My little sister kept saying she’s taller than my action figures, and I wanted to check for real, so I built my Height Measuring Device with my Arduino Uno—my first coding project! I used a sensor from my Moonpreneur kit to measure stuff and see the numbers on my laptop. It’s so cool being a height detective!

I grabbed my Embedded Learner Uno v2 box and wired the ultrasonic sensor—VCC to 5V, GND to GND, TRIG to pin 2, and ECHO to pin 3 with jumper wires. In Arduino IDE, I wrote void setup() with pinMode(2, OUTPUT) for TRIG and pinMode(3, INPUT) for ECHO, plus Serial.begin(9600) to show results. In void loop(), I ping the sensor—digitalWrite(2, HIGH), delayMicroseconds(10), duration = pulseIn(3, HIGH)—and calculate distance with float height = duration * 0.034 / 2. I subtract it from a fixed point (like 100 cm above) to get the object’s height, then Serial.println(height) shows it in centimeters. The numbers were off at first, but I adjusted the math, and now I cheer when I measure my sister’s toys right!

I’m pumped to make it better next time! Maybe I’ll add an LCD to show the height, or a beep for super tall stuff. I could even measure my sister’s height for real! I really enjoy coding this with my Arduino, and I can’t wait to test it on all my figures with my friends!