Instant access to electric light is a luxury that most of us take for granted, but in times of crisis, the power is often the first thing to go. So whether you’re worried about a natural disaster or the outbreak of war, a reliable source of light is a must-have in your emergency kit. Creator [bobricius] calls his is ArmaLamp the “Armageddon resistant night lamp”, and while we’re not eager to test that particular claim, it certainly looks robust enough to get you through some tough times.
The basic idea behind the ArmaLamp is to make a light source so simple that, outside of being physically destroyed, it can’t fail. That means deleting the mechanical power switch and designing the circuit so the LED light will kick on automatically in the dark. Rather than using a traditional rechargeable battery, the solar powered ArmaLamp stores its charge in a 10 farad supercapacitor that can be charged and depleted daily without having to worry about long-term degradation.
Charging the ArmaLamp with a simple solar cell is clearly out of the question as it would represent not just a single point of failure, but a particularly fragile one at that. Instead, [bobricius] is using an array of six BPW34 photodiodes that come in a hard plastic package. Combined with an efficient driver circuit that can run the LED even when the supercap is down to 0.3 V, leaving the ArmaLamp outside during the day should provide you with four hours of ultra-reliable light every night.
Continue reading “2022 Hackaday Prize: ArmaLamp Provides Light, No Matter What”