Piezoelectric Sensing

This project implements a novel method to track ping pong balls bouncing on a flat surface by employing an array of four piezoelectric sensors mounted on a polycarbonate impact plate. High-speed signal processing is achieved using full-wave precision rectifiers and comparator circuits, which transform the analog signals from the piezos into digital logical signals. These signals are then rapidly processed by a Teensy V4.1 microcontroller, which estimates the ball’s impact position based on the order in which the sensors are triggered, rather than relying on inconsistent time delays. LEDs placed beneath each octant of the impact area visually indicate the detected position, with an additional LED reserved for impacts near the center.

Design considerations focused on selecting materials that balance low sound conduction with minimal vibration dampening, and the software was iteratively refined to reliably capture and interpret sensor data under high-speed conditions. The project not only demonstrates an effective tracking mechanism for dynamic impacts but also lays the groundwork for future enhancements, such as developing a dedicated PCB for improved reliability and further investigation into precise timing patterns for even more accurate tracking.

More details in report below.