Ultrasonic Theremin
A touchless musical instrument inspired by the classic Theremin — played entirely by moving your hand through the air, with no physical contact required.
Play the Theremin
Move your mouse/finger across the play area below. Distance from left = pitch. Click to toggle mute.
Servo Arc Dial
LED Bar Graph
Session Stats
How It Works
1. Ultrasonic Sensing: The HC-SR04 sensor continuously measures the distance of the player's hand using ultrasonic sound waves.
2. Pitch Mapping: As the hand moves closer, the pitch rises. As it moves further away, the pitch drops — creating a smooth, continuous glide of notes.
3. Servo Arc Display: A servo motor needle sweeps across an arc scale like a speedometer, visually tracking the pitch level in real time.
4. LED Bar Graph: Five LEDs rise and fall as a bar graph display alongside the arc dial, giving a visual representation of the current pitch level.
5. Mute Toggle: A button on the panel acts as a mute toggle — pressing it silences the instrument instantly and dims the display.
Components
Enclosure
Housed inside a cardboard enclosure with a styled front panel, arc scale print, and visible needle — designed to look like a retro instrument face.