Raspberry Pi

1848 Articles

Robot Solves Sudoku On Paper

July 10, 2017 by 13 Comments

Sudoku is a great way to pass some time, especially on a long flight. However, we don’t think the airlines will let [Sanahm] board with his sudoku-solving robot. The basic machine looks like a 2D plotter made with aluminum extrusion, with the addition of a Raspberry Pi and a camera. The machine can read a sudoku puzzle, solve it, and then fill in the puzzle with a pen. Unlike humans, it should never need to erase its work.

The software uses OpenCV to process the camera data, find the grid, and the cells provided by the puzzle. TensorFlow recognizes the numbers. From there, it is all just math to solve the puzzle. Once solved, the plotter part of the robot takes over and fills in the blanks. After all that, this seems like the easy part.

Continue reading “Robot Solves Sudoku On Paper” →

Making A Small-Scale Brewery With A Raspberry Pi And Python

July 9, 2017 by 22 Comments

No doubt many Hackaday readers will have tried their hand at home brewing. It’s easy enough, you can start with a can of hopped malt extract and a bag of sugar in a large bucket in your kitchen and achieve a decent enough result. Of course, once you get the taste it’s a field of infinite possibilities, so many enthusiasts go further into the realm of beer making with specialty ingredients and carefully controlled mash tuns.

Such an inductee into the brewery arts is [Christopher Aedo], who has documented his automated brewing system driven by a Raspberry Pi running CraftBeerPi. And it’s an impressive setup, with boil kettle, mash tun, and heat exchanger, a 5KW heating element, and all associated valves, pipes, pumps, and sensors. This ensures consistency and fine control over temperature over the long-term at all stages of the brew, something that would be very difficult to achieve manually at this scale.

The whole brewery is mounted on a cart for portability and has been used for a lot of brew cycles of many different styles. We can’t help a touch of envy at the array of beer taps in his kitchen.

Over the years we’ve brought you a few brewing projects. Another Pi-based setup graced these pages in 2012, as did a brewery using a Lego Mindstorms controller. Top marks go though to the brewer who fought his beer belly through brewing machinery powered by an exercise bike.

Via Recantha.

Tweet The Power Of Lightning!

July 8, 2017 by 15 Comments

How quickly would you say yes to being granted the power to control lightning? Ok, since that has hitherto been impossible, what about the lesser power of detecting and tweeting any nearby lightning strikes?

Tingling at the possibility of connecting with lightning’s awesome power in one shape or another, [Hexalyse] combined AMS’s lightning sensor chip with a Raspberry Pi and a whipped up a spot of Python code to tweet the approach of a potential storm. Trusting the chip to correctly calculate strike data, [Hexalyse]’s detector only tweets at five minute intervals — because nobody likes a spambot — but waits for at least five strikes in a given time frame before announcing that a storm’s-a-brewing. Each tweet announces lightning strike energy, distance from the chip, and number of strikes since the last update. If there haven’t been any nearby lightning strikes for an hour, the twitter feed announces the storm has passed.

It just so happened that as [Hexalyse] finished up their project, a thunderstorm bore down on their town of Toulouse, France putting their project to the test — to positive success. Check out the detector’s tweets (in French).

We recently featured another type of lightning detector that auto-deploys a lightning rod once a storm arrives!

Atari 2600 In A Game Cartridge

July 8, 2017 by 21 Comments

[PJ Evans] had a ruined game cartridge lying around, just waiting for a project. As Activision’s F-14 Tomcat game for the Atari 2600 console, it seemed ripe for use as a project enclosure of some sort. When he came across a couple of 9-pin D-sub joystick ports, he had an idea. He realized his Rasperry Pi Zero could fit inside the cartridge. Add a power button, TV color selector, difficulty switch, as well as select and reset buttons, and you have an emulator.

[PJ]’s Pi Zero had more than enough GPIO pins to accommodate all of those buttons and switches plus a bunch more for the joysticks. Why not put the emulator inside a game cartridge? In terms of software [PJ] looked into Adafruit’s Retro Gaming with Raspberry Pi resource, which has tons of suggestions for setting up game emulators. He decided on the RetroPie operating system to help him map out all of the pins, with Stella doing the actual Atari 2600 emulation.

Thanks, @seb_ly]!

Hacking Into…. A Wind Farm?

July 6, 2017 by 21 Comments

Pick a lock, plug in a WiFi-enabled Raspberry Pi and that’s nearly all there is to it.

There’s more than that of course, but the wind farms that [Jason Staggs] and his fellow researchers at the University of Tulsa had permission to access were — alarmingly — devoid of security measures beyond a padlock or tumbler lock on the turbines’ server closet. Being that wind farms are generally  in open fields away from watchful eyes, there is little indeed to deter a would-be attacker.

[Staggs] notes that a savvy intruder has the potential to shut down or cause considerable — and expensive — damage to entire farms without alerting their operators, usually needing access to only one turbine to do so. Once they’d entered the turbine’s innards, the team made good on their penetration test by plugging their Pi into the turbine’s programmable automation controller and circumventing the modest network security.

The team are presenting their findings from the five farms they accessed at the Black Hat security conference — manufacturers, company names, locations and etc. withheld for obvious reasons. One hopes that security measures are stepped up in the near future if wind power is to become an integral part of the power grid.

All this talk of hacking and wind reminds us of our favourite wind-powered wanderer: the Strandbeest!

[via WIRED]

A Shocking Wizard Duel

July 4, 2017 by 27 Comments

You’ve probably heard of Arthur C. Clarke’s third law, suggesting that any sufficiently advanced technology is indistinguishable from magic. Taking this literally and in the best possible way, [Allen Pan] of [Sufficiently Advanced] is using readily available technology to simulate magical wizarding duels in the fashion of Harry Potter.

Entitled the Wizard Analogue No-Magic Dueling Simulator — or W.A.N.D.S. for short — is a slightly more interactive version of laser tag. It’s especially engaging because your body is on the line. A Raspberry Pi using Google’s speech recognition service listens for the spell names and — remember, pronunciation is key — fires off the spell from an infrared LED tipped wand. Each duelist has five spells at their disposal, but their accuracy is up to you.

Once your opponent’s receiver registers a hit, an Arduino triggers transcutaneous electrical nerve stimulation (TENS) devices which sends pulses to various regions on the body to simulate the spell’s effect. What’s a few electrical shocks between wizards, eh?

As a defense from the constant barrage, the spell Protego — aimed at one’s own sensor — grants a few seconds immunity; however all spells have a built-in cool-down to prevent their abuse and an LED on the wand indicates when they’re ready to be used.

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Softly To Sleep, My Raspberry Pi

July 4, 2017 by 45 Comments

For all their capacity, shutting down a Raspberry Pi can be a bothersome routine depending on how you have it set up — historically and abrupt cut to the power risks corrupting the SD card. [madlab5] had to make a few changes to a Pi running in headless mode, requiring them to access it externally to shut it down to prevent any damage from pulling the plug. So, why not take the opportunity to whip up a soft shut-down switch?

This is a great beginner project to get one accustomed to working with a Pi. With this in mind, [madlab5] went through two revisions of this idea: the simple way, and the fun way. For the simple way just press the button and the Pi activates a script which shuts it down in thirty seconds. Job done. But, realizing there may be a few circumstances where they’d need more functionality, [madlab5] decided to take a second swing at this.

[madlab5]’s fun way involves a button with a built-in LED and a speaker to blare an announcement that the Pi will self destruct shut down after a short time. Setting the switch up this way takes a little more doing, but you get to add a little more character to your Pi with a custom shutdown report, as well as the option to cancel an accidental button-press.

For any newbies out there, [madlab5] is kind enough to provide their code and diagrams in their blog post. If remotes are more your thing, we have also featured a similar beginner project to shut down your Pi.

[via /r/Raspberry_Pi_Projects]