Abstract: A sensor system is described with improved measurement accuracy that is achieved by reducing noise, baseline drift, or both based on processing a group of sensor element response signals. The response signals may be received in response to providing stimuli to the sensor element using different excitation frequencies over time. For example, the sensor circuitry may provide excitation signals to the sensing element with multiple excitation frequencies over time. The sensor system may include storage and processing circuitry to receive the response signals and to generate the correction values based on analyzing the received response signals. The sensor system may then provide adjusted response signals by reducing the noise, baseline drift, or both based on the correction values.

Abstract: An electrochemical gas sensor for multi-gas analysis of a fluid sample includes an electrochemical gas sensing element and a data collection component. The data collection component is configured to cycle the electrochemical gas sensing element between first excitation and signal detection values and second excitation and signal detection values at a predetermined time constant, and to measure responses of the electrochemical gas sensor to the fluid sample at the first excitation and signal detection values and the second excitation and signal detection values wherein the responses of the electrochemical gas sensor to the fluid sample at the first excitation and signal detection values and the second excitation and signal detection values are indicative of identities, respective concentrations, or a combination thereof, of at least two analyte gases of the fluid sample.

Abstract: A system and a method for multi-gas sensing using dielectric excitation of a single sensing material at multiple operating temperatures. By measuring dielectric excitation responses of the gas sensing material, enhanced multi-gas differentiation and differentiation can be achieved using fewer operating temperatures than would be used by the same MOS gas sensing material configured to perform multi-gas differentiation based on resistance responses alone. The disclosed gas sensors and gas sensing techniques enable improved response linearity, improved dynamic range, and reduced computational resource consumption for multi-gas quantitation relative to traditional resistance-based gas sensing methods.

Abstract: A system and a method for gas sensing while correcting for a poison level of a gas sensor. The gas sensor provides first dielectric excitation of the gas sensing material at a first set of frequencies, measures responses of the gas sensing material to the first dielectric excitation while the gas sensing material is in contact with the fluid sample, provides second dielectric excitation of the gas sensing material at a second set of frequencies, measures responses of the gas sensing material to the second dielectric excitation while the gas sensing material is in contact with the fluid sample, and determines, based on the responses of the gas sensing material to the first and second dielectric excitation, identities, respective concentrations, or a combination thereof, of at least one analyte gas in a fluid sample, and a sensor poison level of the gas sensing material.

Abstract: A system and a method for gas sensing while correcting for an interferent condition around a gas sensor. The gas sensor provides dielectric excitation of a gas sensing element and an interferent-compensating sensing element arranged as a single electrical circuit at a set of frequencies, measures impedance responses of the gas sensing element and the interferent-compensating sensing element to the dielectric excitation at the set of frequencies, determines, based on the impedance responses of the gas sensing element and the interferent-compensating sensing element to the dielectric excitation the identities, the respective concentrations, or a combination thereof, of at least one analyte gas of the monitored environment, corrected for one or more sensed interferent conditions of the ambient environment.

Abstract: Gas sensors are disclosed having an on-board, low-power data processor that uses multivariable gas classification and/or gas quantitation models to perform on-board data processing to resolve two or more gases in a fluid sample. To reduce computational complexity, the gas sensor utilizes low-power-consumption multivariable data analysis algorithms, inputs from available on-board sensors of ambient conditions, inputs representing contextual data, and/or excitation responses of a gas sensing material to select suitable gas classification and/or gas quantitation models. The data processor can then utilize these gas classification and quantitation models, in combination with measured dielectric responses of a gas sensing material of the gas sensor, to determine classifications and/or concentrations of two or more gases in a fluid sample, while consuming substantially less power than would be consumed if a global comprehensive model were used instead.

Abstract: A system and a method for multi-gas sensing using dielectric excitation of a single sensing material operated at a single operating temperature. Contrary to conventional gas sensor designs, embodiments of the gas sensors disclosed herein implement a metal oxide semiconductor sensing material maintained at a constant temperature, wherein dielectric excitation responses of the sensing material are measured at this constant temperature while the sensing material is exposed to a fluid sample. The disclosed gas sensors and gas sensing methods unexpectedly provide desirable characteristics, such as enhanced multi-gas differentiation, while operating at the constant operating temperature.

Abstract: A multi-gas sensing system includes a sensing circuit comprising one or more sensing elements. Each sensing element includes a sensing material configured to detect at least one gas analyte. A management circuit is configured to excite the sensing elements with an alternating current at at least one predetermined frequency. The management circuit measures one or more electrical responses of the sensing elements responsive to exciting the sensing elements with the alternating current. The management circuit determines one or more characteristics of the sensing circuit. One or more processors receive the electrical responses of the sensing elements and the characteristics of the sensing circuit. The one or more processors determine a concentration of the at least one gas analyte based on the electrical responses of the sensing elements and the characteristics of the sensing circuit.

Abstract: A sensor system includes an unmanned vehicle system is provided that includes a housing, and an environmental sensor system coupled to the housing, the environmental sensor system configured to detect one or more environmental conditions of an environment in operational contact with the unmanned vehicle system. The environmental sensor includes a sensing element that includes a sensing material to detect and quantify at least one analyte gas by measuring impedance of the sensing element at one or more frequencies of the different frequencies during exposure of the sensing material to the at least one analyte gas.

Abstract: A sensor system includes a sensing element having a section of a layer assembly deposited onto a substrate. The layer assembly includes plural layers of different materials. The section of the layer assembly is configured to be etched to form plural individual pillars of the plural layers of the different materials. The individual pillars are configured to be in contact with a fluid to sense one or more analyte fluid components within the fluid. The sensing element is configured to generate a sensor signal responsive to the individual pillars being in contact with the fluid. The sensor system includes one or more processors configured to receive the sensor signal from the sensing element. The one or more processors may identify the one or more analyte fluid components within the fluid and an amount of each of the analyte fluid components within the fluid based on the sensor signal.

Abstract: A sensor system includes a multi-frequency sensor assembly including a single sensor body housing with a sensing region circuit and a sensor reader disposed in the sensor body. The sensor body is configured to be in operational contact with a fluid. The sensing region circuit is configured to generate different electric fields having different frequencies in the fluid. The sensor reader includes one or more processors configured to examine one or more impedance responses of the sensing region circuit at different frequencies and to determine one or more properties of the fluid based on the one or more impedance responses that are examined.

Abstract: A monolithic gas-sensing chip assembly for sensing a gas analyte includes a sensing material to detect the gas analyte, a sensing system including a resistor-capacitor electrical circuit, and a heating element. A sensing circuit measures an electrical response of the sensing system to an alternating electrical current applied to the sensing system at (a) one or more different frequencies, or (b) one or more different resistor-capacitor configurations of the system. One or more processors control a low detection range of the system to the gas, a high detection range of the system to the gas, a linearity of a response of the system to the gas, a dynamic range of measurements of the gas by the system, a rejection of interfering gas analytes by the system, a correction for aging or poisoning of the system, or a rejection of ambient interferences that may affect the electrical response of the system.

Abstract: A gas sensing assembly includes a sensing material to be placed in contact with a fluid sample, electrodes coupled with the sensing material that apply an electric field to the sensing material across the electrodes, a heating element that controls a temperature of the sensing material while the sensing material is in contact with the fluid sample, and sensing circuitry to control application of the electric field to the sensing material via the electrodes at an alternating current frequency range in the presence of an uncontrolled ambient temperature and at an elevated alternating current frequency range. The sensing circuitry measures one or more electrical responses of the sensing material responsive to applying the electric field at the alternating current frequency range and at the elevated alternating current frequency range. The sensing circuitry detects presence of a gas in the fluid sample based on the one or more electrical responses.

Abstract: A sensor system includes a sensing element that includes a sensing material and electrodes configured to apply a first electrical stimuli to the sensing material at an electrical excitation frequency, a modifier assembly including one or more circuits configured to change an electrical impedance of the sensing element, and one or more processors configured to control the modifier assembly. Responsive to exposure of gas to the sensing element, the one or more processors change a linearity of a first electrical signal received from the sensing element by changing the electrical impedance of the sensing element and applying a second electrical stimuli to the sensing material at the electrical excitation frequency.

Abstract: A sensor system includes an electrical circuit having plural leads coupled with one or more sensing regions. The sensing regions include gaps having sensing materials that detect an analyte of interest. The gaps close responsive to the sensing material corresponding to the gaps detecting the analyte of interest. One or more processors communicatively coupled with the electrical circuit receive electrical signals from the electrical circuit indicative of the gaps closing responsive to the sensing material of the corresponding gaps detecting the analyte of interest. The electrical circuit is in a closed position in the presence of the analyte of interest. The sensor system is configured to consume an increased amount of power when the electrical circuit is in the closed position relative to the electrical circuit in an open position responsive to the one or more of the gaps closing. A responsive action is determined based on the electrical signals.

Abstract: An inspection apparatus includes a communication unit including a first transmitter and a second transmitter. The communication unit is coupled to an on-board computing device including at least one processor coupled to a memory device. The processor is configured to obtain a position of the inspection apparatus, unprocessed image data, and fluid concentration data for at least one fluid. The processor geotags the data with the position of the inspection apparatus and transmits the data to a remote processing device. The geotagged image data is transferred using the first transmitter and the geotagged fluid concentration data is transmitted using the second transmitter.

Abstract: A resonant sensor probe assembly includes a substrate formed from one or more dielectric materials and free-standing electrodes coupled with the substrate. The free-standing electrodes are configured to be placed into the fluid and to generate an electric field between the free-standing electrodes. A controller measures an impedance response of the sensor to the fluid between the electrodes to determine an aging effect of the sensor.

Abstract: A system for analysis of at least one analyte gas present in an insulating fluid of an electrical transformer includes a gas sensor in operational contact with at least one analyte gas from an insulating fluid to provide multiple responses from the sensor. One or more processors are configured to receive the multiple responses during exposure of the sensor to the analyte gas from the insulating fluid representative of a concentration of the analyte gas present in the insulating fluid. The processors are configured to select one or more responses of the multiple responses that provide rejection of interfering gases, resolution between gases, improved low detection range of the analyte gas, improved high detection range of the analyte gas, improved response linearity of the analyte gas, improved dynamic range of measurements of the analyte gas, or one or more combinations thereof compared to non-selected responses from the sensor.

Abstract: A monolithic gas-sensing chip assembly for sensing a gas analyte includes a sensing material to detect the gas analyte, a sensing system including a resistor-capacitor electrical circuit, and a heating element. A sensing circuit measures an electrical response of the sensing system to an alternating electrical current applied to the sensing system at (a) one or more different frequencies, or (b) one or more different resistor-capacitor configurations of the system. One or more processors control a low detection range of the system to the gas, a high detection range of the system to the gas, a linearity of a response of the system to the gas, a dynamic range of measurements of the gas by the system, a rejection of interfering gas analytes by the system, a correction for aging or poisoning of the system, or a rejection of ambient interferences that may affect the electrical response of the system.

Abstract: A resonant sensor probe assembly includes a substrate formed from one or more dielectric materials and free-standing electrodes coupled with the substrate. The free-standing electrodes are configured to be placed into the fluid and to generate an electric field between the free-standing electrodes. A controller measures an impedance response of the sensor to the fluid between the electrodes to determine an aging effect of the sensor.