Disclosed is a method for estimating the tension of a tension member (1), the method comprising the steps of exciting the tension member (1) such as to induce vibration of the tension member (1), sampling the vibration to obtain a first vibration signal (VS1), modifying the mass and/or the rotational inertia of the tension member (1) such as to provide a modified tension member (1a), exciting the modified tension member (1a) such as to induce vibration of the modified tension member (1a), sampling the vibration of the modified tension member to obtain a second vibration signal (VS2), and estimating the tension of the tension member based on a comparison of the first vibration signal (VS1) and the second vibration signal (VS2). Disclosed is also a system for estimating the tension of a tension member.

Disclosed is a method for estimating the tension of a tension member (1), the method comprising the steps of exciting the tension member (1) such as to induce vibration of the tension member (1), sampling the vibration to obtain a first vibration signal (VS1), modifying the mass and/or the rotational inertia of the tension member (1) such as to provide a modified tension member (1a), exciting the modified tension member (1a) such as to induce vibration of the modified tension member (1a), sampling the vibration of the modified tension member to obtain a second vibration signal (VS2), and estimating the tension of the tension member based on a comparison of the first vibration signal (VS1) and the second vibration signal (VS2). Disclosed is also a system for estimating the tension of a tension member.

Hundreds of thousands of concrete bridges and hundreds of billions of tons of concrete require characterization with time for corrosion. Accordingly, protocols for rapid testing and improved field characterization systems that automatically triangulate electrical resistivity and half-cell corrosion potential measurements would be beneficial allowing discrete/periodic mapping of a structure to be performed as well as addressing testing for asphalt covered concrete. Further, it is the low frequency impedance of rebar in concrete that correlates to corrosion state but these are normally time consuming vulnerable to noise. Hence, it would be beneficial to provide a means of making low frequency electrical resistivity measurements rapidly. Further, prior art techniques for electrical rebar measurements require electrical connection be made to the rebar which increases measurement complexity/disruption/repair/cost even when no corrosion is identified. Beneficially a method of determining the state of a rebar without electrical contact is taught.

A high-speed tensile testing machine conducts a tensile test on a test piece by applying a test force to the test piece. The high-speed tensile testing machine includes a detection unit configured to detect a test period indicating a time from when the test piece starts to deform under action of the test force to when the test piece breaks, and a determination unit configured to determine validity of a test result of the tensile test, on the basis of the test period and natural vibration of the high-speed tensile testing machine. Specifically, in the case where the test period is a predetermined multiple or more of a specific cycle indicating a cycle of the natural vibration of the high-speed tensile testing machine, the determination unit determines that the test result of the tensile test is valid.

A soft sensor includes an elastic sheet, which includes a first elastic layer and a second elastic layer facing each other, and a sensor unit formed by printing a predetermined conductive liquid metal between the first elastic layer and the second elastic layer. A hand-wearable device may include at least one soft sensor, wherein the hand-wearable device has a shape corresponding to at least a portion of a shape of a hand, and the soft sensor is located at a position corresponding to at least some joints of the hand.

The invention relates to a measurement device 1 comprising a rotatable magnetic object 4 which can oscillate with a resonant frequency if excited by an external magnetic torque. The measurement device 1 is adapted such that the resonant frequency depends on the temperature or on another physical or chemical quantity like pressure, in order to allow for a wireless temperature measurement or measurement of the other physical or chemical quantity via an external magnetic field providing the external magnetic torque. This measurement device can be relatively small, can be read-out over a relatively larger distance and allows for a very accurate measurement.

There is provided an elevator rope tension measurement system that can reduce measurement error when the tension of the rope of an elevator is quantitatively measured. An elevator rope tension measurement system includes a vibration waveform collection unit configured to collect a vibration waveform of a rope of an elevator; and a frequency calculation unit configured to select, based on a measurement resolution calculated from a collection time period and a collection cycle for collecting the vibration waveform by the vibration waveform collection unit, a method for calculating a frequency of the vibration waveform collected by the vibration waveform collection unit.

There is provided an elevator rope tension measurement system that can reduce measurement error when the tension of the rope of an elevator is quantitatively measured. An elevator rope tension measurement system includes a vibration waveform collection unit configured to collect a vibration waveform of a rope of an elevator; and a frequency calculation unit configured to select, based on a measurement resolution calculated from a collection time period and a collection cycle for collecting the vibration waveform by the vibration waveform collection unit, a method for calculating a frequency of the vibration waveform collected by the vibration waveform collection unit.

A system for estimating tension in a post-tensioned rod is provided. The system includes an impact device for transversely-impacting a post-tensioned rod, an accelerometer configured to generate data indicative of a vibrational response in the post-tensioned rod, and a receiver communicatively coupled to the accelerometer. The receiver includes a display, at least one input device, a communication module, a processor, and one or more memory devices coupled to the processor. Instructions stored on the one or more memory devices, when executed by the processor, cause the processor to receiver the data indicative of a vibrational response in the post-tensioned rod, process the received data to determine a difference between a first and a second modal frequency corresponding to the vibrational response, and store the difference between a first and second modal frequency corresponding to the vibrational response. The receiver is configured to transmit the stored difference between a first and second modal frequency.

A system for estimating tension in a post-tensioned rod is provided. The system includes an impact device for transversely-impacting a post-tensioned rod, an accelerometer configured to generate data indicative of a vibrational response in the post-tensioned rod, and a receiver communicatively coupled to the accelerometer. The receiver includes a display, at least one input device, a communication module, a processor, and one or more memory devices coupled to the processor. Instructions stored on the one or more memory devices, when executed by the processor, cause the processor to receiver the data indicative of a vibrational response in the post-tensioned rod, process the received data to determine a difference between a first and a second modal frequency corresponding to the vibrational response, and store the difference between a first and second modal frequency corresponding to the vibrational response. The receiver is configured to transmit the stored difference between a first and second modal frequency.