Gas sensor array comprehensive test system and method thereof

Abstract

The invention discloses a gas sensor array comprehensive test system and method, and belongs to the technical field of gas sensor testing. In order to realize the test of a sensor in a marine simulation environment, the device comprises a gas chamber, a fault trigger, a program-controlled gas injector, a vibration swing platform, a signal acquisition conditioning module, a data communication module and an upper computer, the air chamber is arranged on the vibration swing platform and is respectively connected with the fault trigger, the program control air injector and the signal acquisition and conditioning module, the data communication module is connected with the signal acquisition and conditioning module, and the data communication module is connected with the upper computer; the air chamber comprises a box body, a sealing pressure-resistant cover and a condensation dropper are mounted at the top end of the box body, the condensation dropper extends into the box body, and a sensor array, a monitoring sensor, a humidifier, a heater and a fan are arranged in the box body; the sensor array is connected with the signal acquisition board, and the condensation dropper is arranged above the sensor array; air injection holes are formed in the side faces of the air chambers. The device is used for sensor performance testing and fault simulation in the marine environment.

Description

Technical Field

[0001] The invention belongs to the technical field of gas sensor testing, and in particular relates to a gas sensor array comprehensive test system and method. Background Art

[0002] Methane in the atmosphere primarily originates from the ocean, the decomposition of organic matter, swamps, fossil fuels, animal digestion, and rice paddy bacteria. The ocean is a significant source of atmospheric methane emissions. Ocean testing typically involves collecting samples and conducting laboratory tests. However, this approach presents several drawbacks: During collection, transportation, and storage, changes in the state and characteristics of the original sample due to factors such as light, vibration, and pressure are unavoidable. This method also requires a long time to collect and test, with the sampling and testing time sometimes lags by as much as half a month due to voyages, making it impossible to rapidly measure dissolved methane concentrations on the seafloor. The sampling process is fragmented and discontinuous, making it impossible to achieve long-term, continuous, and real-time observations of a specific area, making it difficult to obtain dynamic information on the seafloor. With the advancement of methane sensor technology, in-situ detection of methane gas directly in the ocean has become possible.

[0003] Detecting the spatiotemporal distribution of marine methane relies on methane sensors. As electromechanical systems, methane sensors possess common mechanical components, Joule temperature fields, sensitive resistance changes, and current and voltage circuits. Detecting methane in marine environments requires consideration of environmental interference, particularly when methane sensors are mounted on underwater vehicles for on-board testing. Sensor failures are common due to the harsh environment, including the vehicle's rocking and pitching, engine and propeller vibrations and impacts, and the high humidity and fluctuating temperatures of the ocean. An effective testing system is lacking to address key issues such as sensor performance testing, simulated fault triggering, reliability testing, and prediction. Summary of the Invention

[0004] The problem to be solved by the present invention is to realize the test of sensors in an ocean simulation environment, and propose a gas sensor array comprehensive test system and method.

[0005] To achieve the above object, the present invention is implemented through the following technical solutions:

[0006] A comprehensive test system for a gas sensor array includes a gas chamber, a fault trigger, a programmable gas injector, a vibration and rocking platform, a signal acquisition and conditioning module, a data communication module, and a host computer;

[0007] The air chamber is arranged on a vibration and rocking platform, and the air chamber is respectively connected to a fault trigger, a programmable gas injector, a signal acquisition and conditioning module, and a data communication module. The signal acquisition and conditioning module is connected to the data communication module, and the data communication module is connected to a host computer.

[0008] The air chamber includes a box body, a sealed pressure-resistant cover and a condensation dripping pipe are installed on the top of the box body, and the condensation dripping pipe extends into the box body. The box body is provided with a sensor array, a monitoring sensor, a humidifier, a heater, and a fan; the sensor array is respectively connected to a fault trigger and a signal acquisition and conditioning module, and the monitoring sensor is connected to a data communication module;

[0009] The sensor array is connected to a signal acquisition board, and the condensation dripping pipe is arranged above the sensor array;

[0010] The side of the gas chamber is provided with a gas injection hole for connecting a program-controlled gas injector;

[0011] The program-controlled gas injector is used to inject a certain concentration range of gas into the gas chamber;

[0012] The fault trigger is used to simulate the on-off sudden fault of the connection between the sensor functional components, the sensor sensitive resistor fault, the condensation dropper is used to simulate the condensation blockage fault, and the programmable DC power supply is used to simulate the working voltage and heating voltage sudden fault;

[0013] The vibrating and rocking platform is used to realize the tilting, rocking and vibration actions of the air chamber.

[0014] Furthermore, the number of monitoring sensors is 5, including a temperature sensor, a humidity sensor, an air pressure sensor, a vibration sensor, and a tilt angle sensor. The sensor array includes 9 semiconductor gas sensors. A ceramic tube with a heating wire is placed inside the semiconductor sensor; the ceramic tube is coated with a sensitive material, and after the heating wire of the ceramic tube with the heating wire is energized and heated, the temperature of the ceramic tube rises in the range of 200°C to 450°C.

[0015] Furthermore, the fault trigger simulates the on-off sudden fault of the connection between the functional components of the sensor, including connecting the programmable relay in series with the heating wire connection end and the signal lead end of the sensor array, and using the on and off of the programmable relay to simulate the on or off or virtual on and virtual off of the sensor array connection;

[0016] The fault trigger simulates the sensor sensitive resistance fault, including connecting a programmable potentiometer in series to the signal lead end of the sensor array, and using the resistance change of the programmable potentiometer to simulate the sudden fault of the sensitive body cracking, sensitive body warping, and sensitive film shedding of the semiconductor sensor in the sensor array.

[0017] Furthermore, the programmable gas injector includes installing syringes of different volume specifications on the linear slide of the stepping motor, and controlling the injection volume and injection speed of the syringe by controlling the step length of the linear slide and the injection action interval. The number of the syringes is 1 to 5, and the needles of the 1 to 5 syringes are connected to the injection holes of the gas chamber through the injection tubes, so as to achieve the generation of a mixed concentration of up to 5 different gases. The programmable gas injector uses 100% pure gas to generate a concentration gas with a lower limit of 5ppb and an upper limit of 8vol% to inject into the gas chamber, and the injection action control time interval is adjustable in the range of 1s to 3h.

[0018] Furthermore, the heater and humidifier can control the temperature and humidity changes of the microenvironment in the air chamber.

[0019] Furthermore, the vibration and rocking platform utilizes a rotating motor and an additional eccentric wheel mechanical conversion device installed on the bracket to achieve the tilting and rocking movement of the air chamber; the vibration and rocking platform utilizes a vibration motor installed on the bracket to achieve the vibration movement of the air chamber.

[0020] Furthermore, the host computer receives signals from the data communication module, receives and collects temperature, humidity, air pressure, vibration, swing, and gas concentration information data, outputs signals through the sensor array and extracts characteristic information for data processing, and the signal acquisition board realizes the connection between the sensor array and the signal acquisition and conditioning module.

[0021] A comprehensive test method for a gas sensor array is implemented based on a comprehensive test system for a gas sensor array. Before testing, semiconductor sensors are mounted on a signal acquisition board to form a sensor array. The sensors are powered on to stabilize the sensors. The method first tests the operating status of a fan for accelerating gas diffusion, a monitoring sensor for environmental information monitoring, a heating coil for changing ambient temperature, a humidifier for changing ambient humidity, and a condensation dropper. After the tests are normal, a sealed pressure-resistant cover is installed on the gas chamber.

[0022] Then, the blower is modulated to work state, the standard heating voltage and standard working voltage of the semiconductor sensor are adjusted, and after the programmable gas injector injects gas from the gas injection hole on the left side of the gas chamber, the sensor array outputs the signal to the signal acquisition and conditioning module for signal acquisition;

[0023] During the test, the gas concentration, injection rate and injection interval of the gas chamber are controlled by a programmable gas injector.

[0024] Furthermore, the method for the signal acquisition and conditioning module to acquire signals and adjust sensitivity includes the following steps:

[0025] S1. Set up the sensor signal adjustment circuit of the signal acquisition and conditioning module, including the sensitive resistor Rs and the programmable potentiometer , adjustable resistor R L , sampling resistor R0, the sampling resistor R0, the adjustable resistor R L , programmable potentiometer , sensitive resistor Serial connection, the programmable potentiometer The high potential end of the sensitive resistor Rs connected in series in the output circuit of the semiconductor sensor;

[0026] The sensor signal adjustment circuit adopts the voltage division method, in which a program-controlled power supply is used to provide the working voltage for the semiconductor sensor. Under normal conditions, the working voltage of the semiconductor sensor is 5V±0.05V, using DC mode. To test the circuit voltage, the load resistor output voltage is proportional to the sensor sensitive resistance. The relationship is:

[0027]

[0028] When the sensitive resistor When the load resistance decreases, the output voltage Increase, by collecting the load resistance voltage Reflects the sensor's response to gas and is used for gas-sensitive characteristics testing and data analysis;

[0029] The resistance adjustment range of the programmable potentiometer is 0 to 501KΩ;

[0030] S2. Power on the semiconductor sensor and determine the zero output.

[0031] S3. Place the semiconductor sensor in the gas concentration to be measured. When the semiconductor sensor outputs a steady-state value, adjust the programmable potentiometer. Output, as the potentiometer output resistance increases, the sensor sensitivity decreases. When the potentiometer is adjusted to a certain resistance, the sensitivity of the sensor under the measured gas concentration is obtained. The sensor sensitivity S is defined as the sensor output voltage under the action of unit methane volume fraction C. The change is expressed as:

[0032] .

[0033] Furthermore, in step S1, the semiconductor sensor heating voltage V h The setting method is:

[0034] A programmable power supply is used to provide heating voltage for the semiconductor sensor heating wire;

[0035] Under normal conditions, the semiconductor sensor heating wire operates at 5V±0.05V, and the semiconductor sensor detects single methane gas;

[0036] Under normal conditions, the semiconductor sensor heating wire operates at 5V±0.05V, and the semiconductor sensor detects single hydrogen sulfide gas;

[0037] Under the condition of known methane and hydrogen sulfide mixed gas, the programmable DC power supply is used to adjust the semiconductor sensor heating wire to work from 5V to 4V. At this time, the semiconductor sensor will show that it is insensitive to methane and only sensitive to hydrogen sulfide gas, thereby realizing the detection of hydrogen sulfide gas.

[0038] Furthermore, the conditions for simulating the swinging are to set the swinging frequency to 0.05 Hz to 1 Hz and the swinging angle to -35° to 35°.

[0039] Beneficial effects of the present invention:

[0040] The gas sensor array comprehensive test system described in the present invention can realize the sensitivity performance test of the sensor array. By controlling the heating voltage of the sensor and quickly picking up the sampling signal, it can meet the concentration value, sensitivity, linearity, hysteresis, repeatability, stability, reliability and other tests of methane gas and interfering gas.

[0041] The gas sensor array comprehensive test system described in the present invention targets the actual operating environmental parameters of marine vehicles, simulates environmental stress conditions such as temperature, humidity, vibration, tilt, and swing, and detects system status information through standard sensors.

[0042] The gas sensor array comprehensive test system described in the present invention is designed to test typical sensor failure modes, simulating fault excitations such as open solder joints, cold solder joints, sensitive body detachment, condensation blockage, and double fault superposition. It utilizes automation technology to implement program control of fault occurrence.

[0043] The gas sensor array comprehensive test system described in the present invention realizes extremely wide range control of gas concentration in the measurement chamber, injection rate control, and automatic control of injection interval through a programmable gas injector to ensure the gas distribution range and precise control of gas distribution of the sensor static test system.

[0044] The gas sensor array comprehensive test system described in the present invention solves technical problems in marine methane detection projects, expands gas sensor performance testing and fault testing methods, and has very important engineering value in promoting the use of marine methane detection instruments and improving gas detection technology in complex environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1This is a schematic structural diagram of a gas sensor array comprehensive test system according to the present invention;

[0046] Figure 2 This is a schematic structural diagram of a gas chamber of a comprehensive test system for a gas sensor array according to the present invention;

[0047] Figure 3 A circuit diagram of a sensor signal adjustment circuit of a gas sensor array comprehensive test system according to the present invention;

[0048] Figure 4 This is a schematic diagram of the vibration structure of a vibration swing platform in a gas sensor array comprehensive test system according to the present invention;

[0049] Figure 5 This is a methane test curve before and after heating voltage modulation of a gas sensor array comprehensive test system according to the present invention;

[0050] Figure 6 This is a hydrogen sulfide gas test curve before and after heating voltage modulation of a gas sensor array comprehensive test system described in the present invention. DETAILED DESCRIPTION

[0051] In order to make the objectives, technical solutions, and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain the present invention and are not intended to limit the present invention. That is, the specific embodiments described herein are only some embodiments of the present invention, not all embodiments. Generally, the components of the specific embodiments of the present invention described and illustrated in the drawings herein can be arranged and designed in various different configurations, and the present invention can also have other embodiments.

[0052] Therefore, the following detailed description of the specific embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention as claimed, but is merely representative of selected specific embodiments of the present invention. All other specific embodiments obtained by those skilled in the art based on the specific embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0053] In order to further understand the content, features and effects of the present invention, the following specific embodiments are given as examples, and the attached Figure 1 -Attached Figure 6 The detailed instructions are as follows: Specific implementation method one:

[0055] A comprehensive test system for a gas sensor array includes a gas chamber 1, a fault trigger 2, a programmable gas injector 3, a vibration and rocking platform 4, a data communication module 5, a signal acquisition and conditioning module 6, and a host computer 7;

[0056] The gas chamber 1 is arranged on a vibrating and rocking platform 4, and is respectively connected to a fault trigger 2, a programmable gas injector 3, a data communication module 5, and a signal acquisition and conditioning module 6. The signal acquisition and conditioning module 6 is connected to the data communication module 5, and the data communication module 5 is connected to a host computer 7.

[0057] The air chamber 1 includes a box body 1-1, a sealed pressure-resistant cover 1-2 and a condensation dripping pipe 1-3 are installed on the top of the box body 1-1, and the condensation dripping pipe 1-3 extends into the box body 1-1. The box body 1-1 is provided with a sensor array 1-4, a monitoring sensor 1-5, a humidifier 1-7, a heater 1-8, and a fan 1-9. The sensor array 1-4 is respectively connected to a fault trigger 2, a data communication module 5, and a signal acquisition and conditioning module 6, and the monitoring sensor 1-5 is connected to the data communication module 5.

[0058] The sensor array 1-4 is connected to the signal acquisition board 1-6, and the condensation dripping pipe 1-3 is arranged above the sensor array 1-4;

[0059] The side of the gas chamber 1 is provided with a gas injection hole for connecting a program-controlled gas injector 3;

[0060] The program-controlled gas injector 3 is used to inject a certain concentration range of gas into the gas chamber;

[0061] The fault trigger 2 is used to simulate the on-off sudden fault of the connection between the sensor functional components, the sensor sensitive resistor fault, the condensation dropper is used to simulate the condensation blockage fault, and the programmable DC power supply is used to simulate the working voltage and heating voltage sudden fault;

[0062] The vibrating and rocking platform 4 is used to achieve the tilting, rocking and vibration of the air chamber 1 .

[0063] Furthermore, the number of the monitoring sensors 1-5 is 5, including a temperature sensor, a humidity sensor, an air pressure sensor, a vibration sensor, and a tilt angle sensor. The sensor array 1-4 includes 9 semiconductor gas sensors, and a ceramic tube with a heating wire is placed inside the semiconductor sensor; the ceramic tube is coated with a sensitive material, and after the heating wire of the ceramic tube with the heating wire is energized and heated, the temperature rise range of the ceramic tube is 200°C to 450°C.

[0064] Furthermore, the fault trigger 2 simulates the on-off sudden fault of the connection between the sensor functional components, including connecting the programmable relay in series with the wire connection end and the signal lead end of the sensor array 1-4, and using the on and off of the programmable relay to simulate the connection of the sensor array 1-4.

[0065] The fault trigger 2 simulates the sensor sensitive resistance fault by connecting a programmable potentiometer in series to the signal lead end of the sensor array 1-4, and uses the resistance change of the programmable potentiometer to simulate the sudden fault of the sensitive body cracking, sensitive body warping, and sensitive film shedding of the semiconductor sensor in the sensor array 1-4.

[0066] Furthermore, the fault trigger 2 simulates the sensor working voltage fault and the heating voltage fault, including loading the working voltage output by the first programmable power supply to both ends of the sensitive resistor and the sampling resistor of the sensor array 1-4 ( Figure 3 The voltage change of the programmable power supply is used to simulate the sudden change of the working voltage in the sensor array 1-4. The heating voltage output by the second programmable power supply is also applied to both ends of the heating wire of the sensor array 1-4 ( Figure 3 Vh in), using the heating voltage change output by the programmable power supply to simulate the heating voltage mutation fault in the sensor array 1-4;

[0067] Furthermore, the programmable gas injector 3 includes installing syringes of different volume specifications on the linear slide of the stepping motor, and controlling the injection volume and injection speed of the syringe by controlling the step length of the linear slide and the injection action interval. The number of the syringes is 1 to 5, and the needles of the 1 to 5 syringes are connected to the injection holes of the gas chamber 1 through the injection tube. The programmable gas injector 3 uses 100% pure gas to generate a concentration gas with a lower limit of 5ppb and an upper limit of 8vol% to inject into the gas chamber. The injection action control time interval is adjustable in the range of 1s to 3h.

[0068] Furthermore, the vibration and rocking platform 4 realizes the tilting and rocking motion of the air chamber 1 by installing a rotating motor and an additional eccentric wheel mechanical conversion device on the bracket, and realizes the vibration motion of the air chamber 1 by installing a vibration motor on the bracket.

[0069] Furthermore, the host computer 7 receives the signal from the data communication module 5, receives the collected temperature, humidity, air pressure, vibration, swing, and gas concentration information data, collects the output signals of the sensor array 1-4 and extracts characteristic information for data processing, and the signal acquisition board 1-6 realizes the connection between the sensor array 1-4 and the signal acquisition and conditioning module 6.

[0070] Furthermore, semiconductor gas sensor calibration is a crucial step in sensor array testing. Static calibration methods offer stability, reliability, and excellent repeatability. A semiconductor sensor is placed in a standard gas chamber. Pure gas to be measured is injected into the chamber based on the known internal volume. The standard gas concentration is then converted to the standard gas concentration. When the standard gas concentration is applied to the sensor, an analog signal is generated at the output, establishing a corresponding input-output relationship for the standard gas concentration, thus achieving sensor calibration.

[0071] Furthermore, the programmable gas injector works as follows:

[0072] A: Use 1ml, 3ml, and 5ml gas injection tubes to extract pure hydrogen sulfide gas from the hydrogen sulfide bag, and use 5ml, 20ml, 50ml, 100ml, 500ml, and 1000ml gas injection tubes to extract pure methane gas from the methane bag.

[0073] B: According to the designed gas concentration ratio of hydrogen sulfide and methane, take the hydrogen sulfide injection pipe and the methane injection pipe respectively, and install them on the linear slide of the stepper motor. The linear slide can carry 5 injection pipes.

[0074] C: Start the switch power supply, turn on the controller, turn on the driver, drive the stepper motor, and adjust the initial position of the hydrogen sulfide injection pipe and the methane injection pipe on the linear slide.

[0075] D: Set the linear slide step length and air injection interval on the controller. The air injection interval is adjustable from 1s to 3h.

[0076] E: Start the control program, the hydrogen sulfide injection pipe and methane injection pipe on the linear slide will be injected into the gas chamber, and the mixed gas concentration is set in advance.

[0077] Furthermore, it can be configured with single methane gas, single hydrogen sulfide gas, or a mixture of methane and hydrogen sulfide gas. Since the linear slide can be equipped with five gas injection tubes, it can also be configured with any other five gases, either a single gas, or a mixture of two, three, four, or five gases.

[0078] Calculation of the accuracy of a programmable gas injection device: Given a gas chamber volume of 20 L, a linear slide control step accuracy of 10 μm, and a 1 ml gas injector effective length of 100 mm, if the linear slide advances with a control step length of 10 μm, the amount of gas injected by the 1 ml gas injector is:

[0079] [10um / (100×1000um)×1ml = 0.0001ml

[0080] The injected gas concentration accuracy is:

[0081] 0.0001ml / (20×1000ml)= 0.000000005=0.005×10 6 =0.005ppm=5ppb.

[0082] According to the linear slide, a maximum of three gas injection tubes (1000ml, 500ml, and 100ml) can be installed simultaneously. If the three gas injection tubes are loaded with the same gas, the maximum gas concentration that can be formed in the 20L gas chamber is:

[0083] (1000ml+500ml+100ml) / 20L=1600ml / 20000ml=0.08=8%

[0084] That is, the programmable gas injection device can achieve gas generation with a maximum concentration of 8%.

[0085] Therefore, the programmable gas injection device can use 100% pure gas to achieve a gas concentration range with a lower limit of 5ppb and an upper limit of 8vol%, a control accuracy of 5ppb, and an injection action interval adjustable from 1s to 3h.

[0086] The comprehensive gas sensor array test system described in this embodiment ensures precise control of gas distribution in the static sensor test system. A programmable gas injector is used to achieve a wide range of gas generation with a lower limit of 5 ppb and an upper limit of 8 vol%. The injection action is controllable and the interval is adjustable from 1s to 3h. At the same time, the system can simultaneously heat and acquire signals from a 2×3 array, and can normally perform sensitivity performance tests on the 2×3 array, including single gas tests and multi-gas mixture tests, to meet the concentration, sensitivity, linearity, hysteresis, repeatability, stability, and reliability tests of methane gas and interfering gases.

[0087] The comprehensive test system for a gas sensor array described in this embodiment targets typical failure modes of sensors and uses semi-physical simulation to simulate the triggering of single failure modes such as disconnection of sensor heating wire, poor soldering of heating wire, disconnection of signal lead, poor soldering of signal lead, cracking of sensitive body, detachment of sensitive membrane, condensation blockage of ventilation membrane, sudden change in working voltage, and sudden change in heating voltage, covering every sensor in the 2×3 array.

[0088] A comprehensive gas sensor array test system described in this embodiment is capable of simultaneously performing fault superposition excitation on a 2×3 array. The excitation modes include 10 dual-fault superposition modes, including: heater wire disconnection + signal lead cold solder joint, heater wire disconnection + signal lead disconnection, heater wire disconnection + sensitive body cracking, heater wire disconnection + sensitive film detachment, heater wire disconnection + condensation blockage, heater wire cold solder joint (cold connection, i.e., disconnected and connected) + signal lead cold solder joint, heater wire cold solder joint (cold connection, i.e., disconnected and connected) + signal lead disconnection, heater wire cold solder joint (cold connection, i.e., disconnected and connected) + sensitive body cracking, heater wire cold solder joint (cold connection, i.e., disconnected and connected) + sensitive film detachment, heater wire cold solder joint (cold connection, i.e., disconnected and connected) + condensation blockage, thereby achieving program control over the occurrence of faults.

[0089] The gas sensor array comprehensive test system described in this embodiment can simulate the actual operating environmental parameters of the methane sensor working on the marine carrier, simulate environmental stress conditions such as temperature, humidity, vibration, and swing, and realize system status information detection through standard sensors.

[0090] The gas sensor array comprehensive test system described in this embodiment can simulate the swaying conditions of methane sensors during operation, achieving large-angle sway loads on the sensor on a carrier. Based on the engineering context, the carrier is subject to waves and currents, with a sway angle of ±25° and an adjustable frequency of 0.05Hz to 1Hz (period 1s to 20s). The system also simulates the vibration conditions of the sensor during operation and achieves vibration loads on the sensor on the carrier. Based on the engineering context, the vibration spectrum of the carrier's turbofan propeller has a frequency of 0 to 10kHz and an amplitude of 0 to 1.5mm.

[0091] This embodiment describes a comprehensive gas sensor array test system. A lower-level computer system collects sensor data in real time and transmits it to a higher-level computer via a data acquisition serial port. This system uses a human-computer interface to display, store, and perform early warning and alarm functions. The system's sampling frequencies are selectable: 1 kHz, 500 Hz, or 100 Hz. Specific implementation method two:

[0093] A gas sensor array comprehensive test method is implemented based on a gas sensor array comprehensive test system described in the first embodiment;

[0094] Before testing, semiconductor sensors are installed on the signal acquisition board to form a sensor array. Power is then turned on to allow the sensors to reach a stable state. The working status of the fan used to accelerate gas diffusion, the monitoring sensor used to monitor environmental information, the heating coil used to change the ambient temperature, the humidifier used to change the ambient humidity, and the condensation dropper are tested. Once all tests are normal, a sealed pressure-resistant cover is installed on the gas chamber.

[0095] Then, the blower is modulated to work state, the standard heating voltage and standard working voltage of the semiconductor sensor are adjusted, and after the program-controlled gas injector injects gas from the hole on the left side of the gas chamber, the sensor array outputs the signal to the signal acquisition and conditioning module for signal acquisition;

[0096] During the test, the gas concentration, injection rate and injection interval of the gas chamber are controlled by a programmable gas injector.

[0097] Furthermore, the method for adjusting the sensitivity of the signal acquisition and conditioning module includes the following steps:

[0098] S1. Set up the sensor signal adjustment circuit of the signal acquisition and conditioning module, including the sensitive resistor Rs and the programmable potentiometer , adjustable resistor R L , sampling resistor R0, the sampling resistor R0, the adjustable resistor R L , programmable potentiometer , sensitive resistor Serial connection, the programmable potentiometer The high potential end of the sensitive resistor Rs connected in series in the output circuit of the semiconductor sensor;

[0099] Furthermore, in step S1, the semiconductor sensor heating voltage V h The setting method is:

[0100] A programmable power supply is used to provide heating voltage for the semiconductor sensor heating wire;

[0101] Under normal conditions, the semiconductor sensor heating wire operates at 5V±0.05V, and the semiconductor sensor detects single methane gas;

[0102] Under normal conditions, the semiconductor sensor heating wire operates at 5V±0.05V, and the semiconductor sensor detects single hydrogen sulfide gas;

[0103] Under known methane and hydrogen sulfide mixed gas conditions, the programmable DC power supply is used to adjust the semiconductor sensor heating wire to work at 5V to 4V. At this time, the semiconductor sensor will show that it is insensitive to methane and only sensitive to hydrogen sulfide gas, thereby realizing hydrogen sulfide gas detection. Figure 5 and Figure 6 As shown;

[0104] Semiconductor gas sensors have poor selectivity and cross-sensitivity, making them a general-purpose sensor. In addition to precious metal doping, temperature modulation is another method for improving selectivity. Different gases have different optimal adsorption temperatures on the surface of the gas-sensitive material, and the rate of reaction with adsorbed oxygen also depends on temperature. At different temperatures, the adsorption rate and adsorption state of oxygen on the surface of the gas-sensitive material vary, resulting in different initial resistances in the sensor, which in turn affects the final gas-sensitive resistance. By properly selecting the heating voltage amplitude and cycle, the sensor can achieve selective sensitivity to different gases. For example, the MQ series sensor has good sensitivity to both methane and hydrogen sulfide at a heating voltage of 5V. At a heating voltage of 4V, it is almost insensitive to methane, but has measurable sensitivity to hydrogen sulfide. To this end, the sensor heating voltage is adjusted to achieve selective detection of different gases.

[0105] The sensor signal adjustment circuit adopts the voltage division method, in which a program-controlled power supply is used to provide the working voltage for the semiconductor sensor. Under normal conditions, the working voltage of the semiconductor sensor is 5V±0.05V, using DC mode. To test the circuit voltage, the load resistor output voltage is proportional to the sensor sensitive resistance. The relationship is:

[0106]

[0107] When the sensitive resistor When the load resistance decreases, the output voltage Increase, by collecting the load resistance voltage Reflects the sensor's response to gas and is used for gas-sensitive characteristics testing and data analysis;

[0108] The resistance adjustment range of the programmable potentiometer is 0 to 501KΩ;

[0109] Semiconductor sensors are only gas-sensitive when heated to high temperatures. Therefore, a heating wire is required to maintain a high-temperature environment during operation. The sensor's sensitivity and selectivity to the measured gas are significantly affected by the heating temperature, which in turn is related to the heating voltage. By controlling the heating voltage, the sensor can operate in different temperature environments. Different gases have optimal operating temperatures, and adjusting the heating voltage allows for adjustments in sensor selectivity.

[0110] Under constant working temperature conditions, the sensitive resistance of the gas sensor mainly depends on the grain boundary barrier and bulk resistance, and is also affected by the type of sensitive material, barrier size, grain contact state, and grain diameter. At different temperatures, the adsorption rate and adsorption state of the detected gas and oxygen in the air on the surface of the sensitive material are quite different. This causes the adsorption and desorption rate of the detected gas on the surface of the sensitive material and the reaction rate with the adsorbed oxygen to be different, further affecting the change of the sensor's sensitive resistance. The gas sensor's sensitive resistance is also a function of temperature. The sensor's sensitive resistance R is related to the barrier. There is the following relational expression:

[0111]

[0112] Where g is a constant determined by the geometric characteristics of the semiconductor, is the electron mobility, k is the Boltzman constant, T is the sensor operating temperature, is the grain boundary barrier;

[0113] From the above formula, it can be seen that when the working temperature increases, the sensitive resistance of the sensor decreases, and vice versa. Of course, the temperature change of the air environment will also affect the working temperature of the sensor, resulting in and Sensor performance is affected by changes in ambient temperature. Different gases have different optimal adsorption temperatures on the surface of sensitive materials, and the rates of oxygen adsorption reactions also vary. Based on this characteristic, the sensor can be modulated at different heating voltages and the heating temperature field can be appropriately selected to control the sensor's selective sensitivity to only certain gases at this temperature. This temperature modulation technology provides a solution for improving sensor selectivity.

[0114] S2. Power on the semiconductor sensor and determine the zero output.

[0115] S3. Place the semiconductor sensor in the gas concentration to be measured. When the semiconductor sensor outputs a steady-state value, adjust the programmable potentiometer. Output, as the potentiometer output resistance increases, the sensor sensitivity decreases. When the potentiometer is adjusted to a certain resistance, the sensitivity of the sensor under the measured gas concentration is obtained. The sensor sensitivity S is defined as the sensor output voltage under the action of unit methane volume fraction C. The change is expressed as:

[0116] ;

[0117] Furthermore, through the equation established by sensitivity S, it can be known that in the clean air state, the series connection A resistance value will reduce the sensitivity S, thereby achieving sensor sensitivity adjustment. The benefit of this invention is that it can achieve moderate sensitivity adjustment for high-sensitivity sensors, facilitating the connection with secondary instruments. For sensor arrays, it can achieve output differentiation for sensors of the same type. For MQ series semiconductor sensors, it can achieve a change of 100% to 10% of the normal sensitivity value;

[0118] Furthermore, the conditions for simulating the swinging are to set the swing frequency to 0.05 Hz to 1 Hz and the swing angle to .

[0119] Furthermore, the gas sensor array comprehensive test method includes a sensitivity performance test of the sensor array; a state information test of the gas sensor array comprehensive test system by monitoring the sensors under the actual operating environmental parameters of the marine vehicle and one or more of the environmental stress conditions of temperature, humidity, vibration, tilt, and sway; and an excitation test simulating the sensor array's solder joint opening, solder joint deficiency, sensitive body detachment, condensation blockage, and double fault superposition.

[0120] Furthermore, the state information test of the gas sensor array comprehensive test system is conducted by monitoring the sensors under the actual working environmental parameters of the ocean carrier and simulating one or more environmental stress conditions such as temperature, humidity, vibration, tilt and swing: the environmental stress loading function of the ocean detection working condition: including air chamber tilt, air chamber swing, air chamber vibration, air chamber internal temperature rise, air chamber internal humidity rise, etc., mainly simulating the actual working environmental stress parameters of the ocean carrier of the sensor array. When the air chamber tilt and swing stress occur, a swing motor and a swing arm are designed. The swing motor can directly drive the swing arm load air chamber to realize reciprocating swing, and the air chamber tilt and air chamber swing are realized by using a rotating motor through an additional eccentric wheel mechanical conversion device. To simulate the wave motion cycle, the swing frequency is designed to be 0.05 Hz~1Hz, and the swing angle is 0~ . To prevent vibration stress in the air chamber, a vibration motor assembly was designed, which mainly includes a vibration motor, a controller module, and a power supply. The vibration motor consists of an electric motor, an eccentric block, and a bearing. It converts electrical energy into mechanical vibration energy by generating vibration force. Due to the centrifugal force of the eccentric block, the motor generates vibration force, which is transmitted to the sensor in the air chamber, thus realizing environmental vibration stress loading. In order to increase the temperature and humidity in the air chamber, a heating coil and a humidifier are designed to achieve temperature and humidity control in the air chamber.

[0121] Furthermore, the following are the instructions for simulating the sensor array's excitation tests for solder joint opening, solder joint deficiency, sensitive element detachment, condensation blockage, and double fault superposition:

[0122] A On-off sudden fault mode trigger: uses the on and off of the programmable relay to simulate the on or off of the sensor connection. The programmable relay is connected in series with the heating end and the signal end of the semiconductor sensor to simulate 10 double fault superposition modes of the semiconductor sensor, such as the heating wire disconnection or cold soldering, signal lead disconnection or cold soldering, electrode ring disconnection or cold soldering, solder joint disconnection or cold soldering, and each sensor functional part. The on-off sudden fault mode is triggered.

[0123] B. Sensor sensitive resistance failure mode trigger: Design a programmable potentiometer module, connect the programmable potentiometer in series to the signal end of the semiconductor sensor, and use the resistance change of the programmable potentiometer to simulate sudden failures of the semiconductor sensor such as cracking of the sensitive body, warping of the sensitive body, and shedding of the sensitive membrane.

[0124] C. Condensation trigger: Primarily composed of a condensation generator module, this condensation generator consists of a 2x3 array of water-filled droppers, located on and sealed to the upper cover of the air chamber. When condensation occurs, simply squeeze the rubber hose of the dropper to force water out. Controlling the force creates droplets of varying sizes, which then form condensation on the sensor's splash-proof housing. When the water droplets completely soak the waterproof, breathable membrane, they block gas exchange inside and outside the sensor, causing condensation blockage.

[0125] The comprehensive test system has the function of environmental information detection: the environmental information detection sensor is composed of a standard temperature sensor, a humidity sensor, an air pressure sensor, a vibration acceleration sensor, and a MEMS gyroscope sensor, which can realize real-time detection of stress information such as temperature, humidity, air pressure, vibration, inclination, and swing in the gas test chamber.

[0126] Furthermore, the vibration of the vibration rocking platform is achieved as follows Figure 4As shown, the experimental system primarily consists of an experimental system stand, a vibration motor, an amplifier, a controller submodule, a digital display, a knob, and an AC / DC unit. The vibration motor, as an electric drive device, converts electrical energy into mechanical vibration energy by generating vibration force. It consists of an electric motor, an eccentric weight, and bearings. When powered on, the eccentric weight is fixed to the motor shaft and rotates at high speed. The centrifugal force of the eccentric weight generates vibration force in the motor, which is transmitted to the sensor in the sensor test chamber, thereby applying environmental vibration stress. The bearings support the rotation of the motor shaft and reduce friction and vibration noise. The housing protects the motor and vibration device and also provides support for mounting and installation. The vibration motor has a simple and reliable structure and high conversion efficiency from electrical energy to mechanical vibration energy. By adjusting the motor speed or the position of the eccentric weight, the vibration force and frequency of the vibration motor can be adjusted to suit different testing requirements, simulating real-world vibration conditions for product testing and performance evaluation.

[0127] The controller module uses an STM32F103 processor and controls the vibration motor's frequency by varying the duty cycle of the PWM signal. The selected vibration motor parameters are a speed of 0-10kHz and a motor excitation force of 0.2kN. The motor's rated DC voltage is 24V and its power is 60W. The vibration control module has two control modes: manual and automatic. In manual control, the vibration frequency is set using a knob on the panel, and the digital display displays the frequency in real time. In automatic control, the host computer transmits the vibration frequency signal to the controller submodule via serial communication, thereby controlling the vibration motor's frequency.

[0128] Furthermore, the swinging mechanism of the vibrating platform is achieved by using a swing motor that, unlike traditional motors, can periodically reciprocate around a specific center position, providing a unique motion pattern. The swing motor can directly drive the load to achieve reciprocating deflection, while utilizing a rotary motor and an attached eccentric mechanical conversion device to achieve air chamber tilt and swing. Key technical specifications for the swing motor include: a swing frequency of 0.02Hz to 5Hz, a swing angle of ±35°, a load air tank, and a control voltage of ≤24V.

[0129] The condensation blockage described above is described in detail as follows: Condensation occurs when the water vapor content in the air reaches saturation. As the ambient temperature continues to drop, the supersaturated water vapor in the air condenses and forms water droplets. When the water vapor content in the air remains constant, the humidity gradually increases as the ambient temperature drops. When the temperature drops to a certain level, the air reaches saturation, with a relative humidity of 100%. If the ambient temperature continues to drop, the supersaturated water vapor in the air begins to condense and form water (water droplets). The condensation temperature is known in engineering as the "dew point." The condensation generator consists of a 2x3 array of water-filled droppers, located on the upper cover of the air chamber and sealed to the cover. During the condensation test, simply squeeze the rubber hose of the dropper to smoothly squeeze water out. Controlling the force can form droplets of varying sizes, forming condensation on the splash-proof housing of the sensor. When the water droplets completely soak the waterproof and breathable membrane, they block the exchange of air inside and outside the sensor, causing condensation.

[0130] It should be noted that relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus comprising the element.

[0131] Although the present application has been described above with reference to specific embodiments, various modifications may be made thereto and components may be substituted with equivalents without departing from the scope of the present application. In particular, as long as there are no structural conflicts, the various features of the embodiments disclosed herein may be combined with each other in any manner, and the omission of an exhaustive description of these combinations in this specification is solely for the sake of space and resource conservation. Therefore, the present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions within the scope of the claims.

Claims

1. A gas sensor array comprehensive test system, characterized in that: It includes an air chamber (1), a fault trigger (2), a programmable gas injector (3), a vibration swing platform (4), a data communication module (5), a signal acquisition and conditioning module (6), and a host computer (7); The air chamber (1) is arranged on a vibrating and rocking platform (4), and the air chamber (1) is respectively connected to a fault trigger (2), a programmable gas injector (3), a data communication module (5), and a signal acquisition and conditioning module (6); the signal acquisition and conditioning module (6) is connected to the data communication module (5), and the data communication module (5) is connected to a host computer (7); The air chamber (1) comprises a box body (1-1), a sealed pressure-resistant cover (1-2) and a condensation dripping pipe (1-3) are installed on the top of the box body (1-1), and the condensation dripping pipe (1-3) extends into the box body (1-1), and a sensor array (1-4), a monitoring sensor (1-5), a humidifier (1-7), a heater (1-8), and a fan (1-9) are arranged in the box body (1-1); the sensor array (1-4) is respectively connected to a fault trigger (2), a data communication module (5), and a signal acquisition and conditioning module (6), and the monitoring sensor (1-5) is connected to the data communication module (5); The sensor array (1-4) is connected to a signal acquisition board (1-6), and the condensation dripping pipe (1-3) is arranged above the sensor array (1-4); A gas injection hole is provided on the side of the gas chamber (1) for connecting to a program-controlled gas injector (3); The programmable gas injector (3) is used to inject a certain concentration range of gas into the gas chamber; The fault trigger (2) is used to simulate the on-off sudden fault of the connection between the sensor functional components, the sensor sensitive resistor fault, the condensation dropper based on the condensation blockage fault simulation, and the program-controlled DC power supply based on the working voltage and heating voltage sudden fault simulation; The vibrating and rocking platform (4) is used to achieve the tilting, rocking and vibration actions of the air chamber (1).

2. A gas sensor array comprehensive test system according to claim 1, characterized in that: The number of the monitoring sensors (1-5) is five, including a temperature sensor, a humidity sensor, an air pressure sensor, a vibration sensor, and an inclination angle sensor. The sensor array (1-4) includes nine semiconductor gas sensors. A ceramic tube with a heating wire is placed inside the semiconductor sensor. The ceramic tube is coated with a sensitive material. When the heating wire of the ceramic tube with the heating wire is energized and heated, the temperature of the ceramic tube rises to a range of 200°C to 450°C.

3. A gas sensor array comprehensive test system according to claim 1, characterized in that: The fault trigger (2) simulates an on-off sudden fault of the connection between the functional components of the sensor, including connecting a program-controlled relay in series with the heating wire connection end and the signal lead end of the sensor array (1-4), and using the on and off of the program-controlled relay to simulate the connection of the sensor array (1-4) to be on or off or virtual on or virtual off; The fault trigger (2) simulates a sensor sensitive resistance fault, including connecting a programmable potentiometer in series to the signal lead end of the sensor array (1-4), and utilizing the resistance change of the programmable potentiometer to simulate a sudden fault such as cracking of the sensitive body, warping of the sensitive body, or shedding of the sensitive film of the semiconductor sensor in the sensor array (1-4).

4. A gas sensor array comprehensive test system according to claim 1, characterized in that: The programmable gas injector (3) comprises syringes of different volume specifications mounted on a linear slide of a stepping motor, and the gas injection volume and gas injection speed of the syringes are controlled by controlling the step length of the linear slide and the interval of gas injection action. The number of the syringes is 1 to 5, and the needles of the 1 to 5 syringes are connected to the gas injection holes of the gas chamber (1) through gas injection tubes. The programmable gas injector (3) uses 100% pure gas to generate gas with a lower concentration limit of 5ppb and an upper concentration limit of 8vol% to be injected into the gas chamber, and the gas injection action control time interval is adjustable in the range of 1s to 3h.

5. A gas sensor array comprehensive test system according to claim 1, characterized in that: The vibrating and rocking platform (4) utilizes a rotating motor and an additional eccentric wheel mechanical conversion device installed on a bracket to achieve the tilting and rocking movement of the air chamber (1). The vibrating and rocking platform (4) utilizes a vibrating motor installed on a bracket to achieve the vibrating movement of the air chamber (1).

6. A gas sensor array comprehensive test system according to claim 1, characterized in that: The host computer (7) receives signals from the data communication module (5), receives collected temperature, humidity, air pressure, vibration, swing, and gas concentration information data, collects output signals from the sensor array (1-4), extracts characteristic information, and performs data processing. The signal acquisition board (1-6) realizes the connection between the sensor array (1-4) and the signal acquisition and conditioning module (6).

7. A gas sensor array comprehensive test method, implemented by a gas sensor array comprehensive test system according to any one of claims 1 to 6, characterized in that: Before testing, semiconductor sensors are installed on the signal acquisition board to form a sensor array. Power is then turned on to allow the sensors to reach a stable state. The working status of the fan used to accelerate gas diffusion, the monitoring sensor used to monitor environmental information, the heating coil used to change the ambient temperature, the humidifier used to change the ambient humidity, and the condensation dropper are tested. Once all tests are normal, a sealed pressure-resistant cover is installed on the gas chamber. Then the blower is modulated into working state, the standard heating voltage and standard operating voltage of the semiconductor sensor are adjusted, and after the programmable gas injector injects gas from the hole on the left side of the gas chamber, the sensor array outputs the signal to the signal acquisition and conditioning module for signal acquisition; during the test process, the gas concentration control, injection rate control and injection interval control of the gas chamber are realized through the programmable gas injector.

8. A comprehensive test method for a gas sensor array according to claim 7, characterized in that: The method for signal acquisition and sensitivity adjustment by the signal acquisition and conditioning module includes the following steps: S1. Set up the sensor signal adjustment circuit of the signal acquisition and conditioning module, including the sensitive resistor Rs and the programmable potentiometer , adjustable resistor R L , sampling resistor R0, the sampling resistor R0, the adjustable resistor R L , programmable potentiometer , sensitive resistor Serial connection, the programmable potentiometer The high potential end of the sensitive resistor Rs connected in series in the output circuit of the semiconductor sensor; The sensor signal adjustment circuit adopts the voltage division method, in which a program-controlled power supply is used to provide the working voltage for the semiconductor sensor. Under normal conditions, the working voltage of the semiconductor sensor is 5V±0.05V, using DC mode. To test the circuit voltage, the load resistor output voltage is proportional to the sensor sensitive resistance. The relationship is: ； When the sensitive resistor When the load resistance decreases, the output voltage Increase, by collecting the load resistance voltage Reflects the sensor's response to gas and is used for gas-sensitive characteristics testing and data analysis; The resistance adjustment range of the programmable potentiometer is 0 to 501KΩ; S2. Power on the semiconductor sensor and determine the zero output. S3. Place the semiconductor sensor in the gas concentration to be measured. When the semiconductor sensor outputs a steady-state value, adjust the programmable potentiometer. Output, as the potentiometer output resistance increases, the sensor sensitivity decreases. When the potentiometer is adjusted to a certain resistance, the sensitivity of the sensor under the measured gas concentration is obtained. The sensor sensitivity S is defined as the sensor output voltage under the action of unit methane volume fraction C. The change is expressed as: 。 9. A comprehensive test method for a gas sensor array according to claim 8, characterized in that: In step S1, the semiconductor sensor heating voltage V h The setting method is: A programmable power supply is used to provide heating voltage for the semiconductor sensor heating wire; Under normal conditions, the semiconductor sensor heating wire operates at 5V±0.05V, and the semiconductor sensor detects single methane gas; Under normal conditions, the semiconductor sensor heating wire operates at 5V±0.05V, and the semiconductor sensor detects single hydrogen sulfide gas; Under the condition of known methane and hydrogen sulfide mixed gas, the programmable DC power supply is used to adjust the semiconductor sensor heating wire to work from 5V to 4V. At this time, the semiconductor sensor will show that it is insensitive to methane and only sensitive to hydrogen sulfide gas, thereby realizing the detection of hydrogen sulfide gas.

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