Notes from the bench
Tutorials, troubleshooting, component choices and post-mortems — written from builds in the Lab rather than from theory.
Why My Robot Kept Turning Right
Four evenings spent replacing hardware to fix a software bug. A walk through the debugging path that should have been taken first, and the one measurement that would have ended it on night one.
Understanding PID Control for a Small Robot
PID explained through one concrete job — holding a heading on a two-wheel rover — with the tuning order that actually converges and the three failure modes you will hit first.
ESP32 + MPU6050: Getting Usable Yaw Data
Register setup, DLPF selection, sample rate, and the complementary filter — plus why yaw is the hardest of the three axes to get right without a magnetometer.
How to Use a Gyroscope for Robot Heading Control
What a gyroscope actually measures, why integrating it drifts, and how to combine it with a second sensor so your heading estimate stays honest over minutes rather than seconds.
Choosing a Motor Controller
A decision path through brushed, brushless and stepper drivers, with the current-rating trap that catches most first builds and why continuous rating matters more than peak.
Eleven Reflow Profiles, Measured
Thermocouple traces from eleven paste-and-board combinations, including the three that produce reliable joints on heavy ground pours and the two that never will.
Working on the same problem?
If one of these notes nearly solved it and then didn't, tell us where it fell over. That is usually the start of a project.