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Electronics

2026 Sole designer
KiCadPython (generated schematic)STM32G431BLDC control
01 / Sized from the aircraft, not a catalogue

Sized from the aircraft, not a catalogue

The rating comes straight out of Hugin's own propulsion study: the climb case draws 53 A, so the board is built for 80 A continuous with 110 A of burst headroom on a 6S pack. Cruise only asks for about 5 A — the hard part is the three minutes of climb, and that is what the design is dimensioned around.

02 / Built for the case nobody publishes

Built for the case nobody publishes

Hugin's controller lives in a sealed fuselage bay, the worst possible thermal case. A survey of eight commercial 80 A controllers found that not one of them publishes how much current you can actually draw at a given temperature and airflow. This one is rated with its cooling condition stated — which is the thing the market was missing.

Figure 1. The power bridge — twelve transistors, three phases, one shunt.
03 / Twelve transistors, one honest measurement

Twelve transistors, one honest measurement

Three half-bridges switch the motor's phases, each built from two 60 V, 2.8 milliohm transistors in parallel — twelve of them sharing the battery current. Every amp that flows is measured by a single four-terminal shunt in the return path, which is also what the over-current protection watches.

Figure 2. Control and sensing — the processor, the back-EMF network that finds the rotor, and the hardware trip.
04 / Protection that doesn't wait for software

Protection that doesn't wait for software

An over-current fault trips in hardware: shunt, amplifier, comparator, straight into the motor timer's emergency shutdown at a 150 A threshold — no firmware loop anywhere in that path. Around it sit a transient clamp on the battery lead, temperature and voltage sensing, and pull-downs holding all twelve transistors off while the processor is still booting.

Figure 3. The gate-drive stage — generated, not drawn.
05 / Written as code, then checked by machine

Written as code, then checked by machine

The whole 160-part schematic is generated by a Python script and never drawn by hand, so a design change is a code change. Separate scripts re-verify all 28 processor pin assignments against the chip's datasheet — 28 of 28 pass. That discipline caught a review finding that all 22 Schottky diodes were fitted backwards, a fault the standard electrical check had happily passed.