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Courses From Blink to Bot — ESP32-S3 robotics with the Fre…

Lesson 6 · ~26 min · 🔒 Subscriber

Distance sensing — and why HC-SR04 lies

How time-of-flight ultrasonics work, why 5% of readings are bogus, and the filter that doesn't smooth out actual obstacles.


This lesson is in production. The arc below outlines what it will cover. Arc Pulse-width measurement using pulseIn; the speed of sound varies with temperature (real correction code); outlier rejection (median-of-three vs running average vs Kalman-lite); blind spots and what to do about them. Subscribed already? Your dashboard will show the lesson the moment it's published — no email required. Aiming for one new lesson per week; the full course will be complete within 8 weeks of launch.

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