Home‎ > ‎

"Experiments" with the MQ-3 Alcohol Sensor

UNDER CONSTRUCTION

Introduction

The MQ-3 Alcohol Sensor is one of a series of easy to use gas sensors that can be easily connected to an Arduino.  This sensor can be used to measure the blood alcohol content in a person by measuring the amount of alcohol is on their breath.

After work one Friday afternoon I set up the following circuit and test software.  The setup was a lot easier than I thought.

Hardware

The arduino test code

unsigned int val = 0;
unsigned char PIN = 0;
void setup() {
    Serial.begin(9600);
    pinMode(PIN,INPUT);
    }
void loop() {
    val = analogRead(PIN);
    Serial.println(val);
    delay(500);
    }

The "Experiment"

  1. Take test measurement before drinking
  2. Drink 1 shot of alcohol
  3. Wait 10 minutes without drinking
  4. Record test measurement
  5. Repeat steps 2-4 

The data

I will add here the results of the test data:
  1. Data on the warm up period when the sensor first turns on (this is why I wait for 30 seconds in my LPG Gas Sensor code before taking measurements)
  2. Data regarding the alcohol recorded on the breath of two test subjects.

Wiring diagram and schematic

Comments