This document describes a vehicle accident and alcohol sensing system that locks the engine if the driver is drunk or if an accident occurs. The system uses an alcohol sensor to detect alcohol levels in the driver's breath and sends a signal to a microcontroller. If alcohol is detected while starting the engine, it will not start. If alcohol is detected after starting, the engine will lock. The system aims to prevent drunk driving accidents by automatically stopping vehicles that are being operated by intoxicated drivers.

1. SYNOPSIS
ON
Vehicle Accident and Alcohol Sensing Alert with Engine
Locking System
SUBMITTED BY SUBMITTED TO
PRABHAT MISHRA (11151105) DR. SHARAD SHARMA
HITESH KUMAR SINGH (11151111) HOD, ECE DEPARTMENT
DEPARTMENT OF ELECTRONICS & COMMUNICATION
ENGINEERING
MAHARISHI MARKANDESHWAR ENGINEERING COLLEGE,
MULLANA
MAHARISHI MARKANDESHWAR (Deemed to be University), MULLANA-
133207

2. ABSTRACT
The main purpose behind this project is “Drunk driving detection”. Now a days, many accidents
are happening because of the alcohol consumption of the driver or the person who is driving the
vehicle. Thus, Drunk driving is a major reason of accidents in almost all the countries in the world.
Alcohol Detector in Car project is designed for the safety of the people seating inside the car. This
project should be fitted / installed inside the vehicle. If any Accident occurs then engine goes off
and Alarm goes on. If there is no alcohol / no accident, then the Engine remains on and Alarm
remains off. Even, if the Alcohol is detected, the engine goes off Alarm starts beeping.

3. OVERVIEW
We usually come across drink and driving cases where drunk drivers crash their cars under the
influence of alcohol causing damage to property and life. So here we propose an innovative system
to eliminate such cases. Our proposed system would be constantly monitoring the driver breath by
placing it on the driver wheel or somewhere the drivers breath can be constantly monitored by it.
So if a driver is drunk and tries to drive the system detects alcohol presence in his/her breath and
locks the engine so that the vehicle fails to start. In another case if the driver is not drunk while he
starts the vehicle and engine is started but he/she drinks while driving the sensor still detects
alcohol in his breath and stops the engine so that the car would not accelerate any further and driver
can steer it to roadside. In this system we use an AVR family microcontroller interfaced with an
alcohol sensor along with an LCD screen and a dc motor to demonstrate the concept. So here the
alcohol sensor is used to monitor user breath and constantly sends signals to the microcontroller.
The microcontroller on encountering high alcohol signal from the alcohol sensor displays alcohol
detection note on LCD screen and also stops the dc motor to demonstrate as engine locking. The
system needs a push button to start the engine. If alcohol is detected at the time of starting the
engine the engine does not start at all. If alcohol is detected after engine starting, the system locks
the engine at that time.

4. BLOCK DIAGRAM
POWER SUPPLY

5. DESCRIPTION
The main unit of this project is an “Alcohol sensor”. If the person inside car has consumed alcohol,
then it is detected by the sensor. Sensor gives this signal to a comparator IC. The output of
comparator is connected to the microcontroller. Microcontroller is the heart of this project. It is
the CPU of the complete circuit. Microcontroller gives high pulse to the buzzer circuit and the
buzzer is turned on. At the same time a relay is turned off. Due to this the ignition of the car is
deactivated.
COMPONENTS REQUIRED (HARDWARE)
• Microcontroller AT89S52
• Alcohol sensor
• LM324 comparator
• Buzzer
• LED’s
• DC motor(ignition)
• Driver IC
• LCD(16x2)
• Accident sensor /switch
SOFTWARE REQUIRED
• Embedded C
• Keil microvision3
• Express PCB

6. APPLICATIONS
1) “Alcohol Detector project” can be used in the various vehicles for detecting whether the driver
has consumed alcohol or not.
2) This project can also be used in various companies or organization to detect alcohol
consumption of employees.
Advantages
1) “Alcohol Detection System in Cars” provides an automatic safety system for cars and
other vehicles as well.
2) Hardware requirement is less
3) Very simple to implement
Disadvantages
1) The sensor can detect every type of alcohol like deodorant, mouth freshener etc.
2) The project detects the alcohol only after certain level.

7. CONCLUSION
This vehicle accident and alcohol sensing alert with engine locking system project can sense if
the person is drunk or not which is the main cause of the accidents these days, thus making
minimal chances of accident happening. The project can further alert the people around the
vehicle if any accident has taken place, so that they can help the person seating in the vehicle.
Not only this, the project is very cost effective and very easy to implement in any type of vehical.
FUTURE SCOPE
1) We can implement GSM technology to inform the relatives or owners of the vehicle about the
alcohol consumption.
2) We can implement GPS technology to find out the location of the vehicle.