ElectroBOOM

Resistive Touch Sensor #electronic #experiment #technology

The video walks through building a basic resistive touch sensor using everyday materials—a pencil‑drawn graphite line on paper, a copper‑tape probe, and a low‑voltage source. By measuring the strip’s resistance, which sits around one kilohm and drops with shorter traces, the creator demonstrates how voltage applied across the line creates a predictable gradient. Key data points include applying roughly 11.5 volts across the graphite, which produces a voltage divider effect that can be read at any point along the strip. Moving the probe changes the measured voltage, effectively mapping finger position in one dimension. Insulating the contacts with tape and using a copper strip as the sensing tip allows the voltage to be monitored on an oscilloscope. A notable example shows the probe sliding over the strip while a finger presses down, producing a distinct voltage shift that pinpoints the finger’s location. The presenter suggests extending the concept to two dimensions and adding a transparent overlay to create a functional touch interface suitable for modern displays. The experiment underscores how simple resistive principles underpin today’s touchscreens, offering a low‑cost, educational platform for prototyping and understanding the physics behind touch input technology.