Integrated, miniaturized, wireless sensing electronics platform for high-resolution gas sensing

Abstract

The subject of the present invention is "Integrated, miniaturized, wireless sensing electronic platform for high-resolution gas sensing". An electronic sensing system located on a printed circuit board is provided. The electronic sensing system includes: a target gas sensor, the target gas sensor is configured to detect the resistance of the target gas sensor; a reference sensor, the reference sensor is configured to detect the resistance of the reference sensor; a resistance comparator, the resistance comparator includes a digital potentiometer, the resistance comparator is electrically connected to the target gas sensor and the reference sensor, wherein the digital potentiometer is configured to be adjusted to determine a first resistance in response to the resistance of the target gas sensor and to determine a second resistance in response to the resistance of the reference sensor; and a system on a chip in electronic communication with the resistance comparator, the system on a chip being configured to determine the target gas concentration in response to the first resistance and the second resistance.

Description

Background Art

[0001] The subject matter disclosed herein relates generally to gas sensing, and more particularly to apparatus and methods for sensing gas.

[0002] Detecting a target gas (eg, ethylene) in the presence of contaminants such as, for example, carbon dioxide and carbon monoxide is often difficult. Summary of the invention

[0003] According to one embodiment, an electronic sensing system located on a printed circuit board is provided. The electronic sensing system includes: a target gas sensor, the target gas sensor configured to detect the resistance of the target gas sensor; a reference sensor, the reference sensor configured to detect the resistance of the reference sensor; a resistance comparator, the resistance comparator including a digital potentiometer, the resistance comparator is electrically connected to the target gas sensor and the reference sensor, wherein the digital potentiometer is configured to be adjusted to determine a first resistance in response to the resistance of the target gas sensor and to determine a second resistance in response to the resistance of the reference sensor; and a system on a chip in electronic communication with the resistance comparator, the system on a chip configured to determine a target gas concentration in response to the first resistance and the second resistance.

[0004] In addition to one or more of the features described above, or as an alternative, further embodiments may include: a multiplexer that electrically connects the resistance comparator to the target gas sensor and the reference sensor, wherein the multiplexer includes: a first port electrically connected to the target gas sensor, a second port electrically connected to the reference sensor, and an output port electrically connected to the resistance comparator.

[0005] In addition to or as an alternative to one or more of the features described above, further embodiments may include that the system on chip further includes a general purpose input output in electronic communication with the multiplexer.

[0006] In addition to or as an alternative to one or more of the features described above, further embodiments may include a humidity sensor configured to detect humidity on-board of the electronic sensing system.

[0007] In addition to or as an alternative to one or more of the features described above, further embodiments may include a temperature sensor configured to detect an on-board temperature of the electronic sensing system.

[0008] In addition to or as an alternative to one or more of the features described above, further embodiments may include that the system on chip further includes an I2C in electronic communication with the humidity sensor.

[0009] In addition to or as an alternative to one or more of the features described above, further embodiments may include that the system on chip further includes an I2C in electronic communication with the temperature sensor.

[0010] In addition to or as an alternative to one or more of the features described above, further embodiments may include that the system on chip is configured to adjust the first resistor and the second resistor to compensate for on-board humidity.

[0011] In addition to or as an alternative to one or more of the features described above, further embodiments may include that the system on chip is configured to adjust the first resistance and the second resistance to compensate for on-board temperature.

[0012] In addition to or as an alternative to one or more of the features described above, further embodiments may include that the system on chip further includes an I2C in electronic communication with the resistance comparator.

[0013] In addition to or as an alternative to one or more of the features described above, further embodiments may include: a low pass filter; an amplifier; and an analog to digital converter, wherein the I2C electronically communicates with the resistor comparator through the low pass filter, the amplifier, and the analog to digital converter.

[0014] In addition to or as an alternative to one or more of the features described above, further embodiments may include: the system on chip further comprising: a communication device configured to broadcast a wireless signal.

[0015] In addition to or as an alternative to one or more of the features described above, further embodiments may include that the wireless signal is Bluetooth.

[0016] In addition to or as an alternative to one or more of the features described above, further embodiments may include that the communication device is configured to transmit the target gas concentration to an external device via a wireless signal.

[0017] In addition to or as an alternative to one or more of the features described above, further embodiments may include: a thermistor configured to measure an off-board temperature, wherein the system-on-chip is configured to adjust the on-board temperature in response to the off-board temperature.

[0018] In addition to, or as an alternative to, one or more of the features described above, further embodiments may include that the target gas is ethylene.

[0019] According to another embodiment, a method for detecting a target gas is provided. The method includes: detecting a resistance of a target gas sensor; detecting a resistance of a digital potentiometer; adjusting the resistance of the digital potentiometer to a first resistance so that the first resistance of the digital potentiometer matches the resistance of the target gas sensor; detecting a resistance of a reference sensor; adjusting the resistance of the digital potentiometer to a second resistance so that the second resistance of the digital potentiometer matches the resistance of the target gas sensor; and determining a target gas concentration in response to the first resistance and the second resistance.

[0020] In addition to one or more of the features described above, or as an alternative, another embodiment may include: before the determination, the method further includes: using a humidity sensor to detect the humidity on the board; and adjusting the first resistor and the second resistor in response to the humidity on the board to compensate for the humidity on the board.

[0021] In addition to one or more of the features described above, or as an alternative, another embodiment may include: before the determination, the method further includes: using a temperature sensor to detect the on-board temperature; and adjusting the first resistor and the second resistor in response to the on-board temperature to compensate for the on-board temperature.

[0022] In addition to one or more of the features described above, or as an alternative, another embodiment may include: before the determination, the method further includes: using a humidity sensor to detect the humidity on the board; using a temperature sensor to detect the temperature on the board; and adjusting the first resistor and the second resistor in response to the humidity on the board and the temperature on the board to compensate for the humidity on the board and the temperature on the board.

[0023] The foregoing features and elements may be combined in various combinations without exclusivity, unless otherwise expressly indicated. These features and elements and their operation will become more apparent in view of the following description and accompanying drawings. However, it should be understood that the following description and accompanying drawings are intended to be illustrative and explanatory in nature and are non-restrictive. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The following description should not be considered limiting in any way. Referring to the drawings, similar elements are similarly numbered.

[0025] Figure 1 illustrates a general schematic system diagram of an electronic sensing system according to an embodiment of the present disclosure;

[0026] Figure 2 illustrates a general schematic system diagram of an electronic sensing system according to an embodiment of the present disclosure; and

[0027] Figure 3 It is a diagram illustrating the use of an embodiment according to the present disclosure Figure 1-2A flow chart of a method for using an electronic sensing system to detect a target gas. DETAILED DESCRIPTION

[0028] A detailed description of one or more embodiments of the disclosed apparatus and methods is presented herein by way of illustration and not limitation with reference to the accompanying drawings.

[0029] The resistive response of a printed chemi-resistive gas sensor on a flexible substrate may be affected by contaminants (e.g., other gases such as CO2 and CO) as well as environmental conditions (e.g., humidity). Therefore, careful calibration out of real-world environmental conditions is required as they may significantly affect the sensor's readings. Embodiments disclosed herein attempt to provide an electronic sensing system that can calibrate out contaminants to provide accurate target gas readings.

[0030] Figure 1-2 The schematic diagram illustrates an electronic sensing system 100 configured to detect a target gas while adjusting for possible contaminants in the gas. It should be appreciated that, although specific systems are defined separately in the schematic block diagram, each or any of these systems can be combined or separated in another manner via hardware and / or software. The electronic sensing system 100 can be utilized in conjunction with the operation of a transport refrigeration system such as, for example, a refrigerated truck, a refrigerated trailer, or a refrigerated container. The electronic sensing system 100 can also be utilized in conjunction with the operation of a commercial refrigeration system such as, for example, a refrigerated cabinet (e.g., a self-service refrigerated grocery cabinet with doors and without doors). In a transport refrigeration system or a commercial refrigeration system, the electronic sensing system 100 can be used as part of a refrigeration control system to adjust the environmental conditions of perishable goods (e.g., goods / stock / inventory) in order to control ventilation, humidity, gas temperature, and / or a contaminant scrubbing system or affect the control of the above. In one embodiment, the electronic sensing system 100 can be used to activate ventilation to reduce the concentration of the target gas around the electronic sensing system 100, or to warn a worker of potential damage to perishable goods.

[0031] In another embodiment, the electronic sensing system 100 may be utilized independently of a corresponding refrigeration system or commercial refrigeration system to alert personnel of potential spoilage of perishable goods or to increase or decrease ventilation rates.

[0032] The electronic sensing system 100 includes a printed circuit board 110 having a first side 112 and a second side 114 opposite the first side 112. In a non-limiting embodiment, the printed circuit board 110 can be composed of multiple layers of fiberglass and copper. Most of the components 120 of the electronic sensing system 100 can be located on the first side 112 of the printed circuit board 110 and the energy source 116 can be located on the second side 114 of the printed circuit board 110. The energy source 116 can be electrically connected to the components 120 on the first side 112 of the printed circuit board 110 and provide electrical energy to the components 120 on the first side 112 of the printed circuit board 110.

[0033] The energy source 116 of the electronic sensing system 100 is configured to supply electrical energy to the electronic sensing system 100. The energy source 116 of the electronic sensing system 100 is configured to supply electrical energy to at least one component 120 on the first side 112 of the electronic sensing system 100. The energy source 116 of the electronic sensing system 100 may also be configured to store electrical energy in an energy storage system 118, such as, for example, a battery system, a capacitor, or other energy storage systems known to those skilled in the art. The energy source 116 may also include an energy generation system 119 to generate electrical energy for the electronic sensing system 100. The energy generation system 119 may be an energy generation or power harvesting system, such as, for example, a solar panel, a radio frequency energy harvesting device, or other types of generators known to those skilled in the art. In another embodiment, the energy source 116 may also be located on the first side 112 of the printed circuit board 110.

[0034] The electronic sensing system 100 may include a system on chip 130, a sensor hub 150, a digital potentiometer 160, and a thermistor 180. The system on chip 130 may include a processor 132, a memory 134, a communication device 136, an analog-to-digital converter (ADC) 137, an I 2 C 138 and general purpose input and output (GPIO). In an embodiment, the processor 132 can be a 32-bit reduced instruction set computer processor. In an embodiment, the memory 134 is a 512kB flash memory. The ADC 137 can be a 12-bit ADC. In an embodiment, the communication device 136 can be a 2.4GHZ radio device. The communication device 136 can be capable of transmitting a wireless signal 202 to the external device 200. The wireless signal 202 can be a long-range wireless (e.g., LORA) or a short-range wireless (e.g., Bluetooth). The communication device 136 can be configured to transmit the target gas concentration to the external device 200 via the wireless signal 202.

[0035] The external device 200 may be a computing device capable of real-time analysis, such as, for example, a desktop computer, a laptop computer, a tablet computer, a smart phone, a smart watch, or a similar computing device known to those skilled in the art. Although not shown for simplicity, the external device 200 may include a processor and an associated memory, the memory including computer executable instructions that cause the processor to perform various operations when executed by the processor. The processor may be, but is not limited to, a single processor or multi-processor system of any architecture in a wide range of possible architectures, including a field programmable gate array (FPGA), a central processing unit (CPU), an application specific integrated circuit (ASIC), a digital signal processor (DSP), or a graphics processing unit (GPU) hardware arranged in a homogeneous or heterogeneous manner. The memory may be, but is not limited to, a random access memory (RAM), a read-only memory (ROM), or other electronic, optical, magnetic, or any other computer-readable medium.

[0036] ADC 137 can electrically connect the system on chip 130 to a thermistor 180. The thermistor 180 is configured to measure the external temperature of the electronic sensing system 100. The thermistor 180 can be a negative temperature coefficient (NTC) temperature sensing element off-board (connected to the actual printed chemical-resistive gas sensor via wires) that is used to measure the temperature of the sensor for calibration. The thermistor 180 can be configured to measure the off-board temperature. The temperature sensor 154 can be mounted on the printed circuit board 110 and can be used to measure the temperature of the printed circuit board 110 in order to compensate for thermal drift of the on-board electrical components.

[0037] I 2 C 138 can electrically connect the system on chip 130 to an on-board sensor hub 150. The on-board sensor hub 150 can include a humidity sensor 152 and a temperature sensor 154. The humidity sensor 152 is configured to detect the humidity of the gas on the board near and / or within the electronic sensing system 100. The temperature sensor 154 is configured to detect the temperature of the gas on the board near and / or within the electronic sensing system 100.

[0038] GPIO 139 can electrically connect the system on chip 130 to a multiplexer 170 having two inputs 172, 174 (also referred to as a first port 172 and a second port 174) and an output 176. The two inputs of the multiplexer 170 can be a target gas sensor 192 and a reference sensor 194. The target gas sensor 192 is configured to detect a target gas. The target gas can be an organic gas molecule or an inorganic gas molecule. The organic gas molecules can include, but are not limited to, ethylene, formaldehyde, methane, propylene, any specific or total volatile organic compound (VOC) count, any specific or total alcohol count, any specific or total aromatic compound count, etc. The inorganic gas molecules can include, but are not limited to, O2, CO, CO2, ammonia (NH3), SH2, etc. In an embodiment, the target gas can be ethylene. The target gas sensor 192 and the reference sensor 194 can be similar. For example, the reference sensor 194 is a printed chemi-resistive sensor similar to the target gas sensor 192, but without the gas sensing chemistry included in the target gas sensor 192. The reference sensor 194 may have a similar response to pollutants (e.g., CO and CO2) as the target gas sensor 192, but the reference sensor 194 will not respond to the target gas. Therefore, the readings from the reference sensor 192 can be used to eliminate the effects caused by the pollutants (CO and CO2).

[0039] The target gas sensor 192 is electrically connected to the multiplexer 170 through the first port 172 and the reference sensor 194 is electrically connected to the multiplexer 170 through the second port 174. The output 176 of the multiplexer 170 is electrically connected to the digital potentiometer 160 and the digital potentiometer 160 can be electrically connected to the I / O through the low pass filter 162, the amplifier 164 and the analog to digital converter 166. 2 C 138.

[0040] The digital potentiometer 160 may be a second resistor 412 within the resistance comparator 400. The resistance comparator may be a Wheatstone bridge, a Kelvin bridge, an ohmmeter, or any similar device known to those skilled in the art. In an embodiment, the resistance comparator 400 may be a Wheatstone bridge. The resistance comparator may include a power supply 410, a first junction A1, a second junction C1, a first intermediate junction B1, a second intermediate junction D1, a first resistor 411, a second resistor 412, a third resistor 413, a fourth resistor 414, and a galvanometer 420. The first resistor 411 may have a known resistance R1. The second resistor 412 may have a known resistance R2. The third resistor 413 may have a known resistance R3. The fourth resistor 414 may have an unknown resistance R xThe target gas sensor 192 may be the fourth resistor 414 of the resistance comparator 400. The resistance comparator 400 may be used to adjust the resistance R2 of the second resistor 412 (ie, the digital potentiometer 160) so that the resistance R2 of the second resistor 412 (ie, the digital potentiometer 160) is equal to the resistance R2 of the fourth resistor (ie, the target gas sensor 192). x As closely as possible. Until the resistance R2 of the second resistor 412 (ie, the digital potentiometer 160) matches the resistance R of the fourth resistor (ie, the target gas sensor 192). x Matching, the galvanometer 420 can generate a voltage V G , the voltage V G The resistor R2 of the second resistor 412 (ie, the digital potentiometer 160) can be amplified by the amplifier 164 to more accurately adjust the resistance R2 of the second resistor 412 (ie, the digital potentiometer 160). Figure 1-2 In the case of Figure 3 , a flow chart of a method, a method 300 of detecting a target gas, is illustrated according to an embodiment of the present disclosure. In an embodiment, the target gas may be ethylene. In an embodiment, the method 300 is performed by the electronic sensing system 100. At block 304, the processor 132 is initialized and the method 300 is initiated.

[0041] At block 306, the communication device 136 initiates an advertisement of the wireless signal 202. The communication device 136 may be configured to continuously advertise the wireless signal 202 once initiated at block 306. An advertisement is the communication device 136 announcing its presence to any nearby listening external devices 200 and if the advertisement is a connectable advertisement, this is an opportunity for the external device 200 to connect to the communication device 136. For example, the wireless signal 202 of the communication device 136 may be a Bluetooth signal. The external device 200 is configured to detect the wireless signal 202 and connect to the communication device 136. At block 308, it is determined whether the communication device 136 is already connected to the external device 200 via the wireless signal 202. If at block 308, it is determined that the communication device 136 is not already connected to the external device 200 via the wireless signal 202, the method 300 moves to block 310 and the processor 132, ADC 137, sensor hub 150, and thermistor 180 go to sleep. If at block 308 , it is determined that the communication device 136 has been connected to the external device 200 via the wireless signal 202 , the method 300 moves to block 312 and the multiplexer 170 is set to the first port 172 , which is in electrical communication with the target gas sensor 192 .

[0042] At block 314, a target gas measurement is obtained through the ADC 166 using the target gas sensor 192. The target gas measurement is detected by the target gas sensor 192 through a resistance measurement made by the target gas sensor 192. If the target gas concentration has changed, the resistance measurement of the target gas sensor 192 will change.

[0043] At block 320, it is determined whether the resistance of the target gas sensor 192 captured during the target gas measurement matches the resistance of the digital potentiometer 160. If at block 320, the resistance of the target gas sensor 192 captured during the target gas measurement matches, the method 300 moves to block 324. If at block 320, the resistance of the target gas sensor 192 captured during the target gas measurement does not match, the method 300 moves to block 316 if the resistance is too low, or to block 318 if the resistance is too high. At block 318, if the resistance is too high, the digital potentiometer 160 is increased. At block 316, if the resistance is too low, the digital potentiometer 160 is decreased.

[0044] Once the resistance of the target gas sensor 192 captured during the target gas measurement is matched at block 320, the method 300 moves to block 324 to check if the resistance of the reference sensor 194 matches the resistance of the digital potentiometer 160. At block 322, the multiplexer 170 is set to the second port 174, which is in electrical communication with the reference sensor 194.

[0045] At block 314, a measurement is obtained using the ADC 166 and the reference sensor 194. The measurement is detected by the reference sensor 194 through a resistance measurement made by the reference sensor 194.

[0046] At block 320, it is determined whether the resistance of the reference sensor 194 captured during the reference measurement matches the resistance of the digital potentiometer 160. If at block 320, the resistance of the reference sensor 194 captured during the reference measurement matches, the method 300 moves to block 324. If at block 320, the resistance of the reference sensor 194 captured during the reference measurement does not match, the method 300 moves to block 316 if the resistance is too low, or to block 318 if the resistance is too high. At block 318, if the resistance is too high, the digital potentiometer 160 is increased. At block 316, if the resistance is too low, the digital potentiometer 160 is decreased.

[0047] Once the resistance of the reference sensor 194 captured during the reference measurement is matched at block 320, the method 300 moves to block 324 where both the resistance of the reference sensor 194 and the resistance of the target gas sensor 192 should now match. At block 326, the on-board humidity is measured by the humidity sensor 152 and the on-board temperature is measured by the temperature sensor 154. The reference sensor 194 and the target gas sensor 192 should respond identically to humidity and temperature changes.

[0048] At block 328 , the external temperature is measured by the thermistor 180 .

[0049] At block 330, compensation is applied to the resistance captured by the target gas sensor 192 and the resistance captured by the reference sensor 194. Both the target gas sensor 192 and the reference sensor 194 are pre-calibrated based on the on-board humidity measured by the humidity sensor 152, the on-board temperature measured by the temperature sensor 154, and the external temperature measured by the thermistor 180. Ideally, the reference sensor 194 and the target gas sensor 192 should have the same response to humidity and temperature, but in real life this may be different due to the effects of the sensing chemistry and the fact that the printed substrates may not be exactly the same. From testing, the resistance response of the reference sensor 194 and the target gas sensor 192 to humidity and temperature may be generally much higher than the resistance response of the reference sensor 194 and the target gas sensor 192 to the target gas. Therefore, it may be necessary to compensate the readings of the reference sensor 194 and the target gas sensor 192 by the humidity detected by the humidity sensor 152 and the temperature detected by the temperature sensor 154.

[0050] At block 332 , the compensated resistance is then transmitted back to the external device 200 and the method may move back to block 312 to capture more resistance measurements.

[0051] At block 334, a target gas concentration is determined in response to the resistance of the target gas sensor 192 and the resistance of the reference sensor 194. For example, because the reference sensor 194 detects pollutants rather than the target gas, although the target gas sensor 192 detects both the target gas and the pollutants, a combination of the resistance of the target gas sensor 192 and the resistance of the reference sensor 194 may be used to determine the resistance. The resistance of the target gas sensor 192 used in determining the target gas concentration may be a compensated resistance, as described in block 330. The resistance of the reference sensor 194 used in determining the target gas concentration may be a compensated resistance, as described in block 330.

[0052] Although the above description has been described in a specific order Figure 3 The present invention provides a flow chart of the present invention, but it should be appreciated that the order of the steps may vary unless otherwise specifically required in the appended claims.

[0053] As described above, embodiments may take the form of processor-implemented processes and devices (such as processors) for practicing those processes. Embodiments may also take the form of computer program code, which includes instructions embodied in tangible media, such as network cloud storage devices, SD cards, flash drives, floppy disks, CD ROMs, hard drives, or any other computer-readable storage media, wherein when the computer program code is loaded into a computer and executed by the computer, the computer becomes a device for practicing the embodiments. Embodiments may also take the form of computer program code, such as whether stored in a storage medium, loaded into a computer and / or executed by a computer, or transmitted through a transmission medium, loaded into a computer and / or executed by a computer, or transmitted through a transmission medium (such as by electrical wiring or cables, by optical fibers, or via electromagnetic radiation), wherein when the computer program code is loaded into a computer and executed by a computer, the computer becomes a device for practicing the embodiments. When implemented on a general-purpose microprocessor, the computer program code segments configure the microprocessor to create a specific logic circuit.

[0054] The term "about" is intended to include the degree of error associated with the measurement of the particular quantity based on the equipment available at the time the application was filed.

[0055] The terms used herein are for the purpose of describing specific embodiments only and are not intended to limit the present disclosure. As used herein, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises and / or comprising" when used in this specification specify the presence of the described features, wholes, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components, and / or groups thereof.

[0056] Although the present disclosure has been described with reference to an exemplary embodiment or multiple embodiments, it will be appreciated by those skilled in the art that various changes may be made and equivalents may be substituted for its elements without departing from the scope of the present disclosure. In addition, many modifications may be made to adapt specific circumstances or materials to the teachings of the present disclosure without departing from its essential scope. Therefore, it is intended that the present disclosure is not limited to the specific embodiments disclosed as the best mode intended for carrying out the present disclosure, but that the present disclosure will include all embodiments falling within the scope of the claims.

Claims

1. An electronic sensing system for detecting a target gas located on a printed circuit board, the electronic sensing system comprising: a target gas sensor configured to detect a resistance of the target gas sensor; a reference sensor configured to detect a resistance of the reference sensor; a resistance comparator, the resistance comparator comprising a digital potentiometer, the resistance comparator being electrically connected to the target gas sensor and the reference sensor, wherein the digital potentiometer is configured to be adjusted to determine a first resistance in response to a resistance of the target gas sensor and to determine a second resistance in response to a resistance of the reference sensor, comprising: adjusting the resistance of the digital potentiometer according to the resistance of the target gas sensor when it is determined that the resistance of the target gas sensor captured during target gas measurement does not match the resistance of the digital potentiometer, and determining the first resistance in response to the resistance of the target gas sensor when it is determined that the resistance of the target gas sensor captured during target gas measurement matches the resistance of the digital potentiometer; and adjusting the resistance of the digital potentiometer according to the resistance of the reference sensor upon determining that the resistance of the reference sensor captured during the reference measurement does not match the resistance of the digital potentiometer, and determining the second resistance in response to the resistance of the reference sensor upon determining that the resistance of the reference sensor captured during the reference measurement matches the resistance of the digital potentiometer; and A system on a chip is in electronic communication with the resistance comparator, the system on a chip configured to determine a target gas concentration in response to the first resistance and the second resistance.

2. The electronic sensing system of claim 1, further comprising: A multiplexer electrically connects the resistance comparator to the target gas sensor and the reference sensor, wherein the multiplexer includes a first port electrically connected to the target gas sensor, a second port electrically connected to the reference sensor, and an output port electrically connected to the resistance comparator.

3. The electronic sensing system of claim 2, wherein the system on a chip further comprises a general purpose input output in electronic communication with the multiplexer.

4. The electronic sensing system of claim 1, further comprising: A humidity sensor is configured to detect humidity on board of the electronic sensing system.

5. The electronic sensing system of claim 1, further comprising: A temperature sensor is configured to detect an on-board temperature of the electronic sensing system.

6. The electronic sensing system of claim 4, wherein the system on a chip further comprises an I 2 C.

7. The electronic sensing system of claim 5, wherein the system on a chip further comprises an I 2 C.

8. The electronic sensing system of claim 4, wherein the system on a chip is configured to adjust the first resistor and the second resistor to compensate for on-board humidity.

9. The electronic sensing system of claim 5, wherein the system on a chip is configured to adjust the first resistance and the second resistance to compensate for the on-board temperature.

10. The electronic sensing system of claim 1, wherein the system on a chip further comprises an I2C chip in electronic communication with the resistance comparator. 2 C.

11. The electronic sensing system of claim 10, further comprising: Low pass filter; Amplifier; as well as Analog-to-digital converters, Wherein I 2 C is in electronic communication with the resistance comparator through the low pass filter, the amplifier and the analog to digital converter.

12. The electronic sensing system of claim 1, wherein the system on a chip further comprises: A communication device is configured to broadcast a wireless signal.

13. The electronic sensing system of claim 12, wherein the wireless signal is Bluetooth.

14. The electronic sensing system of claim 12, wherein the communication device is configured to transmit the target gas concentration to an external device via the wireless signal.

15. The electronic sensing system of claim 5, further comprising: A thermistor is configured to measure an off-board temperature, wherein the system-on-chip is configured to adjust the on-board temperature in response to the off-board temperature.

16. The electronic sensing system of claim 1, wherein the target gas is ethylene.

17. A method for detecting a target gas, the method comprising: Detecting the resistance of the target gas sensor; Detect the resistance of the digital potentiometer; adjusting the resistance of the digital potentiometer to a first resistance so that the first resistance of the digital potentiometer matches the resistance of the target gas sensor, comprising: adjusting the resistance of the digital potentiometer according to the resistance of the target gas sensor when it is determined that the resistance of the target gas sensor captured during the target gas measurement does not match the resistance of the digital potentiometer, and determining the first resistance in response to the resistance of the target gas sensor when it is determined that the resistance of the target gas sensor captured during the target gas measurement matches the resistance of the digital potentiometer; Detecting the resistance of the reference sensor; adjusting the resistance of the digital potentiometer to a second resistance so that the second resistance of the digital potentiometer matches the resistance of the target gas sensor, comprising: adjusting the resistance of the digital potentiometer according to the resistance of the reference sensor when it is determined that the resistance of the reference sensor captured during the reference measurement does not match the resistance of the digital potentiometer, and determining the second resistance in response to the resistance of the reference sensor when it is determined that the resistance of the reference sensor captured during the reference measurement matches the resistance of the digital potentiometer; and A target gas concentration is determined in response to the first resistance and the second resistance.

18. The method of claim 17, wherein before determining the target gas concentration in response to the first resistance and the second resistance, the method further comprises: Use humidity sensor to detect humidity on board; as well as The first resistor and the second resistor are adjusted in response to humidity on the board to compensate for humidity on the board.

19. The method of claim 17, wherein before determining the target gas concentration in response to the first resistance and the second resistance, the method further comprises: Use a temperature sensor to detect the temperature on the board; as well as The first resistor and the second resistor are adjusted in response to the on-board temperature to compensate for the on-board temperature.

20. The method of claim 17, wherein before determining the target gas concentration in response to the first resistance and the second resistance, the method further comprises: Use humidity sensor to detect humidity on board; Use a temperature sensor to detect the temperature on the board; as well as The first resistor and the second resistor are adjusted in response to the on-board humidity and the on-board temperature to compensate for the on-board humidity and the on-board temperature.

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