Add A Slide Show To Your Fish Tank

February 24, 2016 by Anool Mahidharia 11 Comments

Once in a way we get a hack that makes us wonder – why didn’t we think of that ? [hydronics] tore apart an old LCD monitor and built a fish tank around it. Not sure if the fish notice that they are swimming on the Moon, but it sure makes for an interesting fish tank display.

He starts by ripping apart an old 19″ LCD monitor and built an acrylic fish tank around the display. The backlight of the panel is fixed at the rear side of the fish tank, along with the rest of the electronics from the old monitor.

For an earlier version, he built his own back light, but the second version with the original back light turned out much better. The fish tank pieces were joined together using acrylic glue and left over night to dry, although he still needed to use some silicone to plug leaks.

A Raspberry Pi connected to the monitor’s HDMI input provides the background slide show. [Tony Rieker] helped add bubble animations via some OpenCV code running on the Pi. A live feed of the fish is overlaid on the slide show, adding a level of inception to this tricked up fish tank. The project was recently shown off at the Portland Winter Light Festival.

Continue reading “Add A Slide Show To Your Fish Tank” →

Punch Card Reader For The 10 Types Of People In The World

February 22, 2016 by Dan Maloney 7 Comments

Punch card data input is so 1890 US Census, right? Maybe not, if your goal is to educate kids about binary numbers and how they can encode characters. In which case, this paper clip and metal tape punch card reader might be just the thing you need.

Built as part of the educational outreach efforts of the MakeICT hackerspace, this project allows kids and adults to play with binary numbers and get some instant feedback. The reader itself is a simple affair of wood and plastic; bent paperclips make contact with a foil tape strip and LEDs show the state of the five input bits. A card is provided to students with spaces for the letters of a word that they want to input, along with a table to translate each letter into a number. Students use a paper punch to encode each character in binary. As the card is pulled through the reader, the letters are spoken by the Pi in turn and the whole word is pronounced at the end.

We’ll no doubt hear quibbles with the decision not to use ASCII for the character set, but we can see the logic in keeping the number of bits to a minimum and not distracting from the learning process. What’s cool about this is that it engages kids on so many levels. They learn about binary numbers, encoding systems, interfacing a computer to the real world, and if they care to delve deeper, they can learn about the code behind everything. It’s a great hook into the hacking arts.

And once the kids learn a thing or two, maybe they can use this punch-card Twitter interface to tweet their new-found knowledge.

The Raspberry Pi Zero contest is presented by Hackaday and Adafruit. Prizes include Raspberry Pi Zeros from Adafruit and gift cards to The Hackaday Store!
See All the Entries || Enter Your Project Now!

$5 VGA For Raspberry Pi

February 21, 2016 by Al Williams 51 Comments

Hackaday.io user [mincepi] wanted a VGA output on his Raspberry Pi Zero. His quest led him to design a PCB that mates with a VGA monitor and the Pi board and–according to his estimates–costs about $3.62 each (although to get that price, you have to build three).

Continue reading “$5 VGA For Raspberry Pi” →

Breathing New Life Into An Old Key

February 21, 2016 by Jenny List 13 Comments

For most of us who have experimented with Morse code, the oldest key we are likely to have used will have been a piece of military surplus kit from the Second World War era. [Kyle Gabriel] however is a lucky man. His grandfather left him his key-on-board telegraph practice set, a vintage key and telegraph sounder arrangement used to learn Morse code in the days when the telegraph was king. Rather than keep the set merely as an heirloom, [Kyle] set about bringing it up to date by interfacing it to a Raspberry Pi and writing a Morse reader program.

Along the way [Kyle] had to contend with debouncing the switching signal from the key, considering an RC network before settling on a software debounce timer. He provides a brief synopsis of the mechanics of Morse decoding software, and a demonstration of the code in action which you can see in the video below the break.

[Kyle’s] decoding software, beatbybeat, is on GitHub. We can see it will be a useful tool for anyone interested in Morse, or who is writing their own Morse software.

Morse code has featured on these pages more than a few times over the years. Of relevance to this piece are an Arduino decoding Morse code, a more up-to-date practice oscillator with a home-made key, and a couple of other vintage telegraphs reading RSS feeds and reading emails.

Continue reading “Breathing New Life Into An Old Key” →

Hacklet 96 – Pi Zero Contest Projects Week 3

February 20, 2016 by Adam Fabio 3 Comments

The calendar is rolling through the third week of the house that Hackaday and Adafruit built: The Raspberry Pi Zero Contest. We’re nearly at 100 entries! Each project is competing for one of 10 Raspberry Pi Zeros, and one of three $100 gift certificates to The Hackaday Store. This week on The Hacklet, we’re going to take a look at a few more contest entries.

[Phil “RzR” Coval] is trying to Port Tizen to the Raspberry Pi Zero. For those not in the know, Tizen is an open source operating system for everything. Billed as a go-to OS for everything from wearables to tablets to smartphones to in-vehicle entertainment systems, Tizen is managed by the Linux Foundation and a the Tizen Association. While Tizen works on a lot of devices, the Raspberry Pi and Pi 2 are still considered “works in progress”. Folks are having trouble just getting a pre-built binary to run. [Phil] is taking the source and porting it to the limited Pi Zero platform. So far he’s gotten the Yocto-based build to run, and the system starts to boot. Unfortunately, the Pi crashes before the boot is complete. We’re hoping [Phil] keeps at it and gets Tizen up and running on the Pi Zero!

Next up is [shlonkin] with Classroom music teaching aid. Guitar Hero has taught a generation of kids to translate flashing lights to playing notes on toy instruments. [Shlonkin] is using similar ideas to teach students how to play real music on a harmonica. The Pi Zero will control a large display model of a harmonica at the front of the classroom. Each hole will light up when that note is to be played. Harmonica’s have two notes per hole. [Shlonkin] worked around this with color. Red LEDs mean blow (exhale), and Blue LEDs mean draw (inhale). The Pi Zero can do plenty more than blink LEDs and play music, so [shlonkin] plans to have the board analyze the notes played by the students. With a bit of software magic, this teaching tool can provide real-time feedback as the students play.

[Spencer] is putting the Pi Zero to work as a $5 Graphics Card For Homebrew Z80. The Z80 in this case is RC2014, his DIY retro computer. RC2014 was built as part of the 2014 RetroChallenge. While the computer works, it only has an RS-232 serial port for communication to the outside world. Unless you have a PC running terminal software nearby, the RC2014 isn’t very useful. [Spencer] is fixing that by using the Pi Zero as a front end for his retro battle station. The Pi handles USB keyboard input, translates to serial for the RC2014, and then displays the output via HDMI or the composite video connection. The final design fits into the RC2014 backplane through a custom PCB [Spencer] created with a little help from kicad and OSHPark.

Finally we have [txdo.msk] with 8 Leaf Pi Zero Bramble. At $5 each, people are scrambling to build massively parallel supercomputers using the Raspberry Pi Zero. Sure, these aren’t practical machines, but they are a great way to learn parallel computing fundamentals. It only takes a couple of connectors to get the Pi Zero up and running. However, 8 interconnected boards quickly makes for a messy desk. [Txdo.msk] is designing a 3D printed modular case to hold each of the leaves. The leaves slip into a bramble box which keeps everything from shorting out. [Txdo.msk] has gone through several iterations already. We hope he has enough PLA stocked up to print his final design!

If you want to see more entrants to Hackaday and Adafruit’s Pi Zero contest, check out the submissions list! If you don’t see your project on that list, you don’t have to contact me, just submit it to the Pi Zero Contest! That’s it for this week’s Hacklet. As always, see you next week. Same hack time, same hack channel, bringing you the best of Hackaday.io!

TV Control With Hand Gestures

February 17, 2016 by Will Sweatman 12 Comments

The cell phones of yesteryear were covered in buttons. Today’s cell phones are mostly a touch display with maybe one or two buttons. As time marches on, we find ourselves using our fingers more for gestures and swipes than button pushing to control our devices. Sadly, the television remote has been stuck in an antiquated state and most are still covered in archaic buttons.

[Frederick] has decided to dig the TV remote out from the stone age and updated it to use simple gestures for control. We’ve seen gesture control before, but this one is certainly the most elegant. He’s using a Raspberry Pi with a Skywriter HAT gesture recognition board. The driver is super easy to install and can be done in a single command line. The Skywriter hat interpreters the hand gesture and the Pi fires the appropriate signal via an IR emitter. This approach made the project fairly simple to put together, with surprisingly good results.

Be sure to check out his blog for all code needed, and take a look at the video below to see the remote in action.
Continue reading “TV Control With Hand Gestures” →

A Quadcopter Controlled By A Pi Zero

February 16, 2016 by Brian Benchoff 57 Comments

Flight controllers for quadcopters and other drones are incredible pieces of engineering. Not only do these boards keep an aircraft level, they do so while keeping the drone in one place, or reading a GPS sensor and flying it from waypoint to waypoint. The latest of these flight controllers is built on everyone’s favorite $5 computer, the Raspberry Pi Zero.

The PXFmini controller and autopilot shield is the latest project from Erle Robotics that puts eight servo outputs on the Pi, barometer and IMU sensors, a power supply, and all the adapters to turn the Raspberry Pi Zero into a capable flight controller. Since the Pi Zero will have some computational horsepower left over after keeping a quadcopter level, there’s a possibility of some very cool peripherals. Erle Robotics has been working with depth cameras and Lidar on more than a few drones. This makes for some interesting applications we can only imagine now.

The schematics for the PXFmini are open source in the best traditions of the RC and drone community and will be available soon. You can check out a video of the FXPmini flying around an office below.

Continue reading “A Quadcopter Controlled By A Pi Zero” →