The Raspberry Pi was initially developed as an educational tool. With its bargain price and digital IO, it quickly became a hacker favorite. It also packed just enough power to serve as a compact emulation platform for anyone savvy enough to load up a few ROMs on an SD card.
Video game titans haven’t turned a blind eye to this, realising there’s still a market for classic titles. Combine that with the Internet’s love of anything small and cute, and the market was primed for the release of tiny retro consoles.
Often selling out quickly upon release, the devices have met with a mixed reception at times due to the quality of the experience and the games included in the box. With so many people turning the Pi into a retrogaming machine, these mini-consoles purpose built for the same should have been immediately loved by hardware hackers, right? So what happened?
We know that some in the audience will take issue with calling a Raspberry Pi in a 3D-printed case the “World’s Smallest iMac”, but you’ve got to admit, [Michael Pick] has certainly done a good job recreating the sleek look of the real hardware. While there might not be any Cupertino wizardry under all that PLA, it does have a properly themed user interface and the general aversion to external ports and wires that you’d expect to see on an Apple desktop machine.
The clean lines of this build are made possible in large part by the LCD itself. Designed specifically for the Raspberry Pi, it offers mounting stand-offs on the rear, integrated speakers, a dedicated 5 V power connection, and a FFC in place of the traditional HDMI cable. All that allows the Pi to sit neatly on the back of the panel without the normal assortment of awkward cables and adapters going in every direction. Even if you’re not in the market for a miniature Macintosh, you may want to keep this display in mind for your future Pi hacking needs.
Well, that’s one way to do it.
Despite this clean installation, the diminutive Raspberry Pi was still a bit too thick to fit inside the 3D-printed shell [Michael] designed. So he slimmed it down in a somewhat unconventional, but admittedly expedient, way. With a rotary tool and a steady hand, he simply cut the double stacked USB ports in half. With no need for Ethernet in this build, he bisected the RJ-45 connector as well. We expect some groans in the comments about this one, but it’s hard to argue that this isn’t a hack in both the literal and figurative sense.
We really appreciate the small details on this build, from the relocated USB connectors to the vent holes that double as access to the LCDs controls. [Michael] went all out, even going so far as to print a little insert for the iconic Macintosh logo on the front of the machine. Though given the impressive work he put into his miniature “gaming PC” a couple months back, it should come as no surprise; clearly this is a man who takes his tiny computers very seriously.
The Raspberry Pi is a hugely popular platform for emulating older consoles, with the RetroPie framework making it easy to get started in no time at all. Often, these single board computers get built into fun arcade boxes or replica console shells to add to the charm. That’s all been done, so instead, [Cedishappy] decided to go in his own direction – resulting in the wonderful Watermelon Gameboy.
What sounds like a trivial exercise of building a RetroPie rig in a unique enclosure actually comes with some engineering challenges. The basics are all pretty standard – GPIO pins interfacing buttons, a speaker and the screen, emulating a Gameboy Advance. But the mechanical implementation is more complex. The watermelon is first cut open, having its red flesh removed, leaving just the rind. Paper and cardboard templates are then used to make holes for the buttons and screen. Unfortunately, hot glue doesn’t work on watermelon, so instead, toothpicks were used to hold the screen and speaker in place. To protect the electronics from the moist melony environment inside, clear food wrap was applied to the Raspberry Pi and other components where needed.
[Cedishappy] goes above and beyond with the project video charmingly showing the reactions of bystanders to the contextually confusing game system. The combination of electronics with fruit and vegetables is an area we don’t see explored often enough; our own [Mike Szczys] built a magnificent LED Jack-o-Lantern that really looks the business. Video after the break.
Sunrises and sunsets hardly ever disappoint. Still, it’s difficult to justify waking up early enough to catch one, or to stop what you’re doing in the evening just to watch the dying light. If there’s one good thing about CCTV cameras, it’s that some of them are positioned to catch a lovely view of one of the two, and a great many of them aren’t locked down at all.
What do you get when you add a thermal camera, a software-defined radio dongle, and a battery to a Raspberry Pi? If you are [saveitforparts] you make a tricorder for sniffing radio signals and viewing heat signatures. He admits, the videos (see below) aren’t exactly a “how-to” but it will still give you some ideas for your next build.
You can sense the frustration with some Linux configuration issues, but [saveitforparts] admits he isn’t a Linux or Raspberry Pi guru. Version 1 seemed to be a bit of a prototype, but version 2 is more polished. We still aren’t sure we’d see Spock carrying a case like that, but some 3D printing could spiff that right up.
Of course, a real tricorder is a McGuffin that does whatever the plot calls for. This one is a bit more practical, but it can monitor thermal and RF energy and could accommodate more sensors. This is a great example of a project that would have been very hard to do in the past but is much easier today. The availability of cheap computers and ready-made modules along with associated software open up many possibilities.
If you want to do your own Tricorder hacking you could take over a commercial model. Then again, there’s an official replica on its way that seems like it might have some similar features.
Three students were a little sad when NASA’s Opportunity rover went silent after 15 years on the Martian surface. So they decided to build their own rover inspired by Opportunity to roam their backyards using an off-the-shelf robot chassis, a Raspberry Pi, and the usual list of parts like motors, H-bridges, and batteries.
Like the real rover, the vehicle uses a rocker-bogie system, although it is a little less complex than the version NASA sent blasting off towards the Red Planet. The plucky vehicle comes complete with miniature solar panels to recharge its onboard battery, courtesy of some dollar-store garden lights. A pair of videos after the break show how the rover is controlled, as well as the view sent back from its onboard camera.
The rover ran a simulated Mars mission as part of a school project where it had to find an object and transmit an image of it back to home base, and by the looks of it, is was a rousing success. But the young explorers aren’t resting on their laurels, and are already working on a second version of their exploration vehicle that can operate in inclement weather and includes some new tools such as a robotic arm and infrared illumination for low-light imaging.
It isn’t that hard to assemble an array of Raspberry Pi boards and there are several reasons you might want to do so. The real trick is getting power to all of them and cooling all of them without having a mess of wires and keeping them all separated. The ClusterCTRL stack lets you stack up to five Raspberry Pi boards together. The PCB aligns vertically along the side of the stack of Pis with sockets for each pin header. Using a single 12 to 24V supply, it provides power for each board, a USB power connection, and provisions for two fans. There is also a USB port to control the fans and power.
There’s also a software component to deliver more granular control. Without using the software, the PI’s power on in one second and monitor a GPIO pin to control the fans. With the software, you can turn on or off individual nodes, gang the two fans to turn on together, and even add more stacks.
There is a case that you can print from STL files, although you can buy them preprinted on the Tindie listing where the bulk of information on ClusterCTRL is found. You could also have a 3D printing vendor run off a copy for you if you’d rather.
The power supply is a 10A 5.1V DC to DC converter. That works out to 2A per Pi and 51W total. The power supply for the input, then, needs to be enough to cover 51W, the power for the fans, and some overhead for regulator inefficiency and other small overhead.
We’ve seen a lot of Pi clusters over the years including one that is a good learning tool for cluster management. Of course, there’s always the Oracle cluster with 1,060 boards, which is going to take a bigger power supply.
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