In certain embodiments, an apparatus includes a sensing element having a capacitance to a first reference voltage. The capacitance is variable as a function of a proximity of an object to the sensing element. The apparatus further includes a sample capacitor connected to the sensing element and control circuitry connected to the sample capacitor. The control circuitry is configured to supply a charge to the sample capacitor and the sensing element and discharge the sensing element. The control circuitry is further configured to provide, in response to the discharge of the sensing element, a signal indicative of the capacitance to the first reference voltage of the sensing element. The control circuitry is further configured to process the signal to detect a change in the capacitance to the first reference voltage as indicative of the proximity of the object to the sensing element.

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 differential mode converter that includes an input mode converter configured to convert an input voltage in a single-ended mode into a first differential voltage and a second differential voltage to be output, the first differential voltage and the second differential voltage being symmetric with respect to a reference voltage and having a form of a square wave; and a chopper configured to receive the first differential voltage and the second differential voltage and determine a first chopping voltage and a second chopping voltage based on the first differential voltage and the second differential voltage to output the first chopping voltage and the second chopping voltage, the first chopping voltage and the second chopping voltage being symmetric with respect to the reference voltage and having a form of a DC voltage.

A differential mode converter that includes an input mode converter configured to convert an input voltage in a single-ended mode into a first differential voltage and a second differential voltage to be output, the first differential voltage and the second differential voltage being symmetric with respect to a reference voltage and having a form of a square wave; and a chopper configured to receive the first differential voltage and the second differential voltage and determine a first chopping voltage and a second chopping voltage based on the first differential voltage and the second differential voltage to output the first chopping voltage and the second chopping voltage, the first chopping voltage and the second chopping voltage being symmetric with respect to the reference voltage and having a form of a DC voltage.

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.

Methods and apparatuses for detecting tension on a tendon and/or mechanical deformation (e.g., breakage) of one or more steering tendon of a steerable and flexible articulating device. Theses apparatuses may have one or more tendons that are each electrically conductive and configured to steer the apparatus when tension is applied to the proximal end of the tendon. Tension and/or breakage (or other deformation) of one or more of these tendons may be detected by monitoring the electrical resistance of the tendons.

Disclosed herein is a system for non-contact measurement of an optoelectronic property. The system includes a sensing element configured to amplify an electromagnetic wave having a specific frequency, a thin film disposed on the sensing element such that an optoelectronic property of the thin film is measured, and an optoelectronic property measuring server configured to extract a physical property of the thin film based on the optoelectronic property of the thin film obtained when the electromagnetic wave amplified by the sensing element passes through the thin film.

Various aspects of the disclosure relate to evaluating the electromagnetic impedance characteristics of a material under test (MUT) over a range of frequencies. In particular aspects, a system includes: an electrically non-conducting container sized to hold the MUT, the electrically non-conducting container having a first opening at a first end thereof and a second opening at a second, opposite end thereof; a transmitting electrode assembly at the first end of the electrically non-conducting container, the transmitting electrode assembly having a transmitting electrode with a transmitting surface; and a receiving electrode assembly at the second end of the electrically non-conducting container, the receiving electrode assembly having a receiving electrode with a receiving surface, wherein the receiving electrode is approximately parallel with the transmitting electrode, and wherein the transmitting surface of the transmitting electrode is larger than the receiving surface of the receiving electrode.

Various aspects of the disclosure relate to evaluating the electromagnetic impedance characteristics of a material under test (MUT) over a range of frequencies. In particular aspects, a system includes: an electrically non-conducting container sized to hold the MUT, the electrically non-conducting container having a first opening at a first end thereof and a second opening at a second, opposite end thereof; a transmitting electrode assembly at the first end of the electrically non-conducting container, the transmitting electrode assembly having a transmitting electrode with a transmitting surface; and a receiving electrode assembly at the second end of the electrically non-conducting container, the receiving electrode assembly having a receiving electrode with a receiving surface, wherein the receiving electrode is approximately parallel with the transmitting electrode, and wherein the transmitting surface of the transmitting electrode is larger than the receiving surface of the receiving electrode.

A method of measuring electrical characteristics of a transducer in a wind turbine generator control system is described. The method comprises measuring one or more electrical characteristics of a transducer of the control system, and comparing the measured electrical characteristics to one or more reference electrical characteristics, the reference electrical characteristics being one of (a) previously measured electrical characteristics of that transducer, (b) reference electrical characteristics stored in a database, and (c) previously measured electrical characteristics of an identical or similar transducer in another wind turbine generator.