DIY - Interactive Decor (STEM)

Hello there I'm happy that this project caught your interest. So last Christmas I turned a normal snowman into an interactive snowman using an Arduino and an Ultrasonic sensor. Here I used a snowman because it was already made of cardboard and the inside was hollow. u can use any character, for any occasion with the same mechanism.

How does this work?

It's pretty simple. If someone passes in front of the snowman, the sensor will sense it, and the arm of the snowman will move.

• Arduino UNO
• Ultrasonic sensor
• Micro Servo
• Bread Board
• Jumper wire
• LED
• Threads
• Arduino IDE & Cable
• Character model

This is the circuit I made with Tinkercad Circuits.

Here you can see that the trigger pin and Echo pin of the sensor are connected to D8 and D9.

The signal pin of the servo is connected to D11.

Others are voltage and ground connections.

Make sure that the Arduino Uno will get a sufficient voltage supply otherwise the servo won't work properly.

The code is really simple in this project even though few think it is complex.

Inside the code, you can change the value of the sensing distance and servo angles.

Make sure to check the type of board and proper port number during the time of upload.

This is the basic idea.

Extend the length of the arm to inside the cardboard. attach threads at the end of the arms.

Fix the servo below the middle position and increase the shaft length for a better angle. Then attach the other end of the thread to the shaft. try to get the proper position and angles before fixing it.

Here I have attached the ultrasonic sensor on the head of the snowman and decreased the sensing range so it won't annoy anyone. I have also additionally added some LEDs and a buzzer to make it more attractive.

This project can be implemented on any character, the only limit is your imagination.