Multi-gas sensing system and method
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.
1. A multi-gas sensing system comprising:
a sensing circuit comprising one or more sensing elements, each of the one or more sensing elements comprising a sensing material configured to detect at least one gas analyte;
a management circuit configured to excite the one or more sensing elements with an alternating current at one or more predetermined frequencies, the management circuit configured to measure one or more electrical responses of the one or more sensing elements responsive to exciting the one or more sensing elements with the alternating current at the one or more predetermined frequencies, the management circuit configured to determine one or more characteristics of the sensing circuit based on the one or more electrical responses of the one or more sensing elements, wherein the one or more characteristics of the sensing circuit comprises a temperature of the one or more sensing elements; and
one or more processors configured to receive the one or more electrical responses of the one or more sensing elements and the one or more characteristics of the sensing circuit, wherein the one or more processors are configured to determine a concentration of the at least one gas analyte based on the one or more electrical responses of the one or more sensing elements and the one or more characteristics of the sensing circuit.
2. The multi-gas sensing system of claim 1 , wherein the management circuit is configured to manage a resistor-capacitor configuration of the one or more sensing elements, wherein the one or more processors are configured to determine the concentration of the at least one gas analyte based on the resistor-capacitor configuration of the one or more sensing elements.
3. The multi-gas sensing system of claim 1 , wherein the one or more characteristics of the sensing circuit includes a state of the sensing circuit based on a configuration of the one or more sensing elements or one or more ambient conditions proximate the sensing circuit.
4. The multi-gas sensing system of claim 1 , the sensing circuit further comprising a heating element, wherein the management circuit is configured to manage a temperature of the one or more sensing elements by controlling the heating element.
5. The multi-gas sensing system of claim 4 , wherein the one or more processors are configured to determine the concentration of the at least one gas analyte based on the one or more electrical responses of the one or more sensing elements operated at a constant temperature.
6. The multi-gas sensing system of claim 4 , wherein the management circuit is configured to synchronize the temperature of the one or more sensing elements with the excitation of the one or more sensing elements with the alternating current at the one or more predetermined frequencies.
7. The multi-gas sensing system of claim 1 , wherein the one or more processors are configured to receive information about one or more ambient conditions proximate the sensing circuit, wherein the one or more processors are configured to determine the concentration of the at least one gas analyte based on the one or more ambient conditions.
8. The multi-gas sensing system of claim 1 , wherein the sensing circuit is a resistor-capacitor sensing circuit.
9. The multi-gas sensing system of claim 1 , the sensing circuit further comprising a transducer and a heating element, wherein the one or more sensing elements, the sensing material, the transducer, and the heating element are disposed within a common housing.
10. The multi-gas sensing system of claim 1 , wherein the one or more processors are configured to determine the concentration of the at least one gas analyte based on electrical responses from two or more of the one or more sensing elements, wherein a first sensing element is configured to be operated at a first constant temperature, and a second sensing element is configured to be operated at a second constant temperature.
11. The multi-gas sensing system of claim 1 , wherein the one or more processors are configured to determine the concentration of the at least one gas analyte based on the electrical responses from two or more of the one or more sensing elements, wherein a first sensing element is configured to be operated at periodically variable temperatures, and a second sensing element is configured to be operated at different periodically variable temperatures.
12. The multi-gas sensing system of claim 1 , wherein the one or more processors are configured to determine the concentration of the at least one gas analyte based on the electrical responses from one of the one or more sensing elements, wherein the one sensing element is configured to be operated at periodically variable temperatures.
13. The multi-gas sensing system of claim 1 , wherein the one or more processors are configured to determine a baseline correction of the one or more electrical responses responsive to exciting the one or more sensing elements with the alternating current at the one or more predetermined frequencies based on the one or more characteristics of the sensing circuit.
14. The multi-gas sensing system of claim 1 , wherein the one or more processors are configured to dynamically change a selectivity of the sensing circuit.
15. The multi-gas sensing system of claim 1 , wherein the one or more processors are configured to dynamically change one or more of a selectivity or a sensitivity of the sensing circuit.
16. The multi-gas sensing system of claim 1 , wherein the one or more processors are configured to determine the concentration of the at least one gas analyte based on a multivariable transfer function.
17. The multi-gas sensing system of claim 16 , wherein the multivariable transfer function is based on one or more of the one or more electrical responses of the one or more sensing elements or the one or more characteristics of the sensing circuit.
18. The multi-gas sensing system of claim 1 , wherein the multi-gas sensing system is one or more of wearable, stationary, mobile, or airborne.
19. The multi-gas sensing system of claim 18 , wherein the wearable multi-gas sensing system is held within a transferable object.
20. The multi-gas sensing system of claim 1 , further comprising a gas-permeable membrane filter disposed over the one or more sensing elements.
21. The multi-gas sensing system of claim 20 , wherein the gas-permeable membrane filter includes a fluoropolymer.
22. The multi-gas sensing system of claim 1 , wherein the sensing material is an n-type semiconducting material, a p-type semiconducting material, or a combination of n-type and p-type semiconducting materials.
23. The multi-gas sensing system of claim 1 , wherein the management circuit is configured to excite the one or more sensing elements with the alternating current at the one or more predetermined frequencies at a high-frequency shoulder region of a relaxation peak or at a low-frequency shoulder region of the relaxation peak of a semiconducting material.
24. A multi-gas sensing system comprising:
a sensing circuit comprising one or more sensing elements, each of the one or more sensing elements comprising a sensing material configured to detect at least one gas analyte;
a management circuit configured to excite the one or more sensing elements with an alternating current at one or more predetermined frequencies, the management circuit configured to measure one or more electrical responses of the one or more sensing elements responsive to exciting the one or more sensing elements with the alternating current at the one or more predetermined frequencies, the management circuit configured to determine one or more characteristics of the sensing circuit based on the one or more electrical responses of the one or more sensing elements, wherein the one or more characteristics of the sensing circuit comprises a temperature of the one or more sensing elements; and
one or more processors configured to receive the one or more electrical responses of the one or more sensing elements and the one or more characteristics of the sensing circuit,
wherein the one or more processors are configured to determine a concentration of the at least one gas analyte based on the one or more electrical responses of the one or more sensing elements and the one or more characteristics of the sensing circuit,
wherein the one or more processors are configured to determine whether the concentration of the at least one gas analyte exceeds a predetermined threshold, and
wherein the one or more processors are configured to determine a responsive action of one or more of an asset or a subject responsive to determining that the concentration of the at least one gas analyte exceeds the predetermined threshold.