Abstract: The disclosure describes techniques for detecting a crack or defect in a material.

Abstract: A technique may include applying a first electrical signal to a first pair of drive electrodes, and, while applying the first electrical signal to the first pair of drive electrodes, determining a first measured voltage using a first measurement electrode. The technique further may include applying a second electrical signal to a second pair of drive electrodes, and, while applying the second electrical signal to the second pair of drive electrodes, determining a second measured voltage using a second, different measurement electrode. The first pair of drive electrodes, the second pair of drive electrodes, the first measurement electrode, and the second, different measurement electrode may from a set of N electrodes electrically coupled to the material. The technique also may include determining whether the material includes a crack or other defect based on a comparison between the first measured voltage and the second measured voltage.

Abstract: The disclosure describes techniques for detecting a crack or defect in a material. The technique may include applying an electrical signal to a first electrode pair electrically coupled to the material. The technique also may include, while applying the electrical signal to the first electrode pair, determining a measured voltage between a second, different electrode pair. At least one electrode of the second, different electrode pair is electrically coupled to the material. The technique may further include determining a corrected measured voltage by suppressing a thermally induced voltage from the measured voltage and determining whether the material includes a crack or other defect based on the corrected measured voltage.

Abstract: An armor piece may include a tested material. The armor piece also may include a plurality of electrical contacts distributed about and electrically connected to the tested material. The armor piece further may include a non-volatile memory (NVM) device. The NVM device may be hardened against exposure to x-ray radiation. The NVM device may be configured to store control voltages associated with respective electrical contacts of the plurality of electrical contacts.

Abstract: A data communication apparatus, system, and method are described. The data communication system comprises a transceiver disposed on an entrance port to an enclosure, such as an underground enclosure. The transceiver includes a housing, the housing mountable to the entrance port, wherein the transceiver is configured to communicate with a network outside of the underground enclosure. The data communication system also includes a monitoring device disposed in the underground enclosure that provides data related to a real-time condition within the underground enclosure. The data communication system also includes a sensor analytics unit to process the data from the monitoring device/sensor and generate a processed data signal and to communicate the processed data signal to the transceiver.

Abstract: A measurement system may include control electronics; an electrical signal source; a plurality of measurement system electrical contacts; at least one feature for repeatably electrically connecting the plurality of measurement system electrical contacts to selected locations of a tested material. The control electronics may be configured to cause the electrical signal source to output an electrical signal; determine a measured voltage in response to the electrical signal using a measurement electrical contact from the plurality of measurement system electrical contacts. The measurement electrical contact is electrically coupled to the tested material. The control electronics also may be configured to determine whether the tested material includes a crack or other defect based on the measured voltage.

Abstract: Systems and methods for detecting a crack or defect in a material are described. An example method may include determining, by a computing device, for each respective adjacent pair of electrodes of a plurality of electrodes electrically coupled to the material, a respective electrode pair voltage. The method also may include determining, by the computing device, for each respective adjacent pair of electrodes, a respective temperature-corrected electrode pair value based on the respective electrode pair voltage and at least one of a respective control voltage associated with the respective adjacent pair of electrodes or a temperature correction factor. The method may further include determining, by the computing device, whether the material includes a crack or defect based on the plurality of respective temperature-corrected electrode pair values.

Abstract: A measurement system may include an electrical signal source; a plurality of electrical contacts electrically coupled to a tested material; a respective resistor associated with each electrical contact; a common node to which the respective resistors are electrically connected; and a control module. The control module may cause the electrical signal source to be electrically connected to a selected electrical contact as an input electrical contact. The remaining electrical contacts are electrically connected to a return node of the electrical signal source as extraction electrical contacts. The control module also may cause the electrical signal source to output an electrical signal to an input electrical contact; cause a respective electrical signal parameter to be determined at the respective resistor associated with each respective extraction electrical contact; and determine whether the tested material includes a crack or other defect based on the respective electrical signal parameters.

Abstract: The disclosure describes techniques for detecting a crack or defect in a material. The technique may include applying an electrical signal to a first electrode pair electrically coupled to the material. The technique also may include, while applying the electrical signal to the first electrode pair, determining a measured voltage between a second, different electrode pair. At least one electrode of the second, different electrode pair is electrically coupled to the material. The technique may further include determining a corrected measured voltage by suppressing a thermally induced voltage from the measured voltage and determining whether the material includes a crack or other defect based on the corrected measured voltage.

Abstract: A method may include coupling a first electrical connector of an article to a second electrical connector of a measurement device. The article may include a tested material, the first electrical connector, and a plurality of electrical contacts electrically connected to the first electrical connector. The measurement device may include a power source and a user interface. The method also may include causing, by a controller, an electrical signal to be applied to a pair of drive electrical contacts from the plurality of electrical contacts. The method further may include receiving, by the controller, from an analog-to-digital converter, a measured voltage measured using a measurement electrical contact from the plurality of electrical contacts. The method also may include determining, by the controller, whether the tested material includes a crack or other defect based on the measured voltage.

Abstract: A measurement system may include a set of drive electrical contacts including a force electrical contact and a return electrical contact electrically coupled to a tested material, a measurement electrical contact electrically coupled to the tested material, a return node, a voltage source, and a control module. A circuit path between the voltage source and the return node may include a fixed resistor and the tested material. The control module may be configured to cause the voltage source to apply a voltage signal to the force electrical contact, cause a voltage drop across the fixed resistor to be measured, cause a measured voltage to be measured using the measurement electrical contact, determine a measured equivalent impedance of the tested material associated with the measurement electrical contact based on the voltage drop across the fixed resistor and the measured voltage, and determine whether the tested material includes a crack or other defect based on the measured equivalent impedance.

Abstract: The disclosure describes techniques for detecting a crack or defect in a material.

Abstract: The disclosure describes techniques for detecting a crack or defect in a material. The technique may include applying an electrical signal to a first electrode pair electrically coupled to the material. The technique also may include, while applying the electrical signal to the first electrode pair, determining a measured voltage between a second, different electrode pair. At least one electrode of the second, different electrode pair is electrically coupled to the material. The technique may further include determining a corrected measured voltage by suppressing a thermally induced voltage from the measured voltage and determining whether the material includes a crack or other defect based on the corrected measured voltage.

Abstract: A technique may include applying a first electrical signal to a first pair of drive electrodes, and, while applying the first electrical signal to the first pair of drive electrodes, determining a first measured voltage using a first measurement electrode. The technique further may include applying a second electrical signal to a second pair of drive electrodes, and, while applying the second electrical signal to the second pair of drive electrodes, determining a second measured voltage using a second, different measurement electrode. The first pair of drive electrodes, the second pair of drive electrodes, the first measurement electrode, and the second, different measurement electrode may from a set of N electrodes electrically coupled to the material. The technique also may include determining whether the material includes a crack or other defect based on a comparison between the first measured voltage and the second measured voltage.

Abstract: The disclosure describes techniques for detecting a crack or defect in a material. A computing device may determine whether a tested material includes a crack or other defect based on a temperature-scaled control data set and a measurement data set.

Abstract: A technique may include applying a first electrical signal to a first pair of drive electrodes, and, while applying the first electrical signal to the first pair of drive electrodes, determining a first measured voltage using a first measurement electrode. The technique further may include applying a second electrical signal to a second pair of drive electrodes, and, while applying the second electrical signal to the second pair of drive electrodes, determining a second measured voltage using a second, different measurement electrode. The first pair of drive electrodes, the second pair of drive electrodes, the first measurement electrode, and the second, different measurement electrode may from a set of N electrodes electrically coupled to the material. The technique also may include determining whether the material includes a crack or other defect based on a comparison between the first measured voltage and the second measured voltage.

Abstract: A data communication apparatus, system, and method are described. The data communication system comprises a transceiver disposed on an entrance port to an enclosure, such as an underground enclosure. The transceiver includes a housing, the housing mountable to the entrance port, wherein the transceiver is configured to communicate with a network outside of the underground enclosure. The data communication system also includes a monitoring device disposed in the underground enclosure that provides data related to a real-time condition within the underground enclosure. The data communication system also includes a sensor analytics unit to process the data from the monitoring device/sensor and generate a processed data signal and to communicate the processed data signal to the transceiver.

Abstract: An armor piece may include a tested material. The armor piece also may include a plurality of electrical contacts distributed about and electrically connected to the tested material. The armor piece further may include a non-volatile memory (NVM) device. The NVM device may be hardened against exposure to x-ray radiation. The NVM device may be configured to store control voltages associated with respective electrical contacts of the plurality of electrical contacts.

Abstract: A data communication apparatus, system, and method are described. The data communication system comprises a transceiver disposed on an entrance port to an enclosure, such as an underground enclosure. The transceiver includes a housing, the housing mountable to the entrance port, wherein the transceiver is configured to communicate with a network outside of the underground enclosure. The data communication system also includes a monitoring device disposed in the underground enclosure that provides data related to a real-time condition within the underground enclosure. The data communication system also includes a sensor analytics unit to process the data from the monitoring device/sensor and generate a processed data signal and to communicate the processed data signal to the transceiver.

Abstract: An armor piece may include a tested material. The armor piece also may include a plurality of electrical contacts distributed about and electrically connected to the tested material. The armor piece further may include a non-volatile memory (NVM) device. The NVM device may be hardened against exposure to x-ray radiation. The NVM device may be configured to store control voltages associated with respective electrical contacts of the plurality of electrical contacts.