Driving under the influence of alcohol has affected and killed countless of people’s lives. If you drink and drive, not only do you possibly put yourself at risk, but your passengers and pedestrians, and other people, who were on the roads. Just think about that. Every thirty minutes someone’s life is cut short and families are devastated. So, here we implemented a prototype version Alcohol Detection system in order to control drunk and driving as much as we can. Please follow the link To Know about Different Types of Sensors with their Applications.
The Alcohol Detection system works on a simple principle, if a driver has been drinking, the alcohol breath analyser sensor will detect the level of alcohol in the driver’s breath and if it crosses a set threshold, an alert will come and the vehicle engine will stop immediately. This project is designed for the safety of the people seating inside/outside the vehicle.
Different types of Sensors
The most frequently used different types of sensors are classified based on the quantities such as Electric current or Potential or Magnetic or Radio sensors, Humidity sensor, Fluid velocity or Flow sensors, Pressure sensors, Thermal or Heat or Temperature sensors, Proximity sensors, Optical sensors, Position sensors, Chemical sensor, Environment sensor, Magnetic switch sensor , etc.
Functional Design of Automatic Engine Locking System through Alcohol Detection
The below block diagram illustrates the automatic vehicle engine locking system through an alcohol detection. The Microcontroller (AT89S52), alcohol detector (MQ-3), relay motor driver IC (ULN2003) are the major prerequisites for the system construction. The Alcohol detector sensor will be attached with our Microcontroller.
Block Diagram of Automatic engine Locking System with Alcohol Detection
The input for the Microcontroller is identified by the alcohol detector sensor through the breath of a human. In the next scenario the levels of alcohol measured by the sensor and compared with the set-in limits. If the set limit of consumption of alcohol is less than the alcohol consumed by the person, the system of activating relay is initiated which in turn activates the automatic lock on the vehicle, i.e. it stops the motor rotation if it is in running state or it is unable to start. The system will lock the Engine at the same time will automatically give a buzzer. By this, we can avoid accidents by checking the driving people on the roads. Software Program for the system developed in embedded C. ISP is used to dump the code into the Microcontroller.
Hardware Connectivity for Alcohol Detection System
For the proposed system we designed a circuit as shown below. In the circuitry, the connectivity issues have been shown with maximum reliability and negligible errors. This system works with 9v DC power supply.
Circuit Diagram of Automatic Engine Locking System through Alcohol Detection for Drunken Drivers
Microcontroller (AT89S52)
The AT89S52 Microcontroller is a low-power, high-performance CMOS 8-bit Microcontroller with 8K bytes of in-system programmable Flash memory. The device is manufactured BY Atmel, with the industry-standard 80C51 instruction set and Pin out. The on-chip Flash allows the program memory to be reprogrammed in-system or by a conventional non-volatile memory programmer. By combining a versatile 8-bit CPU with in-system programmable Flash on a monolithic chip, the Atmel AT89S52 is a powerful Microcontroller which provides a highly-flexible and cost-effective solution to many embedded control applications.
The AT89S52 Microcontroller provides the following standard features.
- 8K Bytes of In-System Programmable (ISP) Flash Memory
- Three-level Program Memory Lock
- 256 x 8-bit Internal RAM
- 32 Programmable I/O Lines
- Three 16-bit Timer/Counters and Watchdog Timer
- Full Duplex UART Serial Channel and Flexible ISP Programming (Byte and Page Mode)
- Low-power Idle and Power-down Modes
- Interrupt Recovery from Power-down Mode
MQ3- Alcohol Gas Sensor
MQ3- Alcohol Gas SensorMQ3- Alcohol Gas Sensor is a low-cost semiconductor sensor which, used to detect the presence of alcohol vapour gas at concentrations from 0.05 mg/L to 10 mg/L. It has high sensitivity to alcohol and has a good resistance to disturbances due to smoke, vapour and gasoline the sensitive material used for this sensor is SnO2, whose conductivity is lower in clean air. Its conductivity increases as the concentration of alcohol vapour gas increases. This module provides both digital and analog outputs.
This alcohol sensor is suitable for detecting alcohol concentration on your breath. It has a high sensitivity and fast response time. The sensor provides an analog resistive output based on alcohol concentration. The drive circuit is very simple, all it needs is a resistor. A simple interface could be a 0-3.3V ADC. The MQ3 alcohol sensor module can be easily interfaced with Microcontrollers, Arduino Boards, and Raspberry Pi etc.
Pin Out
- VCC – Input Power Supply
- DO – Digital Output
- AO – Analog Output
- GND – Supply Ground
Features of MQ3- Alcohol Gas Sensor
- Operating Voltage: 5V ± 0.1
- Concentration: 0.05 mg/L ~ 10 mg/L Alcohol
- Current Consumption: 150mA
- Output sensitivity adjustable
- Analog output 0V to 5V and Digital output 0V or 5V
- Low Cost and Fast Response
- Stable and Long Life
- Fair Sensitivity to Alcohol Gas
- Both Digital and Analog Outputs
- Operation Temperature: -10°C ~ 70°C
How an Alcohol Detector Works
To get a blood alcohol content (BAC) reading, the users simply have to blow into a straw attached to the equipment for a few seconds. From here, the machine utilises the vapours in your breath to calculate an estimation of the level of alcohol in a person’s system. This simple approach is due to the fact that alcohol is not digested by the body and is merely absorbed through different parts. These include the mouth, stomach and intestines. As a result, traces of the material can still be identified minutes after drinking, making it possible for the Breath Analyser to calculate an accurate number.
Blood Alcohol Content (BAC) limits
- The concentration of alcohol in blood: 0.05 grams per 100 millilitres (all drivers), professional drivers: 0.02 grams per 100 millilitres.
- Breath alcohol content: 0.24 milligrams per 1000 millilitres (all drivers), professional drivers: 0.10 milligrams per 1000 millilitres.
Applications of Automatic Engine Locking System through Alcohol Detection
Drunk Driving is one of the biggest threats to Road Safety. Applications of Automatic Engine Locking System through Alcohol Detection can be used anywhere to reduce the probability of road accidents.
- “Automatic Engine Locking System through Alcohol Detection project” can be used in various vehicles for detecting whether the driver has consumed alcohol or not.
- This can also be used in various companies, organisations, mines to detect alcohol consumption of employees.
