Interactive 3D Sound Antenna for Real-Time Sound Localization and Visualization

Overview

Locating small air leaks in bike inner tubes is challenging because hissing sounds are often too quiet to hear. Traditional methods take time and effort because finding air leaks requires removing the tube and submerging it in water. To solve this problem, a low-cost, real-time sound localization system called the 3D Sound Antenna was built. The system used four microphones arranged in a 3D configuration and a Teensy 4.1 microcontroller. Sound direction was calculated using Generalized Cross-Correlation with Phase Transform (GCC-PHAT), an advanced digital signal processing (DSP) algorithm that measures the time difference of arrival (TDOA) between microphones. Indoor tests used hand claps and finger snaps at distances from 0.5 m to 3 m, with 40 trials per distance. Hand claps were detected 100% of the time while finger snaps were detected 100% up to 2 m and dropped to 85% at 3 m. A sinusoidal relationship between the TDOA and sound direction was observed and the average angular resolution was 3°. The system detected hissing sounds from a punctured inner bike tube in 90% of trials (18 of 20). This reduced the time needed to locate leaks to under 20 seconds. Detection accuracy dropped to 5% (1 of 20) when the inner tube remained inside an outer tire because of attenuation and multipath effects, which affected GCC-PHAT calculations. An eyeball tracker for real-time visualization and a sound-controlled game, Mosquito Hunt, were also created to demonstrate the system’s capabilities. The 3D Sound Antenna was built for under $100 using recycled materials and provided educational value for exploring sound physics and DSP principles in a fun and interactive way. These results showed that advanced DSP algorithms could run on a low-cost microcontroller for real-time sound localization.

Competition history

• CSEF 2026 Electronics & Electromagnetics (Junior Division) · Entry J-10-14

Related projects

Closest projects by meaning, across every fair and year in the corpus.

Browse more like this

• All Physics and Astronomy projects
• CSEF Physics and Astronomy projects
• Every CSEF 2026 project