Difference between revisions of "Matrix - MQ-3 Gas Sensor"

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[[File:MQ-2 Gas Sensor_1.jpg|thumb|MQ-3 Alcohol sensor]]
 
[[File:MQ-2 Gas Sensor_1.jpg|thumb|MQ-3 Alcohol sensor]]
 
* The Matrix-MQ_3_Gas_Sensor module uses the MQ-3 gas sensor which is sensitive to alcoholic vapors and thus can be used to detect the density of an alcoholic vapor.
 
* The Matrix-MQ_3_Gas_Sensor module uses the MQ-3 gas sensor which is sensitive to alcoholic vapors and thus can be used to detect the density of an alcoholic vapor.
−
* The output voltage of the module is non-linear but close to linear to the density of alcoholic vapors.
+
* The output voltage of the module is non-linear but close to linear to the concentration of alcoholic vapors.
 
* In order to increase its accuracy before use it to detect a gas warm it up for one minute as long as it is not overheated.
 
* In order to increase its accuracy before use it to detect a gas warm it up for one minute as long as it is not overheated.
  
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|}
 
|}
  
−
==工作原理==
+
==Basic Device Operation==
−
Matrix-MQ_3_Gas_Sensor模块的主要器件是一个具有快速响应和恢复特性的MQ-3气体传感器，传感器所使用的气敏材料是在清洁空气中电导率较低的二氧化锡(SnO2)，当传感器所处环境中存在酒精蒸汽时，传感器的电导率随空气中酒精蒸汽的浓度增加而增大，传感器将电导率的变化转换为与酒精蒸汽浓度相对应的模拟信号输出，灵敏度可以通过电位计进行调节。
+
The Matrix-MQ_3_Gas_Sensor module employs a responsive MQ-3 gas sensor. Its gas sensitive material is SnO2. When the alcohol concentration in the air increases the sensor conductivity will increase accordingly and the module will convert the change of conductivity to analog signals. The sensitivity can be adjusted by the potentiometer.
  
 
==Applications==
 
==Applications==
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|}
 
|}
  
−
==编译运行测试程序==
+
==Compile & Run Test Program==
−
启动开发板并运行Debian系统，进入系统后克隆Matrix代码仓库：
+
Boot your ARM board with Debian and copy the matrix code:
 
<syntaxhighlight lang="bash">
 
<syntaxhighlight lang="bash">
 
$ apt-get update && apt-get install git
 
$ apt-get update && apt-get install git
 
$ git clone https://github.com/friendlyarm/matrix.git
 
$ git clone https://github.com/friendlyarm/matrix.git
 
</syntaxhighlight>
 
</syntaxhighlight>
−
克隆完成后会得到一个名为matrix的目录。
+
If your cloning is done successfully a "matrix" directory will be generated.
  
−
编译并安装Matrix：
+
Compile and install Matrix:
 
<syntaxhighlight lang="bash">
 
<syntaxhighlight lang="bash">
 
$ cd matrix
 
$ cd matrix
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</syntaxhighlight>
 
</syntaxhighlight>
  
−
运行测试程序：
+
Run test program:
 
<syntaxhighlight lang="bash">
 
<syntaxhighlight lang="bash">
 
$ matrix-adc
 
$ matrix-adc
 
</syntaxhighlight>
 
</syntaxhighlight>
−
注意：此模块并不支持热插拔，启动系统前需要确保硬件连接正确。<br>
+
Note: this module is not plug and play therefore before running the module please make sure it is connected to an ARM board.<br>
−
运行效果如下：<br>
+
Here is what you should observe:<br>
 
<syntaxhighlight lang="bash">
 
<syntaxhighlight lang="bash">
 
The channel0 value is 2460
 
The channel0 value is 2460
 
</syntaxhighlight>
 
</syntaxhighlight>
−
当空气中酒精浓度较高时会检测到事件，酒精的浓度越大，读取到的值越大。
+
When the concentration of alcoholic vapors reaches a threshold value an event will be triggered. As the concentration increases the value will increase.
  
−
==代码说明==
+
==Code Sample==
−
所有的开发板都共用一套Matrix代码，本模块的测试示例代码为matrix-analog_to_digital_converter，内容如下:
+
This Matrix code sample can work with all the ARM boards mentioned in this module's wiki. The name of this code sample is "matrix-analog_to_digital_converter". Here is its source code:
 
<syntaxhighlight lang="c">
 
<syntaxhighlight lang="c">
 
int main(int argc, char ** argv)
 
int main(int argc, char ** argv)
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}
 
}
 
</syntaxhighlight>
 
</syntaxhighlight>
−
API说明参考维基：[[Matrix API reference manual/zh|Matrix API reference manual]] <br>
+
For more details about this APIs called in this code sample refer to [[Matrix API reference manual]] <br>
  
−
==相关资料==
+
==Resources==
 +
 
 +
==Update Log==
 +
===June-21-2016===
 +
* Created English wiki

Latest revision as of 16:05, 21 June 2016

查看中文

1 Introduction

MQ-3 Alcohol sensor
  • The Matrix-MQ_3_Gas_Sensor module uses the MQ-3 gas sensor which is sensitive to alcoholic vapors and thus can be used to detect the density of an alcoholic vapor.
  • The output voltage of the module is non-linear but close to linear to the concentration of alcoholic vapors.
  • In order to increase its accuracy before use it to detect a gas warm it up for one minute as long as it is not overheated.

2 Features

  • Standard 3 PIN header
  • PCB dimension(mm): 24 x 32

MQ-3 Gas Sensor.PCB

  • Pin Description:
Pin Description
S GPIO
V Supply Voltage 5V
G Ground

3 Basic Device Operation

The Matrix-MQ_3_Gas_Sensor module employs a responsive MQ-3 gas sensor. Its gas sensitive material is SnO2. When the alcohol concentration in the air increases the sensor conductivity will increase accordingly and the module will convert the change of conductivity to analog signals. The sensitivity can be adjusted by the potentiometer.

4 Applications

The Matrix-MQ_3_Gas_Sensor module outputs analog signals which can be converted to digital signals through an ADC converter e.g. the Matrix-Analog_to_Digital_Converter module.
For more details about the Matrix-Analog_to_Digital_Converter module refer to wiki: Matrix_-_Analog_to_Digital_Converter.

4.1 Connect to NanoPi M1

Refer to the following connection diagram to connect the module to the NanoPi M1:
Matrix-MQ_3_Gas_Sensor_nanopi_m1

Connection Details:

Matrix-MQ_3_Gas_Sensor
GND NanoPi M1 Pin9
5V NanoPi M1 Pin2
S Matrix-Analog_to_Digital_Converter A0

4.2 Connect to NanoPi 2

Refer to the following connection diagram to connect the module to the NanoPi 2:
Matrix-MQ_3_Gas_Sensor_nanopi_2

Connection Details:

Matrix-MQ_3_Gas_Sensor
GND NanoPi 2 Pin9
5V NanoPi 2 Pin2
S Matrix-Analog_to_Digital_Converter A0

4.3 Connect to NanoPi M2 / NanoPi 2 Fire

Refer to the following connection diagram to connect the module to the NanoPi M2/ NanoPi 2 Fire:
Matrix-MQ_3_Gas_Sensor_nanopi_m2

Connection Details:

Matrix-MQ_3_Gas_Sensor
GND NanoPi M2 Pin9
5V NanoPi M2 Pin2
S Matrix-Analog_to_Digital_Converter A0

4.4 Connect to NanoPC-T2

Refer to the following connection diagram to connect the module to the NanoPC-T2:
Matrix-MQ_3_Gas_Sensor_NanoPC-T2

Connection Details:

Matrix-Potentiometer
GND NanoPC-T2 USB Host GND
5V NanoPC-T2 USB Host 5V
S Matrix-Analog_to_Digital_Converter A0

5 Compile & Run Test Program

Boot your ARM board with Debian and copy the matrix code: 

$ apt-get update && apt-get install git
$ git clone https://github.com/friendlyarm/matrix.git

If your cloning is done successfully a "matrix" directory will be generated.

Compile and install Matrix: 

$ cd matrix
$ make && make install

Run test program: 

$ matrix-adc

Note: this module is not plug and play therefore before running the module please make sure it is connected to an ARM board.
Here is what you should observe:

The channel0 value is 2460

When the concentration of alcoholic vapors reaches a threshold value an event will be triggered. As the concentration increases the value will increase.

6 Code Sample

This Matrix code sample can work with all the ARM boards mentioned in this module's wiki. The name of this code sample is "matrix-analog_to_digital_converter". Here is its source code: 

int main(int argc, char ** argv)
{
    int i = 0;
    int value = 0;
    int channel = 0;
 
    if (boardInit() < 0) {
        printf("Fail to init board\n");
        return -1;
    }
 
    if (argc == 2)
        channel = atoi(argv[1]);
    system("modprobe "DRIVER_MODULE);
    signal(SIGINT, intHandler);
    for (i=0; i<ADC_READ_TIMES; i++) {
        if (pcf8591Read(channel, &value) != -1) {
            printf("The channel%d value is %d\n", channel, value);
        } else {
            printf("Fail to get channel%d value\n", channel);
        }
    }
    system("rmmod "DRIVER_MODULE);
 
    return 0;
}

For more details about this APIs called in this code sample refer to Matrix API reference manual

7 Resources

8 Update Log

8.1 June-21-2016

  • Created English wiki
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