Traditionally, the useless machine is a simple one that invites passersby to switch it on. When they do, the machine somehow, some way, turns itself off; usually with a finger or finger-like object that comes out from the box in what feels like an annoyed fashion. Honestly, that’s probably part of what drives people to turn them on over and over again.

But [Bart Blankendaal] has managed to turn the useless machine on its head. When this machine is switched to the on position, unseen forces inside the box will spin the toggle switch around 180° to the off position.

What’s really happening is that an Arduino is getting a signal from the toggle switch, and is then rotating it on a ball bearing with a stepper motor driven through an H-bridge.

It shouldn’t be too hard to make one of these yourself, given that [Bart] has provided the schematic and STLs. If we weren’t living in such touchy times, we might suggest building one of these into your Halloween candy distribution scheme somehow. Sell the switch as one that turns on a candy dispenser, and then actually dispense it after three or five tries.

Many see useless machines as tangible examples of existential quandary. Here is one that takes that sentiment a bit further by snuffing out a candle.

Want to take that annoyingly productive coworker down a notch? Yeah, us too. How dare they get so much done and be so happy about it? How is it possible that they can bang on that keyboard all day when you struggle to string together an email?

The Slippy Slapper is a useless machine that turns people into useless machines using tactics like endless distraction and mild physical violence. It presses your buttons by asking them to press buttons for no reason other than killing their productivity. When they try to walk away, guess what? That’s another slappin’. Slippy Slapper would enrage us by proxy if he weren’t so dang cute.

You’re right, you don’t need an Arduino for this. For peak inefficiency and power consumption, you actually need four of them. One acts as the master, and bases its commands to the other three on the feedback it gets from Slippy’s ultrasonic nostrils. The other three control the slappin’ servos, the speakers, and reading WAV files off of the SD card. Slap your way past the break to see Slippy Slapper’s slapstick demo.

Need to annoy a group of coworkers all at once? Slip a big bank of useless machines into the conference room while it’s being set up.

GeekCon participants add a switch and actuator to a HAL 9000 model for the world’s largest “leave-me-alone box.”

You’ve probably seen the silly boxes that when you flip a switch to turn it “on,” an arm comes out to turn itself “off” again. At this year’s GeekCon Makers conference, participants decided to make a useless machine, but in place of a simple box, they made a model of the HAL 9000 computer from 2001: A Space Odyssey.

Rather than the normal “useless” configuration, it turns itself “on” instead of “off” in an apparent nod to the fact that the computer didn’t want to be disconnected in the movie. One Arduino controls a projector for the “eye” assembly, while another takes care of the servos and audio. HAL’s sounds are stored on an SD card inside an Adafruit Music Shield.

Behind the eye, made out of round lamp and a red plastic diffuser, there is a projector. The projector is connected to Arduino TVout which only outputs a white filled circle that also changes its diameter based on microphone input. Having the circle moving according to the sounds gives HAL’s eye more realistic look.

The second Arduino was in charge of servos and audio. We divided the tasks to two Arduino Uno to avoid collisions in PINs requirements.

You can find more information on this project on its blog and in Hackaday’s recent writeup. If you just want to see the Arduino code, it’s available here.

(Photos: Rafael Mizrahi)

In a time when we’re inundated with talk of an impending AI apocalypse it’s nice to see an AI that’s intentionally useless. That AI is HAL 9000. No, not the conflicted HAL from the movie 2001: A Space Odyssey but the World’s Biggest AI Useless Machine HAL built by [Rafael], [Mickey] and [Eyal] for GeekCon 2016 in Israel.

Standing tall, shiny and black, the box it’s housed in reminds us a bit of the monolith from the movie. But, in a watchful position near the top is HAL’s red eye. As we approach, HAL’s voice from the movie speaks to us asking “Just what do you think you’re doing, Dave?” as the eye changes diameter in keeping with the speech’s amplitude. And at the bottom is a bright, yellow lever marked ON, which of course we just have to turn off. When we do, a panel opens up below it and a rod extends upward to turn the lever back to the ON position.

Behind the scenes are two Arduinos. One Arduino manages servos for the panel and rod as well as playing random clips of HAL from the movie. The other Arduino uses the Arduino TVout library to output to a projector that sits behind the red diffuser that is the eye. That Arduino also takes input from a microphone and based on the amplitude, has the projector project a white circle of corresponding diameter, making the eye’s appearance change. You can see all this in action in the video after the break.

Paradoxically, useless machines serve the purpose of being fun and we’ve seen other fun ones in the past, such as one that snuffs out a candle the moment you light it and another that turns the pages of a book and scans them, with wooden eyes. So check them out while not wasting time having fun.