Due to the global coronavirus outbreak, I want to make a doorbell that you don’t need to press any signals to the people inside that you are here and they must open the door . This thing can make you get the virus by touching other peoples doorbell when a diagnosed person touches it and spreads the virus to you.

Step 1: Tools

The tools that you will need to make this is

Two paper boxes

Arduino Leonardo board( any Arduino board would work)

Few wires

An ultrasonic sensor

A buzzer

Tape

Hot glue

Ruler

Duct tape

Utility knife

Mobile charger

Tape

Markers

Bread Board

Step 2: Code

Here is the code

Step 3: Connecting the Wires to the Board

Now in the step just connect the wires like the picture above, make sure that the ultrasonic sensor gets an extended wire and coil to connected parts with duct tape to make it stronger.

Step 4: The Outside

Now it’s time to work on the outside. First, get a small box, and measure the length of the ultrasonic sensor's length. Then cut a hole out of the box and put the sensor in it. For the box like the picture above, and make an arrow pointing down to the sensor. I made the arrow by sticking for long pieces of duct tape and use a marker to draw an arrow, then I use the hot glue to fill the arrow. Then I wait for the hot glue to dry and when it dries, I cut the arrow out and stick tape on it and then cut it out again to make it shiny. Then you take the other box which is the bigger one, you just make your eye do you know bored and your mobile charger and wires are fixed. Cut a little line on the box, so the buzzer can fit through, and put the buzzer on the box.

Step 5: Fixing It and Sticking It

At last, make the wires go through the gap between your door and your floor. Stick to boxes from two sides of your door. Add two pieces of cardboard and stick it on the wires on the door, making it safer.