Laser Security System (send message to Telegram)

Laser Security System with Telegram Notification

Introduction

This report describes a security system designed to detect interruptions in a laser beam path and send notification messages via Telegram. The system utilizes an Arduino-compatible NodeMCU microcontroller, a photodiode, a laser diode, and a Wi-Fi connection.

System Components

• NodeMCU: The microcontroller unit (MCU) that processes sensor data and controls the system’s functionality.
• Photodiode: A light sensor that detects the presence of the laser beam.
• Laser Diode: Emits a focused beam of light towards the photodiode.
• Wi-Fi Module: Enables the NodeMCU to connect to a Wi-Fi network and send messages to Telegram.
• LEDs:
  • Wi-Fi Connect LED: Indicates connection status to the Wi-Fi hotspot.
  • Laser Break Found LED: Illuminates upon detection of an interruption in the laser beam path.
  • Data Sent LED: Provides feedback on the success (fast blink) or failure (slow blink) of sending a Telegram notification.
• Buzzer: Generates an audible alarm upon laser beam interruption.

System Operation

1. Power Up: Upon powering the device, the Wi-Fi Connect LED begins blinking at a rate of 0.5 seconds, indicating it’s searching for a Wi-Fi network.
2. Wi-Fi Connection: The device connects to a Wi-Fi hotspot named “VIRUSR” with the password “12345678.” A constantly lit Wi-Fi Connect LED signifies a successful connection.
3. Normal Operation: Under normal circumstances, the laser beam continuously illuminates the photodiode. No alarms are triggered.
4. Laser Beam Interruption: When someone or something obstructs the laser beam path, the photodiode no longer receives light. This triggers the system:
   • Laser Break Found LED: Turns on, indicating a detected interruption.
   • Buzzer: Sounds an alarm.
   • Telegram Notification: The NodeMCU attempts to send a message to Telegram, including a timestamp.
     • Success: Data Sent LED blinks rapidly at 0.2 seconds, signifying successful message transmission.
     • Failure: Data Sent LED blinks slowly at 0.5 seconds, indicating a failed message transmission.

Report Summary

This report details a cost-effective and user-friendly laser security system. The system offers remote notification via Telegram, enabling users to be alerted of potential security breaches even when not physically present at the monitored location.

Additional Considerations

• The report can be further enhanced with a circuit diagram for better visualization of component connections.
• Include information on the specific NodeMCU programming language and libraries used to implement the system’s logic.
• Security improvements like password encryption for the Wi-Fi credentials can be explored.