CN110658241A - Multiple gas detection device - Google Patents
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Abstract
The invention relates to a multi-gas detection device, which comprises a core processing unit, and a sensor data acquisition unit, an energy management unit, a man-machine interaction unit, an alarm unit and a communication interface unit which are connected with the core processing unit, wherein the sensor data acquisition unit comprises an electrochemical gas sensor, a double-gas sensor module and a temperature and humidity sensor module; the energy management unit mainly comprises a microcontroller, a DC-DC chip and an MOS (metal oxide semiconductor) tube and is responsible for power control, energy management and real-time timing of the whole device; the human-computer interaction unit comprises a liquid crystal display screen and a self-recovery key; the alarm unit mainly comprises a high-brightness LED lamp, a buzzer and a vibration motor; the communication unit is composed of an IrDA module. The invention has the advantages of low cost, convenient operation, low energy consumption and high intelligent degree.
Description
Technical Field
The invention belongs to the field of gas detection equipment, and particularly relates to a multi-gas detection device.
Background
At present, the contact combustion type gas sensor commonly used in the market has low measurement accuracy and poor stability and is easy to generate poisoning phenomenon. In order to meet the requirements of related qualification of national mine product safety, the gas sensor of the device can accurately and stably detect the gas concentration through chemical and physical methods to carry out electric signal conversion, and according to the characteristics of the property of a detection object and the detection environment, a plurality of types of high-precision sensors are selected to detect the minimum variable quantity of various gas concentrations, and the gas detection technology enters the miniaturization development process through high-precision and high-reliability device selection, better gas selectivity and lower power consumption. Compare contact combustion formula gas sensor in the past, the design of this device has guaranteed measuring range, resolution ratio and the error of demand side through the design of gathering of high accuracy, has avoided the production of poisoning phenomenon.
Disclosure of Invention
The invention aims to solve the problems and provide a multi-gas detection device which is low in cost and convenient to operate.
In order to achieve the purpose, the invention provides the following technical scheme:
a multi-gas detection device comprises a sensor data acquisition unit, a core processing unit, an energy management unit, a man-machine interaction unit, an alarm unit and a communication interface unit, wherein the sensor data acquisition unit comprises an electrochemical gas sensor, a double-gas sensor module and a temperature and humidity sensor module;
the energy management unit mainly comprises a microcontroller, a DC-DC chip and an MOS (metal oxide semiconductor) tube and is responsible for power control, energy management and real-time timing of the whole device;
the human-computer interaction unit comprises a liquid crystal display screen and a self-recovery key;
the alarm unit mainly comprises a high-brightness LED lamp, a buzzer and a vibration motor;
the communication unit is composed of an IrDA module;
the core processing unit is respectively connected with the sensor data acquisition unit, the energy management unit, the man-machine interaction unit, the alarm unit and the communication interface unit.
Furthermore, the gas sensor is used for converting corresponding gas information into an electric signal, and the signal conditioning circuit is responsible for conditioning the electric signal output by the sensor; the AD chip is used for converting the analog signal output by the signal conditioning circuit into a digital signal.
Furthermore, the core processing unit is connected with an AD chip communication interface to acquire a corresponding digital signal, the double-gas sensor module is in digital communication with the core processing unit through a UART interface, and the temperature and humidity sensor module is in digital communication with the core processing unit through an I2C interface.
Furthermore, the core processing unit mainly comprises an ARM processor of the STM32, controls the sensor data acquisition unit, and calculates, processes and stores acquired data.
Furthermore, the DC-DC chip is used for converting the battery voltage into a target voltage and supplying power to the whole circuit board; and the energy management unit controls the power supply of each module of the whole board through the MOSFET switch.
Preferably, the ARM processor is an STM32L462, and a storage module is arranged in the ARM processor.
Compared with the prior art, the invention has the beneficial effects that:
the invention can accurately and stably convert the detected gas concentration into an electric signal, selects the multi-type high-precision sensor to detect the minimum variable quantity of the gas concentration according to the characteristics of the property of the detection object and the detection environment, and leads the gas detection technology to enter the development process of miniaturization through the device type selection with high precision and high reliability, better gas selectivity and lower power consumption. Compared with the existing gas signal acquisition and processing mode, the device provided by the invention reduces heavy workload of ground personnel, is not limited by regions and environmental resources, realizes acquisition, processing and storage of gas concentration, and improves the efficiency of gas concentration acquisition and processing and the requirements of intellectualization and miniaturization. The gas sensor can meet the functions of preheating, measurement, data reading, storage, audible and visual alarm and the like of the gas sensor, and can realize the single-gas and multi-gas detection functions by changing the corresponding gas sensor.
Drawings
In order to more clearly illustrate the technical solution of the embodiment of the present invention, the drawings needed to be used in the description of the embodiment will be briefly introduced below, it is obvious that the drawings in the following description are only for more clearly illustrating the embodiment of the present invention or the technical solution in the prior art, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
FIG. 1 is a block diagram of the overall inspection apparatus of the present invention;
FIG. 2 is a circuit diagram of a charging system according to the present invention;
FIG. 3 is a flow chart of the operation of the detecting device of the present invention.
Detailed Description
In order to make the technical solutions of the present invention better understood and implemented by those skilled in the art, the present invention is further described with reference to the following specific examples, which are provided for illustration only and are not intended to limit the present invention.
As shown in FIG. 1, the gas detection device realizes gas detection, gas collection and gas data storage by adopting an ARM + AD and peripheral storage circuit scheme. The analog acquisition module determines the measurement range, response time, measurement precision and the like of the system. The current signal output by the three-level electrochemical gas sensor is converted into a voltage signal to be amplified and then connected to the ARM, and meanwhile, the anti-EMI characteristic of the device is improved by adding the RC filter circuit and the first-level follower at the output port. ARM mainly realizes the collection of gas concentration signal, humiture signal. The controller adopts a digital filtering algorithm in the aspect of software, and a program processes acquired data, so that the interference caused by address lines, power lines, signal lines, distributed capacitors, inductors and the like is reduced, and the data error in the ARM processor is further reduced. The algorithm reduces hardware cost, and improves the reliability, stability, convenience and flexibility of the device and the integrity of stored data.
Fig. 1 shows a schematic block diagram of the device, which mainly includes a sensor data acquisition unit, a core processing unit (including storage), an energy management unit (including microcontroller), a human-computer interaction unit, an alarm unit, and a communication interface unit; each unit part corresponds to each part of the system functional block diagram.
One, detection device constitution
1. Sensor data acquisition unit
The sensor data acquisition unit mainly comprises 3 electrochemical gas sensors, a double gas sensor module and a temperature and humidity sensor module. The electrochemical gas sensor data acquisition mainly comprises a gas sensor, a signal conditioning circuit and an AD chip, wherein the gas sensor is mainly responsible for converting corresponding gas information into an electric signal, and the signal conditioning circuit is responsible for conditioning the electric signal output by the sensor; the AD chip is mainly responsible for converting analog signals output by the signal conditioning circuit into digital signals, and the core processing unit acquires corresponding digital signals through the communication interface with the AD chip. The double-gas sensor module and the core processing unit are in digital communication through a UART interface, and a CPU (central processing unit) of the core processing unit only needs to read related data; the temperature and humidity sensor module is in digital communication with the core processing unit through an I2C interface, and the CPU of the core processing unit only needs to read related data.
2. Core processing unit (with storage)
The core processing unit is mainly composed of an ARM processor (STM32L462) of STM32, and is used for controlling the sensor data acquisition unit by loading a software program, calculating, processing and storing acquired data, and realizing communication and control of corresponding peripheral equipment.
The core processing unit is connected with the WIFI module through an SPI interface, is connected with the infrared interface, the alarm lamp, the micro motor, the buzzer and the button through GPIO, is connected with the debugging interface through ITAG, and is connected with the LCD through an LCD interface.
3. Energy management unit (with MCU)
The energy management unit mainly comprises a Microcontroller (MCU), a DC-DC chip and an MOS (metal oxide semiconductor) tube, and is responsible for power control of the whole board, energy management and real-time timing function. The current limiting device can limit the maximum power supply current of the battery, and the safety requirement is realized; the DC-DC chip converts the battery voltage into a target voltage and supplies power to the whole board; the power supply of each module of the whole board can be controlled by the energy management unit through the MOSFET switch.
4. Human-computer interaction unit
The man-machine interaction unit mainly comprises a liquid crystal display screen and 3 self-recovery keys. The liquid crystal display screen is used for displaying the current equipment state information and the related data information in real time; through 3 self-resuming buttons, operating personnel can operate handheld device.
5. Alarm unit
The alarm unit mainly comprises a high-brightness LED lamp, a buzzer and a vibration motor. The LED lamp is mainly used for optical signal alarm, the buzzer is mainly used for sound signal alarm, the vibration motor is mainly used for touch signal alarm, and when the equipment is in an alarm state, the core processing unit controls all parts to be in a corresponding alarm state.
6. Communication interface unit
The communication unit is mainly composed of an IrDA module, and the core processing unit imports and exports the equipment data through the IrDA module.
Second, charging system circuit
The charging system is divided into a charging mode and a communication mode, the handheld device can be charged in the charging mode, information interaction can be performed with the handheld device in the communication mode, and the two modes are switched by a switch, as shown in fig. 2. Has the following functions:
1) a protection module: EMC protection, which has functions of surge prevention, overcurrent protection and the like;
2) a charging module: managing a charging process of the battery;
3) a processor unit: USB protocol conversion, IrDA protocol conversion and other controls;
4) an infrared communication module: the function of importing and exporting data is realized;
5) an LED display module: a charge status indication.
Third, the working process of the detection device
Fig. 3 is a flow chart of contents of a liquid crystal display when the device starts to power on and performs man-machine interaction, which mainly includes a power on mode, a normal detection mode, a main menu mode, and the like. The realization functions mainly comprise:
starting up equipment;
shutting down the equipment;
measuring and displaying the running period;
fourthly, recognizing an alarm;
adjusting fresh air;
adjusting the gas calibration of a single measuring channel.
In order to ensure that the handheld device can be interfered in the actual operation and reduce the influence of the temperature characteristic of the sensor on the actual acquisition value, a data processing algorithm, a temperature compensation algorithm and production calibration software are built in the software.
1. And (3) a data processing algorithm:
1) and (3) limiting filtering method: pulse interference due to accidental factors is suppressed.
2) Median filtering: and filtering out accidental factor errors in the whole sampling period.
3) Arithmetic mean filtering: the signal is guaranteed to fluctuate around a certain range of values that can more accurately represent the actual environmental conditions over the current period of time.
4) Weighted sliding window average filtering algorithm: the adoption of the sliding window average filtering has good suppression effect on the periodic interference, the smoothness is high, but if the method is only adopted, the response of the system is poor, and therefore, the weighting algorithm is adopted, and the sensitivity is increased under the condition of ensuring the signal smoothness.
2. And (3) temperature compensation algorithm: except for the temperature compensation of the double gas sensors, the temperature compensation is needed when the other three gases are measured, and the algorithm needs to compensate the actual temperature curve into a straight line as much as possible, namely, the output cannot change along with the temperature change under a certain gas concentration. The algorithm acquires certain experimental data and then performs arithmetic fitting to obtain a temperature compensation coefficient, and then compensates a data result according to the corresponding temperature compensation coefficient, so that the measurement precision is improved.
3. Production of calibration software: because the electrochemical gas sensor product has the characteristics of difference and time drift, the handheld device needs to perform factory calibration tests (zero point return and temperature compensation parameters) before leaving the factory, in order to ensure the mass production calibration of the handheld device, the effectiveness, the time length and the operability of the production calibration need to be considered, and the device can execute another set of production calibration program during the production calibration.
The device provided by the invention reduces heavy workload of ground staff, is not limited by regions and environmental resources, realizes the collection, processing and storage of gas concentration, and improves the collection and processing efficiency of gas concentration and the requirements of intellectualization and miniaturization.
The details of the present invention not described in detail are prior art.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.
Claims (6)
1. The device for detecting multiple gases is characterized by comprising a sensor data acquisition unit, a core processing unit, an energy management unit, a man-machine interaction unit, an alarm unit and a communication interface unit, wherein the sensor data acquisition unit comprises an electrochemical gas sensor, a double-gas sensor module and a temperature and humidity sensor module;
the energy management unit mainly comprises a microcontroller, a DC-DC chip and an MOS (metal oxide semiconductor) tube and is responsible for power control, energy management and real-time timing of the whole device;
the human-computer interaction unit comprises a liquid crystal display screen and a self-recovery key;
the alarm unit mainly comprises a high-brightness LED lamp, a buzzer and a vibration motor;
the communication unit is composed of an IrDA module;
the core processing unit is respectively connected with the sensor data acquisition unit, the energy management unit, the man-machine interaction unit, the alarm unit and the communication interface unit.
2. The multiple gas detection device of claim 1, wherein the gas sensor is configured to convert the corresponding gas information into an electrical signal, and the signal conditioning circuit is configured to condition the electrical signal output by the sensor; the AD chip is used for converting the analog signal output by the signal conditioning circuit into a digital signal.
3. The multiple gas detection device of claim 1, wherein the core processing unit obtains corresponding digital signals through connection with an AD chip communication interface, the dual gas sensor module and the core processing unit are in digital communication through a UART interface, and the temperature and humidity sensor module and the core processing unit are in digital communication through an I2C interface.
4. The multiple gas detection apparatus of claim 1, wherein the core processing unit is mainly composed of an ARM processor of an STM32, and is used for controlling the sensor data acquisition unit and calculating, processing and storing acquired data.
5. The multiple gas detection apparatus of claim 4, wherein the ARM processor is a STM32L462 having a memory module therein.
6. The multiple gas detection device of any one of claims 1-5, wherein the DC-DC chip is configured to convert the battery voltage to a target voltage for powering the circuit board; and the energy management unit controls the power supply of each module of the whole board through the MOSFET switch.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111579719A (en) * | 2020-05-13 | 2020-08-25 | 广东电网有限责任公司广州供电局 | Wearable multiple gas detection device |
| CN111579727A (en) * | 2020-06-05 | 2020-08-25 | 广东电网有限责任公司广州供电局 | Multi-gas sensing detection device and method for power distribution room |
| CN113203775A (en) * | 2021-04-30 | 2021-08-03 | 国网上海市电力公司 | Many gas monitoring intelligence module |
| CN115452919A (en) * | 2022-09-21 | 2022-12-09 | 湖南爱益森科技有限公司 | Measurement system based on ceramic zirconia oxygen sensor in dispersed oxygen |
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