Drawer Security Alarm

• 

  Hardware / Cover Photo

• 

  Code snippet

• 

  The Blynk dashboard

Inspiration

You have probably experienced siblings invading your privacy, co-workers taking your post-it notes, or parents taking things from your desk and losing them. We wanted to make a device that could monitor and protect a storage area in a casual context.

Description

The Drawer Security Alarm detects when your drawer is opened and warns the intruder. It is built using Arduino and the NodeMCU's WiFi capabilities. It's main features include:

• A motion sensor to detect if the drawer is open
• LEDs and a buzzer to warn unwanted intruders
• A keypad to disable the alarm
• A mobile dashboard using Blynk which features real-time notifications to your phone

What we worked on

To start, Eli and Rohan both built the ping sensor and LED hardware / software to become comfortable with a creative project and help each other with any obstacles. Once we had the basic project working, we split to add additional functionalities. Rohan added the buzzer element, and Eli implemented the key pad.

Challenges we ran into

Pin Mapping: Figuring out how to include all the ping, buzzer, LED, and keypad functions with a limited number of pins, mixing up trig/echo pins, nodeMCU -> Arduino pin mapping

Code: How to use new functions [ tone() , Blynk.notify() ]

NodeMCU: Not enough pins on nodeMCU to use keypad initially, had to rewrite RX pin to be used as an output

Built With

• arduino
• nodemcu