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4 Articles

Little Red Night Light Is Just Right

December 13, 2020 by 35 Comments

Don’t you hate getting up in the middle of the night to use the bathroom? The worst part is not being able to see what you’re doing, but if you turn on a light, you’ll lose your night vision. Nightlights are supposed to be the best solution, but are usually too bright for 3 AM excursions and can end up leaking light into the bedroom. What the bathroom needs is a purpose-built nightlight that uses red light so you don’t lose your night vision.

This simple, wall-mounted night light is just the thing. All it takes is two AA batteries, a resistor, a red LED, and an SPST push button. [Vchaney] even made their own battery contacts. The genius part of this build is in the adjustable LED, which is fitted into a ball that moves around in a socket so you can aim it wherever you need to see. All the files are available if you want to print one for yourself.

Those who sit might prefer to shine the light on the toilet paper roll. Here’s a smart roll holder that doubles as a night light, albeit a terribly bright one.

Do You Smell What The Magic Chef Is Cookin’?

March 19, 2020 by 6 Comments

Automata are already pretty cool, but the ones that can fool us are something extraordinary. The legendary [Greg Zumwalt] has recently turned his toy-making attentions toward illusory automata, and we think he’s off to a great start with his admirable appetizer, the Magic Chef.

The Chef aims to please, and as long as he has the power to do so, he’ll keep offering dishes from his six-item menu of hamburger, hot dog, pizza slice, BLT, sunny-side-up egg, and banded gelatinous chunk we can’t quite identify. Amazingly, this one-man restaurant does everything with a single 6VDC gear motor, some magnets, and 58 printed parts including gears, cams, and levers. The way the food carousel moves on a sort of magnetic slip ring system is the icing on the cake.

If you want to whip up a Magic Chef of your own, all the STL files are available for take-out from the Instructables page. Hungry for more details? go wash up and get situated after the break, ’cause we’re serving up a demo video with some close-up views of the inner workings. Oh, and here’s some automata-brewed coffee for dessert.

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A Useless Tomb Of Eternal Doom

October 1, 2019 by 10 Comments

It’s officially October, and that means we can start unleashing the Halloween hacks. Take for example this restless skeleton that master automaton maker [Greg Zumwalt] has doomed to spend eternity inside of a useless box. If that wasn’t enough to wake the dead, every time some joker pushes the button, these blinky lights come on. Hey, at least there’s no opera music.

The ironic thing about useless machines is that there are a ton of ways to make them. This spooktacular Halloween-themed do-nothing box doesn’t use a microcontroller, or even a 555 — it’s purely electromechanical. When the button is pressed, two AAAs power a small gear motor that simultaneously lifts the lid, raises the dead, and twists him a quarter turn so he can close the lid and put himself back to eternal rest.

The intricately-printed skeleton doesn’t really push the button — he’s far too dead and frail for that. The gear motor also turns a dual-lobe cam that activates a pair of roller switches that handle the candles and lower Mr. Bones back into his crypt. Clear as blood? Skitter past the break for a closer look at the mechanism.

Halloween or not, we love a good useless machine around these parts. Here’s one that incorporates a real candle and who could forget this octo-switched beast?

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Automatic Plant Care Minus The Microcontroller

January 19, 2015 by 8 Comments

Plants are a nice addition to most any habitat. Many of them bear flowers or attractive foliage, some of them help filter the air, and others, like aloe vera, have medicinal properties. While some plants require very little care, they all need a little moisture at some point. Overall, plant care is a bit fiddly: water them too much and you run the risk of root rot; water too little and risk death by dehydration. Hackaday alum [Kevin Darrah] would prefer not to gamble with either condition, and so in the course of a weekend’s time, he constructed a solar-powered automatic plant watering system from components he had on hand.

While he likely had a microcontroller or two lying around, he didn’t use one. His is a system of MOSFETs that trigger a motorized pump from one of those automatic bug spray bottles to draw from a reservoir and water the plant. The solar panel charges a bank of 6800µF capacitors that [Kevin] took out of an old receiver. When the desired charge is reached, the small soil sensor module is powered, assessing the moisture level. If the level is below the threshold determined by a trimmer pot, the power from the capacitor bank is dumped to the water pump and his plant gets a drink.

[Kevin]’s design deals nicely with the possible pitfalls of solar power. He’s included a 0.1µF cap to ensure latching through the system, and added a bleed resistor so that the pump is never powered unnecessarily. After running it for a couple of days, he’s already seeing moisture regulation in the soil. His complete demonstration and theory of operation is after the break. If you’re into solar power but aren’t quite ready to ditch the µC, check out this Arduino-controlled solution for thirsty tomatoes or this PIC-powered plant pacifier.

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