I was home with my oldest son on a Saturday. I decided to build a simple robot while he was napping. I had about 90 minutes.
With so little time to build and program the robot, I went straight to the recycle bin and found the shipping box of one of my Google Home Minis—perfect!
All I needed was my wife’s glue gun, a couple of servos, an Arduino Uno clone, and a couple of components.
I just wanted a simple system that would shake its arms when a presence was detected in front of it.
The sensing was done by an ultrasonic sensor module, HC-SR04. The arms were moved by two servos, and a piezzo let me push a beep when a presence was detected.
An LED flashed when the system was standing by.
The great thing about the HC-SR04 is that it really looks like eyes. Adding “eyes” to a box is possibly the fastest way to build a robot for a toddler—and it worked.
I wanted to add another layer of personality and I added a piezzo buzzer. I spent some time thinking about the melody the robot should be playing when a presence was detected. I settled for a descending do-sol-do but I want to spend more time thinking about sound in the context of HRI.