Sensor network system
A sensor network system that includes a sensor array having a plurality of sensor units that include a plurality of sensor elements, each sensor element configured to generate an electrical signal in response to a chemical environment in the vicinity of the sensor unit. The set of electrical signals generated by the sensor elements of the sensor unit represents a measured signature of the environment in the vicinity of the sensor unit. An analyzer is configured to extract the measured signatures of each sensor unit from sensor unit information signals and to detect a presence and concentration of one or more of the gases of interest based on the measured signatures.
1. A sensor network system, comprising:
a sensor array, the sensor array comprising a plurality of sensor units, each sensor unit comprising:
a plurality of sensor elements, at least some of the sensor elements of the plurality of sensor elements in the sensor unit disposed on a first substrate and comprising a printed component, wherein the plurality of sensor elements comprises:
a first group of sensor elements being sensitive to a first gas of interest and at least one sensor element of the first group is different in some functional respect from other sensor elements of the first group; and
a second group of sensor elements being sensitive to a second gas of interest, wherein at least one sensor element is part of the first and second groups,
wherein each sensor element in the plurality is configured to generate an electrical signal in response to a chemical environment in the vicinity of the sensor unit, the electrical signals generated by the sensor elements of the sensor unit representing a measured signature of the environment in the vicinity of the sensor unit;
aggregation circuitry disposed on a second substrate electrically coupled to the first substrate and configured to aggregate the electrical signals of the sensor elements into a sensor unit information signal; and
communication circuitry disposed on the second substrate and configured to wirelessly transmit the sensor unit information signal to an external receiver;
at least one base station communicatively coupled to the sensor array and configured to receive sensor unit information signals from each of the sensor units of the sensor array; and
an analyzer configured to extract the measured signature of each sensor unit from the sensor unit information signals and to detect presence and concentration of one or more gases of interest based on the measured signatures.
2. The system of claim 1 , wherein the analyzer is configured to determine confidence information for the presence and concentration of the gases of interest.
3. The system of claim 1 , wherein the system is further configured to detect one or more gases that interfere with detection of the gases of interest and the analyzer is configured to detect the presence and concentration of the gases of interest using information about the interfering gases.
4. The system of claim 1 , wherein the analyzer is configured to compare template signatures associated respectively with the gases of interest to the measured signatures and to detect presence and concentration of the gases of interest based on comparison of the template signatures with the measured signatures.
5. The system of claim 1 , wherein the analyzer is configured to develop a model of the one or more gases of interest by machine learning and is further configured to detect presence and concentration of the gases of interest based on the model.
6. The system of claim 1 , wherein the plurality of sensor elements comprises resistive sensors having conductive interdigitated electrodes bridged by a sensor material wherein at least one of the electrodes and the sensor material is printed.
7. The system of claim 6 , wherein the sensor material comprises carbon nanotubes with dopants or a metal oxide.
8. The system of claim 1 , wherein each sensor unit includes both printed and non-printed components, wherein the non-printed components include one or more of a battery, a passive electronic component, an integrated circuit, a wireless communications component, and a mechanical switch.
9. The system of claim 1 , wherein the sensor array is arranged such that each of the sensor units communicates with another sensor unit of the sensor array in a ring network and one sensor unit of the sensor array communicates with the base station or each of the sensor units communicates with the base station.
10. The system of claim 1 , wherein the sensor units are wirelessly coupled to the base station.
11. The system of claim 1 , wherein at least one of the base station and the sensor units include one or more environmental sensors.
12. The system of claim 1 , wherein the sensor array includes at least one of:
an energy harvesting component that supplies power to one or more sensor units;
an analog to digital converter (ADC) and a multiplexer configured to multiplex signals from each sensor unit to the ADC; and
redundant sensor units such that the sensor array remains operational if some sensor units of the sensor array fail.
13. The system of claim 1 , wherein the sensor units are configured to be placed at multiple locations and to detect gases at multiple locations independent of wind direction.
14. The system of claim 1 , wherein the analyzer is configured to provide information about one or more of a location of a gas leak, a direction of the gas leak, and a rate at which gas is being released from the gas leak.
15. The system of claim 14 , wherein the analyzer is configured to implement a parametric statistical method to provide the information.
16. The system of claim 14 , wherein the analyzer is configured to implement a non-parametric statistical method to provide the information.
17. The system of claim 1 , wherein at least one of the sensor elements does not comprise carbon nanotubes and at least one of the sensor elements comprises carbon nanotubes.
18. A method, comprising:
sensing using multiple sensor elements, at least some of the sensor elements of the multiple sensor elements disposed on a first substrate and comprising a printed component and at least some of the sensor elements of the multiple sensor elements being part of a first group of sensor elements sensitive to a first analyte of interest where at least one sensor element in the first group is different in some functional respect from at least one other sensor element in the first group, and some of the other sensor elements are part of a second group of sensor elements sensitive to a second analyte of interest where at least one sensor element is part of the first and second groups;
generating electrical output signals from the sensor elements in response to the sensing, the electrical output signals generated by the sensor elements of a sensor unit representing a measured signature of the environment in the vicinity of the sensor unit;
aggregating the electrical output signals using aggregation circuitry disposed on a second substrate electrically coupled to the first substrate into a sensor unit information signal that includes the measured signature;
transmitting the sensor unit information signal from the sensor unit;
receiving, in a base station, a plurality of sensor unit information signals from multiple sensor units, each sensor unit information signal including a respective measured signature;
extracting each of the measured signatures from the respective sensor unit information signals; and
determining a presence and concentration of the first and second analytes based on analysis of the extracted measured signatures.
19. The method of claim 18 , wherein determining the presence and concentration of the first and second analytes comprises:
comparing the extracted measured signatures to template signatures and determining the presence and concentration based on the comparing; and
updating the template signatures and/or learning new signatures based on the measured signatures.
20. The method of claim 18 , wherein determining the presence and concentration of the first and second analytes comprises determining the presence and concentration based on a model developed by machine learning.
21. The method of claim 18 , further comprising providing information about one or more of a location of a gas leak and a rate at which gas is being released from the gas leak.