An anchoring device, in particular to a bolt anchor or an expansion anchor, includes a communication interface via which at least one item of information can be made available to an external device. It is proposed that the communication interface have at least one surface wave unit for generating an acoustic surface wave.

A portable inspecting device includes PZT transducers and performs active sensing to measure the characteristics of bolted connections. The PZT transducers are mounted on opposing ends of spring-loaded rods and can be moved apart to accommodate a structure for testing. The springs cause the PZT transducers to push against opposing parts of the structure in a stable but temporary fashion. The device can be physically moved to inspect the status and health of multiple different bolted connections.

Provided is a method for setting bottom-touching-determination standard capable of setting a bottom-touching-determination standard based on parameters with high reliability. The method for setting bottom-touching-determination standard includes a screwing step of screwing a measurement screw (11) into a measurement screw hole (13a), a parameter acquisition step of acquiring parameters in the screwing step, a bottom-touching-determination step of determining the presence or absence of bottom-touching on the basis of an axial force of the measurement screw, and a determination standard setting step of collating the determination result in the bottom-touching-determination step and the parameters to set the bottom-touching-determination standard.

A device for inspecting clamping means, including an electromagnetic ultrasonic transducer including a winding for generating pulsed eddy currents on the surface of a clamping element, built into a system for generating a magnetic field including a cylindrical magnet arranged above the winding with the axis of rotation thereof coinciding with the axis of the winding and a magnetic circuit surrounding the magnet and the winding to guide the generated magnetic field so that the field lines pass obliquely towards the axis of the coil through an interface plane with the clamping element, opposite the winding, the interaction of the field lines and pulsed eddy currents being suitable for simultaneously generating longitudinal and transverse ultrasonic waves in the clamping element.

A system, probe and method accurately measure the strain or extension of a fastener that occurs as a nut on the fastener is tightened and the fastener is put under load. The measurement technique is based on measurement of the time for an ultrasonic wave generated on one end of the fastener to travel a round trip through the fastener. As the fastener is tightened, the applied stress causes an associated increase in length. This length can be determined from a measurement of the increase in transit time. In various embodiments, the disclosed device and method uses laser ultrasonic testing (LUT), in which a pulsed laser generates the ultrasonic wave and a type of laser vibrometer detects the wave when it returns to the position of generation following a combination of longitudinal and shear wave reflections, which result in a higher magnitude and more easily and precisely measurable reflected signal peak than a signal peak associated with a signal directly reflected against the opposite end of the fastener.

The present invention discloses a piezoelectric patch-based real-time and high-precision bolt preload detection method and system. A piezoelectric patch is used as an ultrasonic excitation source and pasted on the head of a bolt, and the high-precision fitting relationship between the ultrasonic change of time-of-flight and the bolt preload is established according to the law of the ultrasonic change of time-of-flight of single echo with the stress so that the real-time detection of the bolt preload is realized by using the mathematical relationship. Compared with the previous method using ultrasonic probes, the present invention eliminates the error caused by the uncertainty of couplant thickness and further improves the measurement precision by using the change of time-of-flight of single echo. Meanwhile, the low-error rate measurement of the bolt preload is realized at a low cost and without affecting the structural performance.

The systems and methods described herein are for monitoring the tightness of bolts. The systems and methods may be used with a mechanism to apply a percussive tap and with a recording or monitoring device for detecting and recording the acoustic signals that are generated by the percussive tap. The acoustic signals generated by percussive taps applied to bolts in various looseness states are analyzed and a machine learning model is developed that allows for determining bolt looseness based on the acoustic signals.

An axial force measurement apparatus measuring an axial force of a bolt member by measuring a clamping force, of a nut member threaded onto the bolt member, which is applied to fasten a structure, includes: a sensor that applies vibration to the structure through one side of the tightened nut member and obtains, on an opposite side of the nut member, a signal by the vibration that propagates through the structure and passes through the nut member; and an analyzer that analyzes the signal received from the sensor and determines the axial force of the bolt member using a difference in propagation velocity of the signal by the vibration according to the clamping force of the nut member.

Fixing device comprising a fixing member provided with a bearing head, a sensor provided with a detector of the mechanical force to which the fixing member is subjected, the detector being mounted in contact with the fixing member, and a connecting component which is electrically connected to the sensor, which is configured to transmit a measurement of a mechanical force provided by the sensor and which is mounted on the fixing member, the fixing member comprising a body which is mounted on the bearing head and which extends along a longitudinal axis protruding from the bearing head.

Exemplary embodiments are directed to instrumented fasteners and associated damage detection systems for detecting damage in an assembled structure secured together by at least one instrumented fastener. The instrumented fastener forms a transducer assembly for detecting damage in the assembled structure. The fastener can include a cavity disposed at one end of the fastener. The transducer assembly includes an electromechanical unit at least partially inserted into and mechanically coupled within the cavity of the fastener. The electromechanical unit can include a piezoelectric element.