Guitar Hero Robot Actually Shreds

May 3, 2021 by Matthew Carlson 12 Comments

Once a popular craze, most of the public has sold or stashed away their plastic video game instruments and forgotten the likes of Guitar Hero and Rockband. Having never been quite satisfied with his scores, [Nick O’Hara] set out to create a robot that could play a Guitar Hero controller. It would be easy enough to use transistors to actuate the buttons or even just a Teensy to emulate a controller and have it play the perfect game, but [Nick] wanted to replicate what it was really like to play. So after burning out a fair number of solenoids (driving them over spec) and learning on his feet, [Nick] slowly began to dial in his robot, Jon Bot Jovi.

The brains of the bot are a Raspberry Pi running some OpenCV-based code that identifies blobs of different colors. The video feed comes from a PS2 via an HDMI capture card. Solenoids are driven via an 8 channel driver board, controlled by the Pi. While it missed a few notes here and there, we loved seeing the strumming solenoid whammy rapidly on the strummer. All in all, it’s a great project, and we love the design of the robot. Whether played by a robot, turned into a synthesizer, or recreated from toy pianos and mechanical keyboards, Guitar Hero controllers offer many hacking opportunities.

Continue reading “Guitar Hero Robot Actually Shreds” →

This DIY Split-Flap Display Does Both Time And Weather

April 29, 2021 by Donald Papp 5 Comments

With little more than four economical stepper motors, a Raspberry Pi Zero, and a 3D printer, [Thomas Barlow] made himself an awfully slick Smart Flip Clock that can display not only the time, but also weather data as well. This is done by adding a few extra graphics to some of the split-flaps, so numbers can also be used to indicate temperature and weather conditions succinctly. Displaying the time has to do without a colon (so 5:18 displays as 518), but being able to show temperature and weather conditions more than makes up for it.

According to the project’s GitHub repository, it looks as though each split-flap has thirteen unique positions. The first ten are for numerals 0 through 9, and the rest are either blank, or used to make up a few different weather icons with different combinations. A Python script runs on the Raspberry Pi and retrieves weather data from OpenWeather, and the GPIO header drives the display via four geared stepper motors and driver boards. The rest of the hardware is 3D printed, and [Thomas] helpfully provides CAD models in STEP format alongside the STL files.

The basic design of a split-flap display is really quite versatile, and enterprising hackers have been putting delightful new twists on them for years. There has been a split-flap display used as a kind of flip-book animation, and we’ve also had the pleasure of seeing an entire Tarot deck used for esoteric, automated readings.

Run Out Of GPIO On Your Pi? Don’t Despair!

April 28, 2021 by Jenny List 25 Comments

When the first Raspberry Pi rolled off the production line back in 2012 it sported a 26-pin expansion header that seemed to conceal endless possibilities. A later upgrade to the 40-pin header we have today unleashed a few more precious interfaces, but even then it’s still possible to run out. This was the problem faced by [woj], who needed a PWM line to drive a cooling fan but whose other work had used everything on the header. The solution? Dive into the other connectors on board looking for an unused GPIO.

Every full-sized Pi has a connector for the camera and the LCD screen, and to operate some of the functions of those peripherals they contain a few extra GPIOs that aren’t normally used by end users. If the camera or LCD is not being used then these lines are potentially up for grabs. In particular there’s a GPIO that turns the camera on or off that’s relatively easy to solder a wire to, and it was this one that fed the PWM line.

There are of course a few other ways to find some more lines on a Pi and indeed almost any microcontroller, with one of the many types of GPIO expansion chips. This trick is a particularly simple one though. and perhaps unsurprisingly it has surfaced here before.

Ask Hackaday: Why Make Modular Hardware?

April 27, 2021 by Adam Zeloof 33 Comments

In the movies, everything is modular. Some big gun fell off the spaceship when it crashed? Good thing you can just pick it up and fire it as-is (looking at you, Guardians of the Galaxy 2). Hyperdrive dead? No problem, because in the Star Wars universe you can just drop a new one in and be on your way.

Of course, things just aren’t that simple in the real world. Most systems, be they spaceships or cell phones, are enormously complicated and contain hundreds or thousands of interconnected parts. If the camera in my Samsung phone breaks, I can’t exactly steal the one from my girlfriend’s iPhone. They’re simply not interchangeable because the systems were designed differently. Even if we had the same phone and the cameras were interchangeable, they wouldn’t be easy to swap. We’d have to crack open the phones and carefully perform the switch. Speaking of switches, the Nintendo Switch is a good counterexample here. Joycon break? Just buy a new one and pop it on.

What if more products were like the Nintendo Switch? Is its modularity just the tip of the iceberg?

Continue reading “Ask Hackaday: Why Make Modular Hardware?” →

Paper Pi Is An Ergonomic Cyberdeck Meant For Thumbs

April 27, 2021 by Kristina Panos 7 Comments

What’s the fastest way to master console stuff like screen or emacs? Force yourself to use it exclusively, of course. But maybe you’d be tempted to cheat with a desktop. We know we would be. In that case, you ought to build a console-only cyberdeck like this sweet little thing by [a8skh4].

This cyberdeck serves another purpose as well — the keyboard layout is Miryoku, so [a8ksh4] can get more practice with that at the same time. Fortunately, the layout is built for emacs.

Inside is a Raspberry Pi 4 and what looks to be an Arduino handling the keyboard input. The Paper Pi spotlights a 4.2″ e-ink screen between a split thumb keyboard that’s made of soft, silent, tactile switches.

Since they’re SMD, [a8ksh4] made clever use of header pins to get them to work with protoboard. As much as we love the keyboard, it would be awesome to see a few switches on the shoulders or even the back that make use of the rest of the fingers. Check out more build pictures in the gallery.

We love to see cyberdecks with split keyboards, because you shouldn’t have to sacrifice ergonomics in a portable computer. Here’s one that comes in three pieces, making it easy to get the spacing between the halves just right.

Via r/cyberdeck

Keep In Touch With Grandma, With This Lo-Tech Interface

April 25, 2021 by Jenny List 17 Comments

We have so many options through which to communicate with our friends and relatives during the lockdown, thanks to our smartphones and the number of apps that serve all possible needs. Impressive as they are though, a smartphone is not suitable for everyone. In particular older people can find them less easy to use, and the consequent loss of communication ability is addressed by [Manu] with the Yayagram, described in a thread of Spanish-language Tweets and later the thread was translated into English.

On the top of the box is a microphone with push-to-talk switch, a small thermal printer, and a set of 1/4″ jack sockets with associated jump lead. Each socket corresponds to a relative, and an audio message to that relative can be posted via Telegram simply by speaking into the microphone with the button pressed. Replies are then printed through the thermal printer. Meanwhile behind the scenes is a Raspberry Pi holding it all together.

We like the simplicity of the interface, and who wouldn’t want to ensure that their older relatives were able to keep in touch! But while the jump lead is a neat touch, we hope it’s not too difficult for extremely frail hands. It’s certainly not the first accessibility project for older people that we’ve seen.

Pi-Based Spectrometer Puts The Complexity In The Software

April 23, 2021 by Dan Maloney 43 Comments

Play around with optics long enough and sooner or later you’re probably going to want a spectrometer. Optical instruments are famously expensive, though, at least for high-quality units. But a useful spectrometer, like this DIY Raspberry Pi-based instrument, doesn’t necessarily have to break the bank.

This one comes to us by way of [Les Wright], whose homebrew laser builds we’ve been admiring for a while now. [Les] managed to keep the costs to a minimum here by keeping the optics super simple. The front end of the instrument is just a handheld diffraction-grating spectroscope, of the kind used in physics classrooms to demonstrate the spectral characteristics of different light sources. Turning it from a spectroscope to a spectrometer required a Raspberry Pi and a camera; mounted to a lens and positioned to see the spectrum created by the diffraction grating, the camera sends data to the Pi, where a Python program does the business of converting the spectrum to data. [Les]’s software is simple by complete, giving a graphical representation of the spectral data it sees. The video below shows the build process and what’s involved in calibrating the spectrometer, plus some of the more interesting spectra one can easily explore.

We appreciate the simplicity and the utility of this design, as well as its adaptability. Rather than using machined aluminum, the spectroscope holder and Pi cam bracket could easily be 3D-printer, and we could also see how the software could be adapted to use a PC and webcam.

Continue reading “Pi-Based Spectrometer Puts The Complexity In The Software” →