This document describes a drunk driving prevention system that aims to automatically lock a car's ignition if the driver has consumed alcohol. The system uses an alcohol sensor connected to a microcontroller to detect alcohol levels in the driver's breath. If alcohol is detected above a certain threshold, the microcontroller will activate a buzzer and shut off the car's ignition by engaging a relay circuit breaker system connected to the spark plug. The overall goal is to prevent drunk driving accidents by providing a technological solution to disable a vehicle if the driver has consumed too much alcohol, with the potential to one day integrate this directly into vehicle ignition systems for improved road safety.

1. Drunk Driving Prevention System
Under the Guidance of Prof. Jagdish Kumar & Dr. Mohd Alam
Presented by
Prachi Singla 17104028
Pratyush Kumar 17104049
Rayvin Thingnam 17104103
Juvraj 17104110
Manish Verma 17104113

2. Objective
• According to NCRB (National Crime Records Bureau), “Driving under
influence of alcohol contributed 1.7% of total accidents which
resulted in injuries to 6,675 persons and 2,972 deaths in the country
(India).”
• 8-9 deaths everyday due to alcohol induced driving!
Automatically lock the ignition system of the car in
case the driver has consumed alcohol.

3. Phase 1
The system makes use of a
comparator. The output from
alcohol sensor is fed to
comparator and according to
it comparator switches
ON/OFF the buzzer.
Comparator
Alcohol
Sensor
Reference
Voltage
Battery
Buzzer

4. Phase 1: Circuit Diagram
 Mq3 sensor
 Potentiometer
 Lm358 comparator
 Buzzer
 Resistors
 LED

5. Phase1: Working

6. Phase 2: Our Goal
 Substitute a car ignition system
to simulate the shut down of car
after sensing alcohol in breath of
the driver.
 For high sensitivity, fast response
and wide range detection, add a
microcontroller and for much
more information.

7. Major Components
 Regulated power supply.
 Microcontroller.
 DC motors with driver.
 Reset.
 Crystal Oscillator
 LED indicators.

8. Power Supply
Step down
transformer
(V-0-12 )
Bridge
Rectifier
Capacitive
Filter
Regulator
(7805)
230 v AC +5V DC
 Every embedded system requires dc voltage and that that will be 5v supply.
 Digital electronic devices need digital supply and we can get supply from
regulated power supply block.

9. Micro Controller
 PIC has four optional clock sources.
 RC oscillator (low cost).
 Programmable timers and on-chip ADC.
 Up to 12 independent interrupt sources.
 Powerful output pin control
 EPROM/OTP/ROM/Flash memory option.
 I/O port expansion capability.

10. Input: Alcohol 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

11. Output
PMDC Motor
 Smaller size
 Cost Efficient for Small Ratings
 No Field Circuit Copper Losses
 Good Efficiency
Piezo Buzzer
 High Reliability Electromagnetic Buzzers
 Applicable to Automobile Equipment
 Pin Type Terminal Construction
 Direct Mounting onto Circuit Boards

12. Circuit Diagram

13. Working

14. Real Time Application
Entire system will remain same as above prototype. Addition
of relay-circuit breaker system, in place of dc motor, to the
spark plug.

15. Limitations
• BAC different for different areas.
• Needs trial and testing to ensure safety.
• Limited knowledge of the ignition system.
• Abrupt stoppage of car can cause accidents.

16. Future Scope
• GSM to Alert Friends and Family.
• GPRS Technology to Track the Driver.
• More Research for Application in Vehicles.
• Safety Considerations
• Better Display Alert
• Better Sound Alert