A moisture detection element includes: an insulating substrate of an insulating material; an application part which is formed on the insulating substrate and to which a voltage is applied; an output part which is formed on the insulating substrate and configured to output a voltage signal corresponding in response to a current flowing through an electric path via water molecules adhering to a surface of the insulating substrate under the voltage applied to the application part; and a conductive film which is electrically insulated from the application part and the output part and is provided on the insulating substrate. An insulating film of an insulating material is provided on the application part, the output part, and the conductive film.

A gas sensor that selectively detects and/or measures acetylene and/or ethylene includes a substrate; at least one electrode pair; at least one gas-sensitive layer consisting of at least one metal oxide from the group ReFeO.sub.3 and in contact with the at least one electrode pair; a heating element; and at least one control device, wherein the heating element is adapted to be heated alternately to at least two different temperatures of 150° C.-250° C., 200° C.-300° C. and 250° C.350° C., respectively, by the control device.

A gas sensor system includes a gas sensing element that includes a gas sensing material and electrodes configured to apply electrical stimuli to the gas sensing material and one or more processors configured to control the gas sensing element. The one or more processors are configured to direct the electrodes to apply the electrical stimuli at two or more different electrical excitation frequencies to the gas sensing material. A first electrical excitation frequency of the two or more different electrical excitation frequencies is configured to provide a quantitative gas response of the gas sensing material, the quantitative gas response including a response drift. A second electrical excitation frequency of the two or more different electrical excitation frequencies is configured to provide a baseline response of the gas sensing material based at least in part on the response drift.

Ultrasensitive, decoupled thermodynamic sensing platforms for the detection of chemical compounds in the vapor phase at trace levels are disclosed, wherein the sensors have a heating resistor decoupled from a sensing resistor. Embodiments of the decoupled sensor comprise a metallic microheater resistor on one side of substrate, and a sensor resistor coupled to a catalyst on the other side of the substrate. A sensor array may be provided including a plurality of sensors each having a different catalyst that, when exposed to an analyte, each experience an endothermic reaction, an exothermic reaction, or no reaction. A comparison of the reaction results to data comprising previously obtained reaction results may be used to determine the presence and the identity of the analyte. Advantageously, the decoupled sensors utilize less power and provide greater sensitivity than other known systems, and may be used to detect and identify a single molecule of an analyte.

Molybdenum oxide is doped with vanadium, nobidium, tantalum or titanium to form a stable M.sub.5O.sub.14 theta phase crystal structure as a vapor sensitive material for detecting vapors of volatile organic compounds. That material is used between electrodes connected to a measuring device to measure a change in an electrical quality in the presence of a vapor of a volatile organic compound. Concentration of the vapor is measured to low part per million ranges.

Minimal-cost, high-accuracy, and portable devices used to detect the presence of insects at all stages of life, including in the egg stage, in stored products by sensing gas phase markers such as volatile pheromones, semiochemicals, and kairomones. The methods, devices, and systems disclosed herein utilize a sensor array configured to simultaneously measure a plurality of target markers and filter background gases while remaining compact, highly accurate, and easy to operate.

In an embodiment a sensor device include a first sensor including a heating element configured to heat up the first sensor in a controllable manner and a second sensor thermally coupled to the heating element of the first sensor such that the heating element is further configured to heat up the second sensor in a controllable manner.

According to one embodiment, a hydrogen sensor is disclosed. The hydrogen sensor includes a capacitor, a gas detector, a heater, and a determiner. The capacitor includes a deformable member that deforms by absorbing or adsorbing hydrogen and varies a capacitance value corresponding to a deformation of the deformable member. The gas detector detects gas based on a capacitance value of the capacitor. The heater heats the deformable member. The determiner determines whether gas detected by the gas detector contains a substance other than hydrogen or not, wherein the gas detector detects the gas during a heating period during which the heater heats the deformable member.

In an embodiment an electro-thermal device includes a heater, a readout circuit, a digital controller having a first input coupled to a first output of the readout circuit and a digital sigma-delta modulator having a first input coupled to an output of the digital controller and an output coupled to the heater.

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. A control unit includes one or more processors coupled with the environmental sensor and configured to receive a detector signal from the detector circuit of the environmental sensor indicative of the one or more environmental conditions, and control the movement of the unmanned vehicle system based on an operation signal of a remote device, instructions received at a vehicle controller, the detector signal, or in response to detected route conditions.