This Project describes a design of effective alarm system that can monitor a vehicle accident. This project is designed to inform about an accident that is occurred to a vehicle to the family members of the traveling persons and traffic police and ambulance. This project uses a piezo-electric sensor which can detect the abrupt vibration when an accident is occurred. This sends a signal to microcontroller. A GSM modem is interfaced to the MCU. The GSM modem sends an SMS to the predefined mobile number and informs about this accident along with its location using a GPS modem which is also interfaced with the microcontroller.
The project is built around the AT89S52 micro controller from Atmel. This micro controller provides all the functionality of the SMS alert system.The uniqueness of this project is, not only alerting the neighbours by its siren, but also it sends a caution SMS to four mobile numbers. This numbers can be changed at any time by the user using a 3X4 key pad. These numbers are stored in EEPROM.
This project uses regulated 5V, 750mA power supply. 7805 three terminal voltage regulator is used for voltage regulation. Bridge type full wave rectifier is used to rectify the ac output of secondary of 230/12V step down transformer.