Abstract: A sensor device that senses proper acceleration. The sensor device includes a substrate, a spacer layer supported over a first surface of the substrate, at least a first tapered cantilever beam element having a base and a tip, the base attached to the spacer layer, and which is supported over and spaced from the substrate by the spacer layer. The at least first tapered cantilever beam element tapers in width from the base portion to the tip portion. The at least first cantilever beam element further including at least a first layer comprised of a piezoelectric material, a pair of electrically conductive layers disposed on opposing surfaces of the first layer, and a mass supported at the tip portion of the at least first tapered cantilever beam element.

Abstract: A method and structure for a single crystal acoustic electronic device. The device includes a substrate having an enhancement layer formed overlying its surface region, a support layer formed overlying the enhancement layer, and an air cavity formed through a portion of the support layer. A single crystal piezoelectric material is formed overlying the air cavity and a portion of the enhancement layer. Also, a first electrode material coupled to the backside surface region of the crystal piezoelectric material and spatially configured within the cavity. A second electrode material is formed overlying the topside of the piezoelectric material, and a dielectric layer formed overlying the second electrode material. Further, one or more shunt layers can be formed around the perimeter of a resonator region of the device to connect the piezoelectric material to the enhancement layer.

Abstract: A resonator element includes a quartz crystal substrate including a supporting section, a resonating section, and a coupling section coupling the supporting section and the resonating section and having thickness smaller than the thickness of the supporting section, the supporting section including a first principal plane and a first side surface coupling the first principal plane and the coupling section, a first excitation electrode disposed in the resonating section, a second excitation electrode disposed in the resonating section and overlapping the first excitation electrode via the resonating section, and first and second pad electrodes including portions disposed on the first principal plane, the first and second pad electrodes being electrically coupled to the first and second excitation electrodes.

Abstract: Provided is a terminal device. The terminal device includes: a housing; a display screen installed on the housing; a piezoelectric body parallel to the display screen and including a fixed end and a free end, the fixed end being fixed on the housing, and the free end being opposite to the fixed end and being configured to vibrate under driving of an audio signal; and a vibrating body arranged between the display screen and the piezoelectric body, fixedly connected with the free end, and configured to vibrate in a direction perpendicular to the display screen with the vibration of the free end.

Abstract: Aspects of this disclosure relate to a surface acoustic wave filter with an integrated temperature sensor. The integrated temperature sensor can be a resistive thermal device configured as a reflective grating for a surface acoustic wave resonator, for example. A radio frequency system can provide over temperature protection by reducing a power level of a radio frequency signal provided to the surface acoustic wave filter responsive to an indication of temperature provided by the integrated temperature sensor satisfying a threshold.

Abstract: A piezoelectric device includes a foundation structure and a plurality of metal islands distributed over a first area of a top surface of the foundation structure. A piezoelectric film resides over the foundation structure and is formed from a piezoelectric material. The piezoelectric film has a non-piezoelectric portion over the first area and a piezoelectric portion over a second area of the top surface of the foundation structure. Within the non-piezoelectric portion, the piezoelectric film is polarity patterned to have pillars and a mesh. The pillars of the piezoelectric material have a first polar orientation residing over corresponding ones of the plurality of metal islands. The mesh of the piezoelectric material has a second polar orientation, which is opposite that of the first polar orientation, and surrounds the pillars. In one embodiment, the metal islands are self-assembled islands.

Abstract: An apparatus for disrupting solid materials suspended in a fluid medium includes a plurality of hammer elements that transfer acoustic energy from an acoustic transducer into a concentration zone between heads of the hammer elements and inner walls of a fluid duct which act as an anvil, thereby causing cavitations to form within the concentration zone. The transducer may be a cylindrical transducer compression fit into an acoustic projector from which the hammer elements extend towards a distal end, and mass balance elements extend towards a proximal end. The apparatus can be used to efficiently extract juice from fruit pulp, separate oils from plant matter, and process various organic and inorganic materials.

Abstract: In a quartz crystal unit, the unit comprising a case, and a resonator having a base portion, and first and second vibrational arms, the base portion having a first base portion including a first width, and a second base portion including a second width greater than the first width, each of the first and second vibrational arms having a first vibrational portion including a first width and a first length, and a second vibrational portion including a second width greater the first width and a second length less than the first length, the second base portion being mounted on a mounting portion of the case, at least one groove being formed in at least one of opposite main surfaces of the first vibrational portion of each vibrational arm, and a spaced-apart distance between the second vibrational portions of the first and second vibrational arms being less than a length of the second base portion of the base portion.

Abstract: A method of detecting a substance, wherein the method includes functionalizing a plurality of sensors, wherein the functionalizing the plurality of sensors comprises depositing a first material using a piezoelectrically actuated pipette system, wherein the first material includes a polymer, a receptor, and a solvent, wherein the solvent comprises dimethylformamide. The method further includes evaporating a solution of the first material wherein a residue after the evaporation comprises a functionalized chemical. Additionally, the method includes introducing a control material to a first set of sensors of the plurality of sensors using the piezoelectrically actuated pipette system. Further, the method includes introducing a test material to a second set of sensors of the plurality of sensors using the piezoelectrically actuated pipette system, wherein the test material comprises an analyte.

Abstract: A micro-electromechanical device includes a semiconductor substrate, in which a first microstructure and a second microstructure of reference are integrated. The first microstructure and the second microstructure are arranged in the substrate so as to undergo equal strains as a result of thermal expansions of the substrate. Furthermore, the first microstructure is provided with movable parts and fixed parts with respect to the substrate, while the second microstructure has a shape that is substantially symmetrical to the first microstructure but is fixed with respect to the substrate. By subtracting the changes in electrical characteristics of the second microstructure from those of the first, variations in electrical characteristics of the first microstructure caused by changes in thermal expansion or contraction can be compensated for.

Abstract: A surgical instrument includes an ultrasonic transducer assembly comprising a coupling portion laterally movable at an ultrasonic frequency. In addition, the surgical instrument includes an ultrasonic transmission waveguide extending from the coupling portion and an ultrasonic treatment element defining a cutting surface, wherein the ultrasonic treatment element extends from the ultrasonic transmission waveguide, and wherein the lateral movement of the coupling portion is in a direction perpendicular to a plane defined by the cutting surface of the ultrasonic treatment element.

Abstract: A passive wireless sensor includes a substrate having at least one Microelectromechanical system (MEMS) piezoelectric resonator thereon. The MEMS piezoelectric resonator includes a piezoelectric layer between a top metal or semiconductor layer (top electrode layer) and a bottom metal or semiconductor layer (bottom electrode layer). The top electrode layer is a patterned top electrode layer including at least a first electrode for sensing an electrical signal and a second electrode for providing a ground reference. An antenna is connected to the first and/or second electrode for wirelessly transmitting the electrical signal and for receiving a wireless interrogation signal.

Abstract: A BAW resonator/filter with a monolithic TFE package that defines an acoustic BC and suppresses resonances from the low-Q piezoelectric area of the resonator and resulting devices are provided. Embodiments include a BAW resonator over a dielectric layer, the BAW resonator including a first metal layer, a thin-film piezoelectric layer, and a second metal layer; a first cavity in the dielectric layer under the first metal layer and a second cavity over the first cavity on the second metal layer; and a pair of TFE anchors on the second metal layer, each TFE anchor adjacent to and on an opposite side of the second cavity and extending beyond the first metal layer.

Abstract: Operational configuration and temperature compensation methods are provided for bulk acoustic wave (BAW) resonator devices suitable for operating with liquids. Temperature compensation methods dispense with a need for temperature sensing, instead utilizing a relationship between (i) change in frequency of a BAW resonator at a phase with adequate sensitivity and (ii) change in frequency of a phase that is correlated to temperature. Operational configuration methods include determination of an initial phase response of a BAW resonator in which temperature coefficient of frequency is zero, followed by comparison of sensitivity to a level of detection threshold for a phenomenon of interest.

Abstract: A sensor (2) is provided, having an acoustic resonator (18) for containing a fluid such as air and at least one transducer (22, 24) arranged to emit an acoustic signal into the acoustic resonator (18) in response to an excitation signal provided to the transducer (22, 24) by an electronic unit (4). The electronic unit (4) receives a response signal from at least one transducer (22, 24), and processes the excitation signal and the response signal to derive the acoustic signal response of the acoustic resonator. The pressure and/or temperature of the fluid may be derived from the acoustic signal response. More specifically, the electronic unit (4) may derive the temperature of fluid inside the acoustic resonator (18) by obtaining the resonant frequencies of the acoustic signal inside the acoustic resonator (18), or may derive the barometric pressure from the acoustic signal response in the vicinity of the fundamental frequency and its harmonics.

Abstract: A piezoelectric element includes a plate-shaped piezoelectric body having one principal face and the other principal face which are opposite to each other; and a first surface electrode mounted on the one principal face and a second surface electrode mounted on the other principal face, at least one of the first surface electrode and the second surface electrode including a center part and a peripheral part which is greater in thickness than the center part, the peripheral part having a thicker region and a thinner region which is thinner than the thicker region.

Abstract: A crystal resonator vibrates in a thickness-shear mode. The crystal resonator includes excitation electrodes being disposed on a front surface and a back surface of a crystal element. The excitation electrodes are disposed on the crystal element to have a positional relationship, where a displacement distribution at an edge of the excitation electrode on the front surface is identical to a displacement distribution at an edge of the excitation electrode on the back surface.

Abstract: According to some embodiments, an accessory device for interacting with an electronic device having a touch sensitive surface, is described. The accessory device can include a housing having walls suitable for carrying a processor capable of providing instructions and an interface unit extending through an opening at a distal end of the housing, where the interface unit is capable of interacting with the touch sensitive surface. The accessory device can further include a sensor in communication with the processor and the interface unit, where the sensor is capable of (i) detecting a stimulus generated by the interaction between the interface unit and the touch sensitive surface, and (ii) responding by providing a feedback parameter to the processor that responds by providing a feedback instruction. The accessory device can further include a feedback component that responds to the feedback instruction by transmitting a feedback force to the walls of the housing.

Abstract: A resonator is provided that suppresses frequency variations with etching without decreasing the strength of vibration arms. The resonator includes a base portion, a first vibration portion extending from the base portion in a first direction and having a first width, and a second vibration portion extending from the base portion in the first direction with a first gap between the first and second vibration portions and having the first width. The first and second vibration portions perform out-of-plane bending vibration with opposite phases at a predetermined frequency. The predetermined frequency varies in accordance with the first width and the first gap. The ratio of the first gap to the first width is within a range that causes an absolute value of rates of variations in the predetermined frequency with respect to variations in the first width and in the first gap to be not more than about 100 ppm.

Abstract: An electronic device may include: a rotation detection module configured to detect rotation parameters of a rotating body; a haptic module configured to generate vibration according to a vibration pattern; a display configured to display a user interface; a memory; and a processor electrically connected with the rotation detection module, the haptic module, the display, and the memory. The memory may store instructions that, when executed, cause the processor to: determine vibration parameters based on the rotation parameters detected by the rotation detection module; generate a vibration pattern based on the vibration parameters; and output a user interface corresponding to the generated vibration pattern on the display.

Abstract: A resonator that includes a base and one or more vibration arms with fixed ends connected to a front end of the base and open ends extending therefrom. Moreover, the vibration arms include first and second electrodes and a piezoelectric film that is disposed therebetween. The resonator further includes a protective film disposed opposing an upper face of the piezoelectric film and sandwiching the first electrode and a temperature characteristics adjusting film formed of a material different from a material of the protective film and that is provided on the fixed end side relative to the center of the vibration arms such that part of the protective film is exposed to a surface.

Abstract: A Bulk Acoustic Wave (BAW) resonator with an electrically isolated Border (BO) ring is provided. One BAW resonator includes a bottom electrode and a piezoelectric layer over the bottom electrode and having a top surface with a first portion and second portion about the first portion. The BAW resonator also includes a top electrode over the first portion of the piezoelectric layer and a BO ring including a non-conductive portion that is over the second portion of the piezoelectric layer and adjacent to the piezoelectric layer. The BAW resonator may be a Solidly Mounted BAW (SMR-BAW) resonator or a Film BAW Resonator (FBAR). A radio frequency filter including a ladder configuration with the above BAW resonator as a series BAW resonator and methods for fabricating the above BAW resonator are also provided.

Abstract: The specification and drawings present packaging for integrating a microphone into an outdoor luminaire that provides high sensitivity and dynamic range together with being waterproof, resistant to impact and wind noise, environmentally resistant and unobtrusive to passers-by. Various embodiments describe packaging of outdoor luminaire mounted microphones to achieve waterproof and minimized unwanted noise performance, and other desirable features.

Abstract: A method for manufacturing a quartz crystal resonator that includes a quartz crystal blank having a vibrating portion including a center of a principal surface of the quartz crystal blank when viewed in plan from a direction normal to the principal surface and a peripheral portion adjacent to the vibrating portion, a pair of excitation electrodes disposed opposite to each other with the vibrating portion interposed therebetween, a pair of electrode pads disposed on the peripheral portion, and a pair of extended electrodes each extending from the vibrating portion to the peripheral portion to electrically connect one excitation electrode to a corresponding electrode pad, where the method includes conducting a first trimming of the vibrating portion and the peripheral portion; and conducting a second trimming of part of one of the excitation electrodes on the vibrating portion.

Abstract: The present disclosure provides a resonator which resonates in a bulk acoustic wave mode. The resonator includes a resonator body, at least one transducer arm and a substrate. The resonator body is deformed at least along a first direction. The transducer arm is connected to the resonator body along the first direction and includes a base, a piezoelectric layer and an electrode layer. The base includes a first end connected to the resonator body. The piezoelectric layer is disposed above the base but not extended to the resonator body, and the electrode layer is disposed above the piezoelectric layer but not extended to the resonator body. The substrate is for securing the transducer arm such that the resonator body is suspended.

Abstract: A robust low-cost wireless sensor with an internal battery, which permits operation for extended periods without the necessity of maintenance, for monitoring the flow of particulate solid material such as chemical fertilizers, small seeds, granulated foodstuffs, and others.

Abstract: A method of fabricating an acoustic wave device includes: forming a piezoelectric thin film resonator and a second lower electrode on a substrate, the piezoelectric thin film resonator having a resonance region in which a first lower electrode and a first upper electrode face each other across a piezoelectric film, the piezoelectric film and the first upper electrode are not formed on the second lower electrode outside the resonance region; forming a first dielectric film in the resonance region and a second dielectric film on the second lower electrode outside the resonance region at a same time, the first dielectric film and the second dielectric film being made of a material different from a material of the piezoelectric film; and forming a second upper electrode on the second dielectric film, the second upper electrode facing the second lower electrode.

Abstract: An isolator device comprises a first mount coupleable to an input structure subject to shock and/or vibration energy, a second mount coupleable to an object to be isolated (e.g., an electronics device). A flexure structure is coupled between the first and second mounts, and comprises a plurality of parallel flexures, a series of flexures, and a plurality of transition portions, all defining an isolation path between the first and second mounts. The parallel flexures are tuned to resonant frequency to attenuate shock and/or vibration in an axial direction relative to a normal axis. The series of radial flexures are tuned to resonant frequencies to attenuate shock and/or vibration energy in both radial directions relative to the normal axis. The isolator device can be a single piece of metallic material. An elastomeric damping material can be disposed within openings defined by the flexure structure to dampen response at the isolator's resonant frequency. Associated systems and methods are provided.

Abstract: Electronic devices and methods for fabricating electronic devices are provided. In one example, an electronic device includes an electronic device body structure having a substantially hermetically sealed cavity formed therein. A getter film is in fluid communication with the substantially hermetically sealed cavity. Conductive features are accessible from outside the substantially hermetically sealed cavity and are operatively coupled to the getter film for electrical communication with the getter film.

Abstract: An integrated device includes a MEMS device, such as a gyroscope, having a movable mass spaced apart from a substrate, the movable mass being configured to oscillate in a drive direction relative to the substrate. The integrated device further comprises an integrated circuit (IC) die having a surface coupled with the MEMS device such that the movable mass is interposed between the substrate and the surface of the IC die. An electrode structure is formed on the surface of the IC die, the electrode structure including a plurality of electrode segments vertically spaced apart from the movable mass. Openings extend through the movable mass and the electrode segments overlie the openings. Suitably selected electrode segments can be activated to electrostatically attract the movable mass toward sense electrodes vertically spaced apart from the MEMS to reduce quadrature motion of the movable mass.

Abstract: An ultrasound transducer array for coupling sonic energy into a liquid includes a plurality of transducer pairs, where each transducer pair includes an inverted ultrasound transducer and a non-inverted ultrasound transducer electrically coupled in series. A method for coupling sonic energy into a liquid includes (a) driving a first transducer pair with a first electrical signal, where the first transducer pair includes a first inverted ultrasound transducer and a first non-inverted ultrasound transducer electrically coupled in series and (b) driving a second transducer pair with the first electrical signal, where the second transducer pair is electrically coupled in parallel with the first transducer pair, and where the second transducer pair includes a second inverted ultrasound transducer and a second non-inverted ultrasound transducer electrically coupled in series.

Abstract: The invention relates to a BAW resonator with reduced heat build-up. The heat build-up is reduced by a thermal bridge, which dissipates heat from the electro-acoustically active region to a support substrate, without impairing the acoustics of the resonator.

Abstract: An acoustic resonator device includes a bottom electrode disposed on a substrate over an air cavity, a piezoelectric layer disposed on the bottom electrode, and a top electrode disposed on the piezoelectric layer, where an overlap between the top electrode, the piezoelectric layer and the bottom electrode over the air cavity defines a main membrane region. The acoustic resonator device further includes at least one metal frame disposed on a bottom surface of the bottom electrode having a thickness that ranges from about 10% to about 75% of a thickness of the bottom electrode in a central region of the bottom electrode. The thickness of the metal frame improves heat dissipation out of the acoustic resonator device while also improving structural stability of the acoustic resonator device without detrimentally affecting its performance.

Abstract: Systems and techniques are provided for transducer array subdicing. A laminate material may include two laminate material flexures which each have a flexure boundary defined by a gap in the piece of laminate material. A trench may be located between the two flexures. The trench may be defined by a removal of a portion of laminate material from the piece of laminate material. A second trench may be on an opposite surface of the piece of laminate material from the trench. The second trench may be partially aligned with the trench. The trench and the second trench may result from the removal of laminate material from the piece of laminate material to a depth of 20% to 60% of the thickness of the piece of laminate material.

Abstract: A quartz crystal resonator unit has an overall length less than 2.1 mm and a base portion having a length less than 0.5 mm and a width less than 0.55 mm, vibrational arms, and mounting arms connected to the base portion through connecting portions. Each vibrational arm has a first vibrational portion including a first width and a first length within a range of 0.32 mm to 0.72 mm and a second vibrational portion including a second width greater than the first width and a second length less than the first length. A groove is formed in at least one main surface of the first vibrational portions of the vibrational arms, a width of the groove being less than 0.07 mm and a distance in the width direction of the groove being less than 0.015 mm. A width of the mounting arms is less than 0.45 mm and a width of the connecting portion is less than 0.41 mm.

Abstract: The present invention relates to a filter chip (1), comprising an interconnection of at least one first and one second resonator (2, 3) operating with bulk acoustic waves, wherein the first resonator (2) operating with bulk acoustic waves comprises a first piezoelectric layer (4) that is structured in such a way that the first resonator (2) has a lower resonant frequency than the second resonator (3).

Abstract: A piezoelectrically transduced resonator device includes a wafer having a substrate, a buried oxide layer formed on the substrate, and a device layer formed on the buried oxide layer, and a resonator suspended within an air gap of the wafer above the substrate, the resonator including a portion of the device layer, a piezoelectric layer, and top and bottom electrodes contacting top and bottom sides of the piezoelectric layer, wherein the portion of the device layer is not directly connected to the wafer and wherein the resonator is configured to move relative to the substrate under electrostatic force to tune the frequency of the resonator device when a direct current voltage is applied between the substrate and the portion of the device layer of the resonator.

Abstract: An electrical circuit assembly can include a semiconductor integrated circuit, such as fabricated including CMOS devices. A first lateral-mode resonator can be fabricated upon a surface of the semiconductor integrated circuit, such as including a deposited acoustic energy storage layer including a semiconductor material, a deposited piezoelectric layer acoustically coupled to the deposited acoustic energy storage layer, and a first conductive region electrically coupled to the deposited piezoelectric layer and electrically coupled to the semiconductor integrated circuit. The semiconductor integrated circuit can include one or more transistor structures, such as fabricated prior to fabrication of the lateral-mode resonator. Fabrication of the lateral-mode resonator can include low-temperature processing specified to avoid disrupting operational characteristics of the transistor structures.

Abstract: A MEMS component includes a lower electrode. The MEMS component also includes an upper electrode. The upper electrode overlies the lower electrode. The MEMS component also includes a first piezoelectric layer between the lower electrode and the upper electrode. The first piezoelectric layer has a first piezoelectric material comprising AlN and Sc.

Abstract: A component includes a carrier and a functional structure on the carrier. A thin-film cover covers the functional structure and is used as a mounting base for a circuit part, which is arranged over the thin-film cover. The circuit part is connected to the functional structure by means of a lead.

Abstract: An acoustic wave filter includes: one or more series resonators connected in series between an input terminal and an output terminal; and parallel resonators connected in parallel between the input terminal and the output terminal and formed of piezoelectric thin film resonators, wherein each of at least two resonators of the parallel resonators includes an additional film having island-shaped patterns or aperture patterns formed at equal pitch intervals in a resonance region in which a lower electrode and an upper electrode face each other across a piezoelectric film, and a pitch interval of the island-shaped patterns or the aperture patterns in the additional film included in one of the at least two resonators differs from a pitch interval of the island-shaped patterns or the aperture patterns in the additional film included in another one of the at least two resonators.

Abstract: A single-die multi-FBAR (film bulk acoustic resonator) device includes multiple FBARs having different resonant frequencies formed over a single substrate. The FBARs include piezoelectric layers having different thicknesses but with upper electrodes formed at a same height over the substrate, lower electrodes at different heights over the substrate, and different sized air gaps separating the lower electrodes from the substrate.

Abstract: A ribbon comprises a substrate, and a plurality of seals on the substrate. Different seals detune in response to differing tensile loads. At least one of the seals comprises a surface acoustic wave (SAW) radio frequency identification (RFID) seal.

Abstract: In an elastic wave device, an interdigital transducer (IDT) electrode is disposed on a piezoelectric substrate. In at least one of first and second electrode fingers of the IDT electrode, elongated sections with a widthwise dimension larger than that of a center of the first and second electrode fingers in a longitudinal direction are provided in at least one of a portion closer to a base end of the first or second electrode finger and a portion closer to a leading end of the first or second electrode finger than a central region of the first or second electrode finger. At least one of first and second busbars includes a plurality of openings provided separately from each other along the longitudinal direction of the first and second busbars.

Abstract: A bulk acoustic wave resonator may include: a piezoelectric layer including a piezoelectric material; a first electrode disposed on one surface of the piezoelectric layer; a second electrode disposed on the another surface of the piezoelectric layer; and a frame disposed on the one surface of the piezoelectric layer and surrounding the first electrode, wherein the frame is spaced apart from the first electrode by a predetermined gap.

Abstract: An apparatus includes a moving mass transducer. The moving mass transducer generates sound by displacement of a surface defined by a piezoelectric element. The piezoelectric element is displaced in response to an interaction of a first signal with a magnetic field. The piezoelectric element is configured to be separately driving by a second signal.

Abstract: The dominant frequency of a solidly mounted resonator (100/280/300/400) is substantially increased by reducing the thickness of each layer of each Bragg acoustic reflector (112/160/224/274) to have a thickness than is substantially equal to one-quarter of the wavelength of a frequency that is a higher harmonic resonant frequency of the fundamental resonant frequency of the solidly mounted resonator (100/280/300/400).

Abstract: An environmental measurement apparatus includes an operation unit which calculates a first change in a first oscillation frequency of a first QCM sensor and a second change in a second oscillation frequency of a second QCM sensor. The operation unit corrects the second change based on the first change in a first period and the second change in the first period.

Abstract: A vibrating diaphragm includes a diaphragm body and a suspension edge. The diaphragm body is made by acrylonitrile butadiene styrene materials. A surface of the diaphragm body is electroplated a layer of nanoscale materials. The suspension edge is made by room temperature vulcanized silicone rubber materials. The suspension edge is molded an outer periphery of the diaphragm body. The vibrating diaphragm can improve the high frequency effect of the speaker.

Abstract: To improve durability against impact, a quartz crystal resonator element includes a recess in a plan view. The quartz crystal resonator element further includes a first principal surface and a second principal surface that are front and rear surfaces facing away from each other and a side surface disposed between the first principal surface and the second principal surface, and the side surface is formed of flat surfaces and curved surfaces formed by dry etching and alternately arranged. The quartz crystal resonator element preferably has a base and at least one resonating arm extending from the base.