Integrate, measure, and debug

Understand the idea

Debug from the outside inward: confirm the supply voltage under load, ground continuity, polarity, wiring, and component ratings before editing control code. A schematic and a measured voltage at the actual component help separate a power problem from a logic problem.

Bring a system up in stages. Test the sensor by itself, then the controller output, then the driver without the mechanism, and finally the complete assembly at low energy. This reduces the number of possible causes when something behaves unexpectedly.

Write down the symptom, the condition that triggers it, one hypothesis, and one test. Change only one thing per test. If current, temperature, motion, or sound becomes unsafe, disconnect power and inspect before continuing.

Worked example

If a rover resets when a motor starts, first measure the logic rail during startup. If it dips, isolate the power issue with a suitable supply and wiring before changing PID constants; software tuning cannot repair a brownout.

Try it at the bench

1. Make a one-page block diagram and a pin-to-pin wiring table for a small sensor-and-motor build.
2. Create a bring-up checklist with a current limit, first-power sequence, and stop conditions.
3. Add a short test log: expected result, measured result, and next hypothesis.

Check your understanding

Why change one variable per troubleshooting step?