International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395 -0056 Volume: 04 Issue: 04 | Apr -2017 www.irjet.net p-ISSN: 2395-0072 © 2017, IRJET | Impact Factor value: 5.181 | ISO 9001:2008 Certified Journal | Page 979 Alcohol Detection based Engine Locking System using MQ-3 Sensor Priyanka Sahu 1 , Sakshi Dixit 1 , Shruti Mishra 1 , Smriti Srivastava 1 1 B.tech students, Department of Electronics and Communication, IMS Engineering College, Ghaziabad-201009, Uttar Pradesh ---------------------------------------------------------------------***--------------------------------------------------------------------- Abstract - This paper describes the procedure of making driving safer than before which is achieved by using ATmega8 microcontroller and MQ-3 alcohol sensor. We have taken the driver’s conditions in real time environment and we intend to detect the alcohol using alcohol sensor connected to microcontroller such that when the level of alcohol crosses a permissible limit, the vehicle engine system turns off and the GPS module captures the present location of the vehicle which is sent to preregistered phone numbers using GSM module. Key Words:-Atmega8, MQ-3Sensor, GSM, GPS. 1.INTRODUCTION India had earned distinction in having more number of casualties due to road accidents around the world. Road safety is appearing as a big social concern around the world especially in India. Drinking and driving is a serious issue which probably would emerge as one of the most significant problems in the near future. The system proposed by us focus at minimizing number of road accidents in the near future because of drunk driving. The system detects the alcohol level present in the air inside the vehicle. At low level it sends an SMS to the preregistered contacts while at high level it locks the engine immediately and at the same time sends SMS along with the location to three pre-selected contacts. Hence the system will reduce the number of road accidents and casualties due to drunk driving in future. 2. HARDWARE MODULES The entire system adopted the ATmega8 Microcontroller, in the hardware as shown in figure-1, the core functions modules are ATmega8, Alcohol Sensor module(MQ-3),GPS Module, GSM Module, 16x2 LCD Display and DC Motor. Fig-1: Block diagram Atmega8: The ATmega8 microcontroller (a 28 pin IC) serves as the central unit of the system. All the components are interfaced to the microcontroller and programmed as per their purpose to operate in synchronization. Alcohol Sensor: It is used to detect alcohol. The analog output of which is applied to the ADC pin of ATmega8 microcontroller. GSM900: It sends an SMS to the contacts of the driver about the location of the vehicle. It is very beneficial and essential in emergency situations. GPS: It is used to locate the vehicle and the location is sent via SMS to pre-selected contacts of the driver through GSM900. LCD: If alcohol is sensed, it displays the message indicating Dz(igh Leveldz or DzLow Leveldz. DC Motor: It is used as an imitation for indicating the engine locking facility whenever alcohol is sensed.