2705results about "Material strength using repeated/pulsating forces" patented technology

An in-plane shear and multi-axial tension or compression testing apparatus having four-bar linkages pivotable to two sleeves on an opposite vertices with the sleeves of each vertex rotationally attached to each other. Lateral links of each linkage are pivotally attached to load transfer plates in which the plates secure a test specimen. Each linkage is rotatable to the other linkages while the vertices are subjected to a compression or tensile load. The vertices are also capable of rotation by a testing machine for shear testing. During compression or tension of the vertices of the apparatus, the plates respectfully move toward or away from each other thereby applying compression or tension to the specimen. The bars of one linkage can be rotated with respect to the other, thereby applying torsional loading to the specimen.

Disclosed herein is a robot mechanism for inspection of a live-line suspension insulator string. A robot body of the robot mechanism reciprocates along the live-line suspension insulator string and includes upper and lower robot frames configured to encircle the insulator string, a battery module provided to either end of the robot body, an actuation module for moving the robot body along the insulator string, an inspection module for electrically inspecting an insulator, a connection module for coupling the robot body to an installation/dismantlement mechanism, a wing opening/closing module for manually separating the robot body from the insulator string, a measurement module for measuring electrical properties of the insulator, a controller for controlling operation of the robot body, and a crack detection unit for detecting cracks formed in the insulator.

A method and apparatus for testing a football helmet utilizes a weighted pendulum arm to impart an impact force upon the helmet. Linear head acceleration and rotational head acceleration caused by the impact force is measured and a Head Impact Power Index is computed and used as a standard to judge the ability and effectiveness of the football helmet in preventing injury to a football player.

A method of constructing a sensor includes depositing a first material in a predetermined arrangement to form a structure. The depositing results in at least one void occurring within the structure. The method further includes depositing a second material within the voids. The second material may have electrical properties that vary according to deformation of the second material. The method also includes providing electrical access to the second material to enable observation of the one or more electrical properties. A sensor includes a structure that has one or more voids distributed within the structure. The sensor also includes a material deposited within the one or more voids. The material may be characterized by one or more electrical properties such as piezoresistivity. The sensor includes a first contact electrically coupled to a first location on the material, and a second contact electrically coupled to a second location on the material.

An apparatus (10) for applying at least one load to a specimen (12) according to one embodiment of the invention may comprise a mass (18). An actuator (20) mounted to the specimen (12) and operatively associated with the mass (18) moves the mass (18) along a linear displacement path (22) that is perpendicular to a longitudinal axis of the specimen (12). A control system (26) operatively associated with the actuator (20) operates the actuator (20) to reciprocate the mass (18) along the linear displacement path (22) at a reciprocating frequency, the reciprocating frequency being about equal to a resonance frequency of the specimen (12) in a test configuration.

Systems, apparatuses and methods are described for integrating an electronic metrology sensor with precision production equipment such as computer numerically controlled (CNC) machines. For example, a laser distance measuring sensor is used. Measurements are taken at a relatively high sample rate and converted into a format compatible with other data generated or accepted by the CNC machine. Measurements from the sensor are synchronized with the position of the arm of the machine such as through the use of offsets. Processing yields a detailed and highly accurate three-dimensional map of a workpiece in the machine. Applicable metrology instruments include other near continuously reading non-destructive characterization instruments such as contact and non-contact dimensional, eddy current, ultra-sound, and X-Ray Fluorescence (XRF) sensors. Various uses of measurements include: multiple component matching, correction of machine drift, closed loop control of machines, and verification of product tolerances via substantially complete serialized dimensional quality control.

An acoustic energy-based, non-contact or contact testing approach provides low cost, highly accurate, and reliable information to (a) identify flaws and anomalies and (b) assess the integrity of a particular material. This approach is not hindered by surface conditions or impediments, and indeed, looks beneath the surface of the material by propagating an acoustic wave through the material using two differential transducers. A dynamic differential measurement is made of the material under a load condition and an unloaded condition that allows identification and assessment of various characteristics of the material. Multiple “windows” of information may be generated that permit (a) direct detection of flaws, defects, and anomalies using a scattering technique, (b) detection of crack closure and opening used to assess the stability of the material, (c) determination of strain on the material which relates to its performance, and (d) determination of defect dynamics linked to the defect size and stability.

A helmet includes a head enclosure with an open cavity for the head of a user and a shock detector attached to the head enclosure that provides a signal when the head enclosure is subjected an impact exceeding a predetermined level.

The invention relates to a method for determining accumulated body fatigue index (BFI), wherein one or more parameters from the measurement of one or more signals are obtained sequentially as input and these parameters are information on the intensity of physical activity. BFI has a predetermined initial value, and next BFI value is always a sum of BFI-value and a difference. The difference is combination of upslope and optional downslope components of BFI determined with the said parameters and the upslope component and the optional downslope component are each determined with a function, which is scaled by a preset physiological character.

A measurement device is provided that determines fluid properties from vibration frequencies of a sample cavity. In one embodiment, the measurement device includes a sample flow tube, vibration source and detector mounted on the tube, and a measurement module. The sample flow tube receives a flow of sample fluid for characterization. The measurement module employs the vibration sources to generate vibrations in the tube. The measurement module combines the signals from the vibration detector on the tube to determine properties of the sample fluid, such as density, viscosity, compressibility, water fraction, and bubble size. The measurement module may further detect certain flow patterns such as slug flow, for example. To measure the sample fluid density, the measurement module determines the resonant frequency of the sample flow tube. The density can then be calculated according to a formula that compensates for the temperature and pressure of the system.

An apparatus and method for determining the kinematic characteristics of a golf club head are disclosed. The apparatus includes at least one piezoelectric component selectively positioned within or upon a club head. The piezoelectric component is preferably positioned to the rear of the center of gravity, and near the midpoint of the face of the club head. During a golf club swing, the piezoelectric component determines the acceleration and deceleration of the golf club head. When the club head impacts an object such as a golf ball, the piezoelectric component is also operable to determine the velocity of the club head. It may also be desirable for the piezoelectric component to determine the magnitude of vibration during impact. In this manner, the piezoelectric component may function determine the efficiency of a golf club swing.

Acoustic sensing utilizing a cantilever structure coupled about at least one side of said cantilever to a base substrate, wherein said cantilever includes a piezoelectric section and has at least one acoustic wave device on a portion of the cantilever, wherein a flexure of the cantilever produces force-frequency effects measurable by the acoustic wave device. According to one embodiment, the cantilever sensor uses the flexure-frequency effect as measured by an acoustic wave device to sense a target matter. According to one embodiment, a sensing material is disposed on at least a portion of at least one surface of the cantilever.

A sensor senses an environmental condition. The sensor includes a film bulk acoustic resonator that includes a layer of material that causes resonant frequency and/or quality factor shifts of the film bulk acoustic resonator in response to changes in the environmental condition. The environmental condition may be relative humidity and the layer of material may be a moisture absorptive material.

The invention relates to a large contact surface characteristic direct shear apparatus with cycle loading function, in particular to a novel large direct shear apparatus for researching the interface frictional characteristics between soils, between geo-synthetic and soil or between geo-synthetics, wherein the apparatus is applied for the equal shear surface test or variable shear surface test between optional two materials, and the direct shear apparatus is particularly applied for performing the interface characteristic test research under the functions of vertical cycle loading and horizontal cycle loading.

The invention provides a natural gas hydrate deposit dynamic triaxial mechanic-acoustic-electrical synchronous test experimental device, and a test method. The natural gas hydrate deposit dynamic triaxial mechanic-acoustic-electrical synchronous test experimental device comprises an acoustic wave receiving device, an acoustic wave transmitting device, and a resistivity testing device. The natural gas hydrate deposit dynamic triaxial mechanic-acoustic-electrical synchronous test experiment method comprises the steps that: step A, a hydrate sample is synthesized; step B, the synthesized hydrate sample is subjected to dynamic loading, and electric-acoustic-mechanical property tests are simultaneously carried out, until the sample is subjected to shearing damage. The invention provides a mechanical response characteristic research of indoor hydrate deposit under dynamic load. With the device and the method, mechanical, electrical, and acoustic parameter synchronous testing of hydrate deposit under dynamic load can be realized. With the test data, a relationship between mechanical parameters and wave velocity can be obtained by fitting.

An acoustic-based system, such as a touchscreen system, is provided. The system comprises an acoustic substrate and an acoustic transducer operably coupled to the substrate. The transducer exhibits a higher order odd resonant frequency that is equal to the operating frequency of the system. As a result of using the higher resonant frequency that is substantially equal to the operating frequency, the thickness of the transducer can be increased, and thus made more durable.

A turbine disc/blade tenon connection high-temperature combined fatigue loading device comprises a low cycle load stress application mechanism, a force transmission pin, a force transmission main tension plate, a force transmission crown plate, a force transmission round bar, a blade clamp, a rolling bearing, a hold-down bolt, a high cycle transmission plate, a high-frequency heating cycle, and a vibration generator, wherein, the low cycle load stress application mechanism is connected with the force transmission main tension plate through the force transmission pin; the force transmission main tension plate is connected with the force transmission round bar through the rolling bearing; the lower end of the force transmission crown plate is sleeved on the force transmission round bar, and the upper end is connected with the load bearing dummy club of the blade clamp through the rolling bearing; the blade clamp is connected with the blade of a turbine through the hold-down bolt; the turbine disc is connected with the low cycle load stress application mechanism through the force transmission pin; the high cycle transmission plate is connected with the blade clamp through the hold-down bolt; and the vibration generator is positioned on one side above a high cycle load transmission plate. The loading method is characterized in that the force application point of low cycle loads is moved backwards, thereby enabling small high cycle loads to be smoothly transferred to the tenon connection position, ensuring the stress distribution along the tenon tooth is reasonable, and preventing combined loads from interfering with each other.

In a method for monitoring the condition of a mechanical seal in an apparatus provided with a rotating part, in particular in a pump which has a rotating shaft for the forwarding of a fluid, the sound emission of the seal is continually measured at discrete times in the operating state of the apparatus and at least one statistical characteristic value is won from the acoustic signals. The analog acoustic signals are converted prior to the determination of the statistical characteristic value into analog demodulated signals, the maximum frequency of which is less than about 50 kHz.

A piezoelectric cantilever with a non-piezoelectric, or piezoelectric tip useful as mass and viscosity sensors. The change in the cantilever mass can be accurately quantified by monitoring a resonance frequency shift of the cantilever. For bio-detection, antibodies or other specific receptors of target antigens may be immobilized on the cantilever surface, preferably on the non-piezoelectric tip. For chemical detection, high surface-area selective absorbent materials are coated on the cantilever tip. Binding of the target antigens or analytes to the cantilever surface increases the cantilever mass. Detection of target antigens or analytes is achieved by monitoring the cantilever's resonance frequency and determining the resonance frequency shift that is due to the mass of the adsorbed target antigens on the cantilever surface. The use of a piezoelectric unimorph cantilever allows both electrical actuation and electrical sensing. Incorporating a non-piezoelectric tip (14) enhances the sensitivity of the sensor. In addition, the piezoelectric cantilever can withstand damping in highly viscous liquids and can be used as a viscosity sensor in wide viscosity range.

The invention relates to a material mechanical property in-situ testing system and method in a dynamic and static load spectrum, and belongs to the field of mechanical tests. The system integrates the following functions: a static testing function of biaxial drawing and shearing in an orthogonal plane, a shearing static testing function, a double shaft pull-pull mode fatigue testing function, and a static/dynamic press testing function. A complicated static/dynamic load spectrum can be established. Multi-mode composite load mechanical property evaluation can be performed on a film material or a block material, for example: high-cycle fatigue tests based on double-shaft pre-stretching load and impact press tests based on double-shaft stretching-shearing pre-load. At the same time, special defects are pre-fabricated on the central area and cross shaped arm area of a test piece; the analysis functions of a variable-zoom optical imaging system or a digital speckle strain analysis system can be utilized; the provided system and method can also be used to research the deformation behavior and cracking expansion rules of micro defects in a component under a multi-dimensional stress, and an evaluation tool is provided for performance degradation rules of products and optimized preparation method of materials.

Embodiments include an apparatus and method for testing a particulate material suitable for use as a proppant. According to one embodiment, a sample of the particulate material is captured in the cavity of a test vessel between a cavity wall and a piston sealed with the cavity wall. A fluid is flowed into the test vessel from a fluid inlet of the test vessel to wet the sample of particulate material. The fluid is pressurized to a target fluid pressure greater than ambient pressure and heated to a target temperature greater than ambient temperature. The piston is moved into direct contact with the particulate material with sufficient force to crush at least a portion of the particulate material while maintaining one or both of the target temperature and the target pressure for one or more test cycles. Each test cycle has a duration of at least about 120 seconds and as long as about 24 hours.

An impact detection system provides a means of sensing, monitoring and recording impact events on an impact surface using at least one sensor that is incorporated into the impact surface. The sensor(s) can be integral with, attached to or located behind various types of impact surface including various types of garments that can be worn by an individual or on composite materials such as an aircraft fuselage for example. The impact detection system includes a portable impact detection device electrically connected to the sensor(s) and is used to detect ballistic or non-ballistic type impacts on the impact surface. The portable impact detection device processes the impact data detected by the sensor(s) and stores the data for analysis at a later time or outputs the data to a third party system for review and/or analysis.

This invention relates to a resonant device with detection in the piezo-resistive plane made using surface technologies on a bulk, which comprises a resonator connected to this bulk by at least one embedded portion, means of exciting this resonator and detection means comprising at least one suspended beam type strain gauge made from piezo-resistive material, in which each strain gauge has a common plane with the resonator, and is connected to this resonator at a point situated outside of this at least one embedded portion to increase the stress observed by this strain gauge.

An apparatus and method for determining a parameter of interest of a formation composed of carbonate rock. A nuclear magnetic resonance (NMR) sensor assembly produces a pulsed RF field designed for obtaining measurements indicative of the parameter of interest of the formation. A downhole processor processes the measurements for obtaining BVI and BVM using a cutoff time based on classification of the carbonate. Further processing is done to estimate the permeability of the carbonate.

In a dynamic mechanical analysis, a test specimen (2) is coupled to an excitation device (4) by means of a holder device (3). The excitation device (4) applies an excitation force comprised of a static pre-tensioning force component and a time-variable force component to the test specimen, and a deformation of the test specimen (2) is measured by means of one or more displacement sensors (5). The method includes a test phase with the steps: applying the excitation force to the test specimen; while said excitation force is in effect, determining at least one decision parameter, said decision parameter being indicative of a degree of slack in said coupling of the test specimen; comparing said decision parameter to at least one reference value; based on said comparison, determining whether or not the test specimen is coupled to the excitation device in a completely slack-free state, so that physical values derived from said measurements of the deformation will not be subject to errors caused by an insufficient amount of said pre-tensioning force component.

The invention discloses a method for testing accelerating and loading of main drive wheel type pavement materials and a device thereof. The device comprises a control console, a PLC control box, an electronic box, a hydraulic device, a motor, a brake, a driving chain and chain wheel, a drive wheel, a driven wheel, a water bath tank, a circulated air inlet duct, a thermostatic chamber, a test cabinet and a circulated air outlet duct; the control console is positioned on the outside of the test cabinet; the hydraulic device is connected with the driven wheel; the motor is connected with the drive wheel via the driving chain and chain wheel; the drive wheel is fixed on a bracket; the driven wheel is positioned in a guide slot; the water bath tank is arranged right below the driven wheel; a ranging laser is positioned on one side of the driven wheel; one end of the drive wheel is provided with a microphone and the bottom thereof is provided with a torque sensor; the contact surface of the drive wheel and a test piece is provided with a pressure sensor; two tachometers are fixed on the bracket and are respectively positioned on the outsides of the drive wheel and the driven wheel. The device has simple structure, low prices, flexible use and good reliability.

The invention discloses a general Hopkinson bar device for compression load and stretching load, which aims to integrate compression load and stretching load into an experiment system. The invention has the technical scheme that the general Hopkinson bar device comprises a bidirectional gas emitting thrower and a bar system. The bidirectional gas emitting thrower accelerates a bullet leftwards orrightwards based on experiment requirements and comprises a high pressure gas container, a thrower pipe, a gas inlet control valve, a first gas outlet control valve, a second gas outlet control valve,a first connection pipe, a second connection pipe, a first gas conversion joint, a second gas conversion joint, a columniform or cylindrical bullet, a columniform or cylindrical top plug corresponding to the columniform or cylindrical bullet, and a top needle. The bar system comprises a compression incident bar, a compression transmission bar, a stretching incident bar, a stretching transmissionbar and strain foils. The general Hopkinson bar device overcomes difficulties in respectively creating two sets of independent equipment for a Hopkinson compression bar and a Hopkinson stretching bar,realizes the integration of the Hopkinson compression bar and the Hopkinson stretching bar and can be converted conveniently between the two load modes.

A method and apparatus for improving temperature stability of surface-launched acoustic wave sensors is described. The system includes a plurality of acoustic wave delay lines or resonators coated with identical films which are physically, chemically, biologically, or otherwise sensitive to one or more target chemical or biological analytes. At least one of the delay lines or resonators, referred to herein as reference channels, is used as a frequency reference to which the oscillation frequencies of the remainder of the delay lines or resonators, referred to as sensing channels, are compared. A thin coating of material that is preferably a passivation layer not sensitive to the analytes, is disposed upon the surface-launched acoustic wave sensor. The passivation layer covers sensing films on the reference channels, blocking or impeding interaction of the sensing films and the analytes thereby. The passivation layer is covered by the sensing films on the sensing channels, allowing interaction between the sensing films and the analytes thereby. All reference and sensing channels are preferably configured as oscillators, whereby effects of temperature fluctuation can be reduced significantly through subtractive combination of the reference and sensing channel oscillation frequencies.

Embodiments of a crash simulator sled assembly are disclosed. The crash simulator sled assembly can include a sled, an element movable relative to the sled, and a force element, such as a damper assembly or actuator assembly, coupled to the element. A second sled can also be connected to the element. The damper assembly can control relative movement of the element relative to the sled, while the actuator can develop force to replace force attributable to mass. This provides advantages for more efficient and effective test crash simulation and research.

A sensor network is attached to a structure and employed to detect and analyze load changes. The sensor network has transducers, capable of acting as both passive sensors and active actuators, integrated within it. In a passive mode, the transducers detect load changes upon the structure, such as impacts. Upon detection of a load change, the transducers are engaged in an active mode to actively scan the impact area to determine the location and size of any resulting damage region. In this manner, passive and active systems are integrated within a single, convenient layer that possesses the best features of both active systems and passive systems.