The Dead Man Alarm using PIR Motion Sensor is a safety and security system designed to detect the absence of human movement for a predefined period and generate an emergency alert. The system uses a Passive Infrared (PIR) sensor to continuously monitor motion within a specific area. A PIC microcontroller processes the sensor signals and determines whether movement is detected. If no motion is sensed for the preset time, the controller assumes that the person may be unconscious, injured, or in need of assistance. When inactivity is detected, the PIC microcontroller activates a relay to operate a high-power siren and also turns on a buzzer to provide an audible warning. Simultaneously, an LCD display shows the alarm status, while an LED indicator provides a visual indication of system operation. A regulated power supply, crystal oscillator, and reset circuit ensure stable and reliable system performance. This project is suitable for monitoring elderly people, patients, security guards, factory workers, and individuals working alone. The system offers a simple, low-cost, and reliable solution for detecting prolonged inactivity and providing immediate alerts, thereby improving personal safety and enabling faster emergency response.        

Objectives:  

• To detect human movement using a PIR motion sensor.
• To identify prolonged inactivity of a person.
• To generate an alarm through a buzzer and siren when no motion is detected.
• To display the system status on an LCD display.
• To provide a low-cost and reliable personal safety monitoring system.
• To improve emergency response for elderly people, patients, and lone workers.

       

The major building blocks of this project are:  

1. Regulated power supply.
2. PIC Micro controller.
3. Passive Infra Red Sensor (PIR).
4. Relay
5. Buzzer.
6. LCD display.
7. Siren Sound.

            Regulated power supply:

                     

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