Mike Bell's Raspberry Pi Pico Is Truly Steampunk — Running Entirely From a Scale Model Steam Engine
Why use batteries when you can turn to the best in Victorian engineering to run a microcontroller and display?
Mike Bell, chief technology officer at AI navigation specialist Mercuna Developments, has turned to an unusual power source for a Raspberry Pi Pico: a tiny but fully-functional steam engine.
"I got a steam engine! Here it is powering a dynamo connected to an LED light," Bell wrote of a video showing off the compact functional model of a traditional steam engine providing motive power for conversion to electricity. "When it's running at a good speed, around 3.3v. And somehow that little LED light is drawing 28mA!"
The next stage of experimenting with the toy was, of course, trying out other, more complex, electronics. With an estimated power output of around 90mW, a microcontroller was the obvious choice of load. "The setup is a [Raspberry Pi] Pico connected to a Pimoroni dot matrix display breakout. I've been tweaking this to minimise power consumption and believe it should run fine. The display will show the runtime of the system.
Sure enough, the little engine — a Wilesco D6 with M66 dynamo, designed as an educational model of the sort of coal-fired steam engines, which would have driven industrial revolution factory equipment — proved up to the task. "[It] ran for 11 minutes before I started to worry about the water level in the boiler. Voltage was around 3.8V — think I could draw a bit more power OK.
"I tried adding a small LCD display, with almost success. I guess the LCD backlight is cutting out in time for the voltage to recover without the system going down, and then that just repeats, hence the flickering."
It's not the first time we've seen electronics powered from an unusual source: Earlier this year a Palm IIIxe palmtop computer, built in 2000, was successfully driven from an alcohol-burning Stirling engine whose core concepts date back to Robert Stirling's work in 1816 — which was designed to provide an alternative to the then-ubiquitous steam engine, bringing us full circle back to the steam-driven Raspberry Pi Pico.
More details are available in Bell's Twitter thread.