Introduction: Hand Wash Reminder

About: 🧑‍💻Passionate software engineer at Siemens, dedicated to driving digitalization by day. 🧑‍🏭By night, I'm a maker exploring IoT, product design, electronics, CAD, and 3D printing, sharing my projects with the w…

The Hand Wash Reminder is a hand band which reminds you to wash your hands after every 20 minutes. It has three color modes , Red indicating hands to be washed,color fading mode(30sec) for rubbing the hands for 30 Seconds and Green for the washed hands.

Hand Wash Reminder is made using a Arduino Nano,a WS2812b LED and a home made Vibration Sensor. Whenever a person wants wash his/her hands they have to shake their hand with force so that vibration sensor detects the vibrations and triggers the reset of the Arduino board. As Arduino is reset the program comes to the initial values and starts. First the fading colors are lighten on the LED for 30 seconds which acts as a timer for rubbing our hands for 30 seconds, after fading mode Green color lights on the LED it stays for 20 minutes indicating that your hands are washed,after 20 minutes LED lights with Red color indicating that your hands are not washed. The Red color stays until you shake your hand and wash your Hands.


  • Arduino Nano(1)
  • WS2812B LED(1)
  • 3.7V/5V Battery(1)
  • ON/OFF Switch(1)
  • Single Stand Wire(1)
  • Watch Strap/Hand Band(1)

Step 1: Making a Vibration Sensor:

  • Take a single stand wire remove the coating.
  • Make a spring using the wire.
  • Also take a straight wire of length same as the spring that we made.

  • Solder the spring and wire as shown in image to RST and GND of the Arduino board.

  • Make sure that wire is inside the spring and not touching the spring.

  • Using plastic tape cover the pins which are under the spring so that spring does not comes in contact to them.

Step 2: Circuit Connections:

  • Make all the connections as shown in circuit diagram.

Step 3: Code:

  • Open the code in Arduino IDE make sure to install FastLED library in the Arduino IDE.
  • Connect the Arduino to PC,select the board type,select port and upload.
  • After the code is uploaded make sure everything is working.
  • Code Link:

Step 4: Assembling:

  • 3D print the given STL files: .

  • Make a strap using the clips and belt or you can use any other strap that you have.

  • Assemble everything with the help of glue.

Step 5: Note:

  • You can adjust the sensitivity of the band by adjusting the spring and the wire on the board.
  • Adjust the sensitivity such that it should not trigger during the normal work, it should only trigger when the hand is jerked with a force.

Arduino Contest 2020

Participated in the
Arduino Contest 2020