. The piezoelectric quartz wafer has a second electrode disposed on a second side thereof, the second electrode opposing the first electrode. A substrate is provided having fluid ports therein and the piezoelectric quartz wafer is mounted to the substrate such that the second side thereof faces the substrate with a cavity being formed between the substrate and the wafer. The fluid ports in the substrate are aligned with the electrode on the second side of the piezoelectric quartz wafer which is in contact with the cavity.

Abstract: An apparatus for sonic excitation of a surface has a housing defining an open cavity facing the surface. At least one speaker is positioned to introduce sound to the cavity. The housing comprises a gasket for sealing with the surface. A valve is coupled to the cavity to allow the cavity to be maintained at a pressure below an external pressure.

Abstract: An exemplary vibration testing device includes two mounting bases, a vibration generator located between the mounting bases, two pivot shafts, a supporting platform, two supporting elements and a control system. Each supporting element is telescopically extendable and retractable. The control system includes a lift control unit for controlling telescopic movement of the supporting elements, a first rotary control unit for controlling a rotationally movement of the vibration generator about the pivot shafts, and a second rotary control unit for controlling rotatable movement of the supporting elements about the pivot shafts. The control system is configured for controlling the vibration testing device to move between a first testing status in which vertical vibration forces are generated by the vibration generator and applied to the supporting platform and a second testing status in which horizontal vibration forces are generated by the vibration generator and applied to the supporting platform.

Abstract: A microelectronic device tester has a mounting member (for mounting a device), a drive shaft connected to the mounting member, and a vibration shaft mechanically in communication with the drive shaft. The drive shaft and vibration shaft are non-coaxial, and the drive shaft has a drive shaft proximal end and a drive shaft distal end. The drive shaft proximal end is connected to the mounting member, and the drive shaft distal end terminates proximal of the entire vibration shaft.

Abstract: A seismic vibrator has a baseplate composed at least partially of a composite material. The baseplate has a body composed of the composite material and has top and bottom plates composed of a metallic material. The top plate supports isolators for isolating the vibrator's mass and frame from the baseplate. Internally, the composite body has a central structure to which couple stilts for supporting the mass and a piston for the vibrator's actuator. A lattice structure surrounds the central structure. This lattice structure has radial ribs extending from the central structure and has radial ribs interconnecting the radial ribs.

Abstract: An acoustic sensor system includes a first plurality of acoustic sensors, and an acoustic transmitter structured to generate acoustic noise to mimic acoustic noise induced by an electrical conductivity fault. A smaller second number of acoustic sensors of the first plurality of acoustic sensors are structured to identify a plurality of locations in an electrical distribution system having a plurality of electrical joints, in order that the smaller second number of acoustic sensors can monitor the plurality of electrical joints of the electrical distribution system.

Abstract: A method and apparatus for testing an object. A testing unit comprises a base structure, a contact structure, and piezoelectric transducers. The piezoelectric transducers are located between the base structure and the contact structure. A preload is present on the piezoelectric transducers.

Abstract: A vibrating meter (5) is provided. The vibrating meter (5) includes one or more conduits (103A, 103B) including a vibrating portion (471) and a non-vibrating portion (472) and a driver (104) coupled to a conduit of the one or more conduits (103A, 103B) and configured to vibrate the vibrating portion (471) of the conduit at one or more drive frequencies. The vibrating meter (5) also includes one or more pick-offs (105, 105?) coupled to a conduit of the one or more conduits (103A, 103B) and configured to detect a motion of the conduit. One or more meter components exclusive of the vibrating portion (471) of the conduits (103A, 103B), the driver (104), and the pick-offs (105, 105?) is provided with a damping material (310) applied to at least a portion of a surface of a meter component of the one or more meter components that reduces one or more vibrational resonant frequencies of the meter component below the one or more drive frequencies.

Abstract: An angular velocity detection circuit is connected to a resonator for making excited vibration on the basis of a drive signal and detects an angular velocity. The angular velocity detection circuit includes: a self-vibration component extraction unit that receives, from the resonator, a detection signal including an angular velocity component based on a Coriolis force and a self-vibration component based on the excited vibration and extracts the self-vibration component from the detection signal; a direct-current conversion unit including an integration unit that integrates an output signal of the self-vibration component extraction unit; and a temperature characteristic compensation unit that compensates for a variation due to a temperature in an output signal of the direct-current conversion unit.

Abstract: An electrostatic capacitive vibration sensor has a substrate, a through-hole, a vibrating electrode plate, and a fixed electrode plate opposite the vibrating electrode plate. The fixed electrode plate is subjected to vibration to perform membrane oscillation. Pluralities of acoustic holes are made in the fixed electrode plate. The vibrating and fixed electrode plate are disposed on a surface side of the substrate such that an opening on the surface side of the through-hole is covered. A lower surface of an outer peripheral portion of the vibrating electrode plate is partially fixed to the substrate. A vent hole that communicates a surface side and a rear surface side of the vibrating electrode plate is made between the surface of the substrate and the lower surface of the vibrating electrode plate. In addition, the acoustic hole has a smaller opening area except at the outer peripheral portion.

Abstract: The electrostatic sensors of bridge or cantilever type with multiple electrodes, the electrostatic sensors of comb type and piezoelectric sensors are used for the single molecule detection of ligands. The electrical driving of sensors is separated in some cases from the sensing for increased sensitivity. The large arrays of sensors with individual or common sensing circuits are employed to further improve detection sensitivity. The fabrication of the sensors, their functionalization for detection of many chemical and biological species and electrical circuitry, packaging, microfluidic subsystem and the system architecture are also disclosed. The individual, specific sensing of single species or simultaneous detection of multiple species is realized. The freeze drying or critical point drying after exposure of sensors to ligands present in liquids and detection in reduced pressure or vacuum is employed for increased sensitivity, down to the single molecule.

Abstract: The invention is a vibration sensor with a carrying element capable of being set into vibration; a conversion device having a field coil to set and/or tap the carrying element into vibration; an anchor mounted in the field coil; and, a vibration element to transmit the vibrations from the carrying element into/from a surrounding space. The anchor is designed as two parts, having a permanent magnet and a coil core connected to the field coil, with an air gap arranged therebetween and lying in the area of the axial extension of the field coil. The permanent magnet is connected to the carrying element to transmit vibrations; and, the field coil and the permanent magnet are arranged to interact in such a way that any vibration of the permanent magnet induces current flow in the field coil and/or induces vibration of the permanent magnet in the field coil.

Abstract: A vibration excitator including a main body, a stinger which is adapted to move relative to the main body, in a particular working direction, an actuator coupled to the main body and the stinger, wherein the stinger has a first end that is coupled to the main body, and an opposite second end that is intended for attachment to an object to be examined, wherein the stinger has an elastic center point, wherein the main body has a center of gravity, and wherein L1=L3 applies, wherein L1 is the distance between the elastic center point and the second stinger end, measured along the said working direction, and wherein L3 is the distance between the center of gravity and the second stinger end, measured along the said working direction.

Abstract: A driver for applying an oscillating stress to a subject undergoing a medical imaging procedure, such as with magnetic resonance elastography (MRE), includes a passive driver located in the bore of the magnet and in direct contact with the skin of the subject. A remotely located active driver includes a linear motor and a sealed diaphragm that produces acoustic pressure waves in response to an applied current. The pressure waves are directed through a tube and into a chamber formed within the passive driver. Vibrations produced in response to the pressure waves create shear waves that are directed into the subject to aid in the imaging procedure.