Abstract: The present disclosure relates to bendable and/or foldable articles and uses thereof and to a method of providing bendable and/or foldable articles. The articles are of translucent and brittle material, such as glass, glass ceramic, ceramic or crystals. The articles may be used as a display cover such as a protecting cover in displays in, for example, smartphones, tablet computers, or TV devices. The articles may also be used as a substrate for electronic components, such as OLEDs or LEDs.

Abstract: A method of monitoring usage of a component of an aircraft can include: monitoring a usage of the component by using a torque measurement system to calculate torque events in a time period; categorizing the usage of the component by assigning a usage value based upon whether the number of torque events in the period of time is above or below a threshold; and determining a life used of the component.

Abstract: A method for evaluating local buckling performance of a steel pipe includes obtaining a stress-strain relationship of a material having a yield plateau in the stress-strain relationship; determining the comparison of a starting strain of strain-hardening in the stress-strain relationship obtained and a critical strain of the steel pipe; and evaluating that the steel pipe has a possibility of being applied to a structure that requires plastic design when the critical strain is determined to be larger than the starting strain and evaluating that the steel pipe has no possibility of being applied to a structure that requires plastic design when the critical strain is determined to be not larger than the starting strain.

Abstract: The present invention defines a strain sensor for measuring strains induced on a component surface (34). The strain sensor comprises a strain gauge (31) and a support member (32), whereby the support member is attached to the component surface only at first and second attachment places. The support member comprises a beam portion (39) that is adapted to bend in response to a relative displacement of the first and second attachment places, and the strain gauge is integrated on a surface (33) of this beam portion. To ensure a strong and stable bending response of the beam portion, the attached support member comprises at least one flexure hinge (45).

Abstract: A method and a device are described for compensation of mechanical stresses in an aircraft structure. The method comprises the steps of producing signals that represent mechanical stresses occurring in the aircraft structure, and operating actuators, which absorb at least some of the mechanical stresses and are arranged in the aircraft structure, such that the mechanical stresses are compensated.

Abstract: A method for evaluating local buckling performance of a steel pipe includes obtaining a stress-strain relationship of a material having a yield plateau in the stress-strain relationship; determining the comparison of a starting strain of strain-hardening in the stress-strain relationship obtained and a critical strain of the steel pipe; and evaluating that the steel pipe has a possibility of being applied to a structure that requires plastic design when the critical strain is determined to be larger than the starting strain and evaluating that the steel pipe has no possibility of being applied to a structure that requires plastic design when the critical strain is determined to be not larger than the starting strain.

Abstract: A measuring device is provided for a motor vehicle, with a bracket (1), with a joint (8), which is connected to the bracket (1) and which has a joint housing (20) and a pivot pin (19) mounted movably in same. A component (2) is provided which is connected to the joint (8) and which is mounted pivotably on the bracket (1) via the joint (8). An angle measuring device (17, 18) is provided, by which the angle (?) of the component (2) in relation to the bracket (1) can be determined. An analyzer (23) is connected to the angle measuring device (17, 18) and has a double differentiator (24), which is connected to the angle measuring device (17, 18) and which is followed downstream by a summer or integrator (26) via the intermediary of a calculating unit (25).

Abstract: Modeling and simulation of free and forced structural vibrations is essential to an overall structural health monitoring capability. In the various embodiments, a first principles finite-difference approach is adopted in modeling a structural subsystem such as a mechanical gear by solving elastodynamic equations in generalized curvilinear coordinates. Such a capability to generate a dynamic structural response is widely applicable in a variety of structural health monitoring systems. This capability (1) will lead to an understanding of the dynamic behavior of a structural system and hence its improved design, (2) will generate a sufficiently large space of normal and damage solutions that can be used by machine learning algorithms to detect anomalous system behavior and achieve a system design optimization and (3) will lead to an optimal sensor placement strategy, based on the identification of local stress maxima all over the domain.

Abstract: A method is disclosed of using external polymeric analytical techniques to predict in-vivo polymeric performance, more particularly, viscoelastic property characterization for performance modeling of biomedical devices that incorporate a polymeric component and are load-bearing during service. Time-Temperature Superposition can be used to accelerate external testing of pertinent properties. Boltzmann's superposition provides a mathematical methodology for determining the time-dependent strain that develops in response to an imposed stress history. The modeling of the present invention provides an opportunity to describe and predict behavior of the device during in-vivo service, as well as it providing a basis for evaluating alternate “candidate” polymers for use in the construction of the device.

Abstract: A wireless, non-powered fatigue monitoring sensor uses a piezoelectric element that is attached to the surface of or embedded within a structure to be monitored. When subjected to stress over time, the material properties of the element change reliably and permanently. These properties are used to determine the fatigue history of the structure. The monitoring device requires no power for monitoring and is nondestructively queried to determine the stress history using wireless means such as radio frequency technology.

Abstract: A rock bolt includes a hollow body and a gap along a length of the hollow body. At least one strain gauge is affixed to an inner surface of the rock bolt and is accessible from the gap. The rock bolt may include a data logger within the hollow body and coupled to receive signals from one or more strain gauges, and to record these signals in a memory. The data logger may comprise a data port adapted to be accessible from the outside of a bore hole into which the rock bolt is inserted. The data logger also may include at least one of a visual and auditory alarm. A graphic user interface software program can be used to download data from the data logger and set certain operating parameters of the data logger.

Abstract: A method is disclosed of using external polymeric analytical techniques to predict in-vivo polymeric performance, more particularly, viscoelastic property characterization for performance modeling of biomedical devices that incorporate a polymeric component and are load-bearing during service. Time-Temperature Superposition can be used to accelerate external testing of pertinent properties. Boltzmann's superposition provides a mathematical methodology for determining the time-dependent strain that develops in response to an imposed stress history. The modeling of the present invention provides an opportunity to describe and predict behavior of the device during in-vivo service, as well as it providing a basis for evaluating alternate “candidate” polymers for use in the construction of the device.

Abstract: A system remotely collects test data from a test platform using platform attached sensors. Identification chips, each having a unique identification code, are each paired with an associated sensor to form sensor/chip pairs. At least one patch panel having a plurality of connections is positioned approximate to the platform. Connections are communicatively linked to each of the sensor/chip pairs. A computer system is communicatively linked to additional patch panel connections. The identification of selected sensors is queried by a computer command to the patch panels, and a group of sensors for a given test is identified and selected. Test data from each of the selected sensors is transferred through the patch panels to the computer system for collation and generation of a test setup compatible with a data acquisition system. Test setup information is downloaded to the data acquisition system in preparation for the next test.

Abstract: A method and system for selecting a critical plane. The critical plane can then be used to leverage off of uniaxial fatigue theory to predict the fatigue life of an object experiencing multiple stress inducing events. The fatigue life is based on calculating a single critical plane that encompasses all the stress inducing events.

Abstract: A method is provided for performing wedge analysis for assessing wedge occurrence and instability in underground openings, such as mines, caves, and the like. The method scales full-span wedge predictions, accounting for both occurrence and instability potential of possible wedge geometries. The method also generates predictions for wedge failure potential and support demand to result in more economical support design for wedges.

Abstract: A method for determining the sensitivity of the fatigue life of a structural component with respect to specific design parameters includes obtaining the stress profile for a structural component under random process establishing a relationship between the stress profile and the fatigue life of the structural component, developing the sensitivity of the fatigue life with respect to design parameters, optimizing the design of the structural component based upon the design parameters to which the fatigue life is most sensitive.

Abstract: An electronic stress monitoring device (1) is provided that is arranged to detect and record measurements of stress experienced by a structure (2) to which the stress history unit is attached, with the measurement and recordal of stress occurring at substantially the same location. The stress monitoring unit (1) is also arranged to process the detected readings of stress to determine when significant structural events are occurring within the structure (2) to which it is attached. Data indicative of these events are recorded within the stress monitoring device (1). Periodically data recorded within the stress monitoring device (1) is obtained by a data reader (4) and then transmitted to a computer (6) for subsequent analysis.

Abstract: The invention relates to a service life indicator for monitoring structures, such as pioneering bridges, which are designed with a limited fatigue strength and whose service life is therefore limited. A service life indicator for monitoring structures, such as pioneering bridges designed with a limited fatigue strength and consequently limited service life, is provided. The service life indicator includes a strip of material as a test piece, having at least one hole arranged off-center in the test piece and a notch extending from an edge of the hole in a direction of an edge of the test piece for determining material fatigue. The notch extends to a nearest edge of the test piece and includes two mutually opposite grooves having the same cross-sectional shape that can be one of round, elliptical, oval, v-shaped and trapezoidal in cross-section.

Abstract: An apparatus for accurately locating a micro-electronic chip in a chip-holding cavity for visual testing, the chip having at least a front wall and a pair of opposed, spaced-apart side walls, wherein the front wall meets with each of the side walls to form opposed, spaced-apart first and second front edges, comprising a cavity side wall formed to juxtapositionally abut at least one of the side walls of the chip, the cavity side wall having formed therein a depression creating a shadow projecting forward from the depression, wherein the first front edge of the chip forms a border of the shadow to form an objectively measurable contrast in grayness between the shadow and the chip.

Abstract: Apparatus for providing support to, and/or measuring the stress present in a potentially unstable structure, such as the roof of a coal or other underground mine, or a rock mass. The apparatus is an instrumented cable that has a center wire having a plurality of stress measuring devices attached along its length. Forming material is placed around the center wire and the stress measuring devices in order to provide protection and support. A plurality of noncenter wires extend generally longitudinally around the center wire, the stress measuring devices, and the forming material. Advantageously, the apparatus measures the stress placed thereon when inserted into the potentially unstable structure at more than one location along the length thereof, may be spun into a rock mass without damaging the stress measuring devices (or other components of the apparatus) and may be grouted into the potentially unstable structure with a variety of different grouts.

Abstract: In one embodiment of the invention, a pressure sensor array, data acquisition circuit, and a microprocessor are mounted in a hand held pad. Detection of nodules is achieved by analyzing the dynamic and spatial features of the pressure pattern while the probe pressed to the breast is periodically moved transversely to the ribs. The ribs play a role as an amplifier of the measured effect. The device will be able to objectively detect the presence of lumps in a breast and provide a warning signal. Another embodiment of the invention is a clinical device for imaging the mechanical structure of the examined breast and diagnosing diseases accompanied by changes in the elasticity of breast tissue. This embodiment is made up of an electronically controlled mechanical scanning unit incorporated into a patient support bed. The mechanical scanning unit includes a compression mechanism and positioning system, a local pressure source located opposite a pressure sensor array, and electronic control and interface circuitry.

Abstract: A method and a device for noninvasively identifying a region of the tissue having a different elasticity than the surrounding tissue by simultaneously measuring strain and stress patterns in the tissue portion using an ultrasonic imaging system combined with a pressure sensing array. In a particular embodiment, a pressure sensing array made of a sound transparent film inserted between the ultrasonic scanner probe and the tissue measures pressure pattern on the surface of the tissue when the tissue portion is deformed while the scanner detects internal strain pattern. The ultrasonic scanner probe with the attached pressure sensing array serves as a pressure exerting member causing a deformation of the tissue and creating stress and strain in the tissue portion.

Abstract: An apparatus for monitoring the fatigue strength of a structure comprises a longitudinal rib which is attached or integrated to the surface of the structure. The rib has a plurality of transverse notches of differing depths, each of the notches having a rounded end adjacent the surface of the structure and a pointed end extending toward an exterior edge of the rib.

Abstract: An apparatus and method for imaging a portion of the body tissue comprises support for a portion of the tissue, and a force applying member that tends to deform the tissue relative to a reference position, while at the same time a pressure pattern distribution is generated indicating areas of greater pressure which are a function of the amount of deformation and localized portions of the tissue being deformed.

Abstract: A device for monitoring the fatigue life of a structural member composed of a predetermined material, and a method of making same. The device is a substantially flat fuse composed of a material similar to the predetermined material and mountable on a structural member by adhesive during use. The fuse has cut out portions which define fuse elements and variable unbonded areas are formed about the fuse elements to effect failure at different times in sequence because of fatigue and prior to the failure of the monitored structural member when the fuse and the monitored structural member are subjected to substantially the same stress history.

Abstract: An apparatus and method for force-controlled fatigue testing of a specimen or material. A driver is used to generate a load force which is applied to the test specimen. Physical property changes of the test specimen are measured over time and a feedback signal is generated as a function of the measured physical property changes. A motion command signal is computed as a function of the feedback signal. A computer processes the feedback signal and emits the motion command signal to an actuator. The driver responds to the motion command signal and maintains the load force at an approximately constant magnitude during the physical property changes of the test specimen.

Abstract: A strain or stress gauge 1A is presented for measuring the stress of a structure or a member. The gauge 1A comprises a bundle of electric conductive fibers 3, and a pair of terminals 4, for measuring an electric resistance of the bundle of electric conductive fibers provided on both ends thereof. It presents a strain or stress gauge having a simple structure, which can be produced inexpensively, and its size can be chosen freely. It is possible to know not only the state of a strain or stress but also the history of stress in a structure or a structural member which, by the characteristics of a specific curve relating the stress/strain relationship of the gauge.

Abstract: The present invention is intended to facilitate prediction of the life of a structure, such as a frame of a dump truck and so forth without requiring cumbersome calculations. A gauge (2, 3 or 4) for predicting a life of a structure comprises a gauge main body of a thin plate form having annular ring portions (5, 6) of substantially the same configuration at both ends and a strip-like connecting portion (7) integrally connecting the annular ring portions and formed with V-shaped cut-outs (8, 8) at the intermediate portion in opposition to each other. The gauge main body has a shorter life than the life of the structure (1) to be predicted. A crack gauge is fitted between the mutually opposing cut-outs. The gauge is fixed on a predetermined position on the structure by way of welding or so forth. A breaking time of the gauge can be obtained from a variation of a measured resistance of the crack gauge. Based on the breaking period, the life of the structure (1) is predicted.

Abstract: A device for monitoring the fatigue life of a structural member composed of a predetermined material, and a method of making same. The device is a substantially flat fuse composed of a material similar to the predetermined material and mountable on a structural member during use. The fuse has cut out portions which define fuse elements which also have reduced thicknesses to effect failure at different times in sequence because of fatigue and prior to the failure of the monitored structural member when the fuse and the monitored structural member are subjected to substantially the same stress history.

Abstract: A thermally stable fixture for testing asphalt samples is characterized by easurements of both thermal stresses and strains in the sample. The device uses air as the sample cooling or heating fluid for inducing thermal stresses and strains therein. Strains are detected by a linear variable differential transformer mounted on the sample suspended within the fixture. Stresses are detected by a load cell connected with a mounting plate for the sample. Temperatures are detected by temperature sensors attached to the sample and to the fixture for measuring sample and ambient air temperatures, respectively.

Abstract: A method of evaluating residual life of a heat-resistant steel member after and during service at high temperature and stress makes use of a residual life evaluation diagram which is obtained beforehand on a plurality of samples of the heat-resistant steel and which represents the relationship between the life consumption and a parameter which indicates the life consumed. The parameter may be data concerning the density of an alloy element such as molybdenum and chromium, or the state of degradation in the metallurgical structure and/or state of precipitation of carbides.

Abstract: Apparatus and method for automatically measuring the interior dimensions of tunnels. The apparatus is mounted on an inspection vehicle and comprises a plurality of ultrasonic transducers which are arranged to form an imaginary template a predetermined distance from the tunnel wall. The transducers are periodically operated by a computer to derive measurement information as the inspection vehicle moves through the tunnel. The results of each measurement are stored by the computer for subsequent analysis.

Abstract: Disclosed is a method of predicting the remaining lifetime of a metal material, wherein the shapes of grains of the metal material are quantitatively measured to obtain variations in the shapes of the grains, and the remaining lifetime of the metal material is predicted on the basis of the variations. In accordance with the present invention, it is possible to statistically arrange the variations in the shapes of the grains by measuring such variations sequentially in time.

Abstract: A device which is circumferentially affixed to a flaccid penis about the proximal portion of the shaft thereof prior to retiring at night. The device is in the form of a band of material which includes an expandable portion which will not retract once expanded. In the event of a nocturnal erection, the device will expand in response to circumferential enlargement of the penis which occurs during the erection. The expanded device is retrieved upon arising in the morning and is dispatched to one's physician for analysis.

Abstract: Previous methods for determining internal stress in polycrystalline solids by X-ray diffraction techniques have required that the distance between the X-ray irradiated surface of the sample under investigation and the X-ray detection surface for the diffracted X-rays be known. According to the practice of this invention, stress measurement can be made without determining the sample to detector distance as a separate step. Two or more sets of detection surfaces, i.e., X-ray detector channels, are arranged around the incident X-ray beam, usually on opposite sides of the cone of diffracted X-rays from one another. The invention employs a calibration procedure which provides a set of calibration parameters, which, when used with X-ray stress equations, yields accurate internal stress measurement without the prior art requirement of determining the sample to detector distance.

Abstract: Electrical signals, representative of stress induced in a structure, are developed by a piezoelectric transducer (10) attached to the structure in response to stress changes in the structure caused by loads applied to the structure. The signals storage signals from the electrical signals and the storage are processed by a signal processing circuit (12) to develop signals are accumulated by a storage unit (14) to develop a fatigue condition indication of the cumulative effect of the loads applied to the structure.

Abstract: A device for monitoring the fatigue life of a structural member is comprised of at least one and preferably a plurality of substantially flat, elongated coupons which are fabricated of the same material as that of the member being monitored. The coupons are secured in parallel to the member so that they all experience the same strain history as the member. Each of the coupons includes a different stress concentrating notch pattern so that the application of the same strain to all of the coupons results in the development of different stress concentrations within the coupons. The development of different stress concentrations within the coupons causes each coupon to have a different fatigue life, the fatigue life of each coupon being a predetermined percentage of the fatigue life of the structural member being monitored.

Abstract: The invention relates to a fatigue indicator for mechanical parts subjected to repeated stresses, which comprises two thick elements spaced apart from one another and joined together by a thin web having a slit, these two elements being incorporated in the part or fixed thereto so as to move with respect to one another upon application of stress on the mechanical part in a plane which is parallel to the plane of the web, the thin web being thus subjected to a shearing stress in its plane, and wherein the slit of the thin web extends from one of the edges of the web in the direction of relative movement to a blind end so that, when the part is stressed, two cracks appear from corners of the blind end of the slit, extend progressively in the web and finish by reaching the opposite edge of the web or joining cracks coming from this opposite edge, the web thus being detached or practically detached.

Abstract: The present invention relates to an improved fatigue damage indicator for a echanical member subjected to repetitive stress, comprising two thick elements which are spaced from one another and are connected one to the other by a thin web or plate formed with a slot and at least one pair of free opposite edges, the two elements being so connected with the mechanical member or fixed to the latter so that they are displaceable relative to one another in a plane parallel to the plane of the thin plate, the thick elements being disposed so as to be separated from one another in a direction substantially perpendicular to their direction of relative displacement by such stress, the thin plate being placed under shear force in its plane by such relative displacement, the slot of the thin plate extending from one of the edges of the web in the said direction and terminating short of the opposite edge in a blind end of the slot having two corners so that, with application of stress, two cracks develop at corners of the

Abstract: Strain gauges are attached to a drill pipe which is inserted into a drill pipe string to be used in a well. The strain gauges are connected to an electrical circuit containing devices for digitizing the electrical signals generated by the strain gauges in response to the detection of strain and for recording and retaining the digitized signals until the drill pipe string is extracted from the well. The electrical circuit provides a communication path through which the stored digitized data is transferred to an external device when the drill pipe string is extracted from the well.

Abstract: A fatigue cycle sensor can integrate force with respect to time. The sensor has a body with a bore. A plunger is mounted in the bore for relative motion therethrough in response to force applied behind the plunger. The plunger is sized for an interference fit in the bore. This interference fit results in deformation in response to relative motion between the plunger and body. The foregoing sensor has many applications including estimating fatigue in weapons.

Abstract: The number of steps taken while walking are counted by straining a fatigue life gauge to change its electrical resistance each time the device is stepped on by a subject. The change in resistance of the fatigue life gauge is measured to ascertain the approximate number of steps taken.