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Smartphone Controlled Periodic Table Of Elements

January 16, 2018 by 14 Comments

It wouldn’t be much of a stretch to say that here at Hackaday, we’re about as geeky as they come. Having said that, even we were surprised to hear that there are people out there who collect elements. Far be it from us to knock how anyone else wishes to fill their days, but telling somebody at a party that you collect chemical elements is like one step up from saying you’ve got a mold and fungus collection at home. Even then, at least a completed mold and fungus collection won’t be radioactive.

But if you’re going to spend your spare time working on a nerdy and potentially deadly collection, you might as well put it into an appropriate display case. You can’t just leave your Polonium sitting around on the kitchen counter. That’s the idea behind the interactive periodic table built by [Maclsk], and we’ve got to admit, if we get to put it in a case this awesome we might have to start our own collection.

A large portion of this project is building the wooden display case itself as, strangely enough, IKEA doesn’t currently stock a shelving unit that’s in the shape of the periodic table. The individual cells and edge molding are made of pine, the back panel is MDF, and the front of the display is faced off with thin strips of balsa to cover up all the joints. Holes were then drilled into the back of each cell for the LED wiring, and finally the entire frame was painted white.

Each cell contains an WS2812B RGB LED, which at maximum brightness draws 60mA. Given the 90 cells of the display case, [Maclsk] calculated a 5.4A power supply would be needed to keep everything lit up. However, he found a 4A power supply that made his budget happier, which he reasons will be fine as long as he doesn’t try to crank every cell up to maximum at the same time. Control for the display is provided by an Arduino Nano and HC05 Bluetooth module.

The final piece of the project was the Android application that allows the user to control the lighting. But it doesn’t just change colors and brightness, it’s actually a way to visualize information about the elements themselves. The user can do things like highlight certain groups of elements (say, only the radioactive ones), or light up individual cells in order of the year each element was discovered. Some of the information visualizations are demonstrated in the video below, and honestly, we’ve seen museum displays that weren’t this well done.

We last caught up with [Maclsk] when he created a very slick robotic wire cutting machine, which we can only assume was put to work for this particular project. Too bad he didn’t have a robot to handle the nearly 540 soldering joints it took to wire up all these LEDs.

[via /r/DIY]

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Color Changing Clock Gets A Pi Zero Heart

January 10, 2018 by 12 Comments

Hackaday reader [Don] dropped by the tip line recently to let us know about the latest version of his color-changing LCD clock project. This is his second version of the hardware which makes some pretty big improvements over the original, including moving from the Pi B to the Pi Zero and an internal simplification of the wiring. He mentions the next revision of the project will focus on Google Home integration, which should be interesting to see.

As a father of two pre-school age children, he was looking for a way to help his kids understand the concept of time and scheduled activities. Colors and shapes come fairly easy to children of this age, but time and how it relates to the day is a bit more difficult for them especially as their comprehension of numbers is still developing. [Don] reasoned that even if they couldn’t read the numbers on the clock yet, if he had the display change colors to indicate different periods of the day (sleep, play, cleanup, etc), it would not only keep them on schedule, but reinforce the meaning of the numbers on the screen.

ShiftBrite installed in the projector.

The project was made infinitely easier by a lucky find at a local retailer. For $10 he got a kid-friendly looking clock that utilized a simple projector to backlight the LCD display. This meant [Don] would just need to swap out the stock lighting module for a controllable RGB LED, and the hardware modifications would essentially be complete.

Even the Pi Zero fits perfectly inside the case of the clock, the only modification necessary was cutting a little hole in the back for the Pi’s micro USB port. His earlier version used an external Pi B connected to the clock via CAT5, so getting it all integrated into the one device is a huge improvement, especially when little kids are involved. Moving the Pi and its 5 V pins into the clock itself also allowed [Don] to drop the voltage regulator required previously.

With the basic hardware for a color changing LCD clock together, the rest of the project was just a matter of software. After some research, [Don] came across RPi-ShiftBrite by [Hive13] and made his own fork which added some features necessary for his project, namely the ability to quickly set the ShiftBrite to a specific color on the command line. To schedule the color changes, he used the very slick minicron: a web-based tool to create and monitor Linux cron jobs.

The Pi itself does not actually interface with the clock, and with no onboard RTC it’s necessary to keep it updated with NTP or else the times will become desynchronized. It can be necessary to sync the Pi’s clock to the Internet as often as every hour to make sure the colors shift at the appropriate times. The addition of a RTC module like the DS1307 could alleviate this issue and might be something to consider for a future revision.

All told, a fantastic project and something we’ll be sure to keep our eyes on as it progresses. We’ve seen our share of unique Raspberry Pi powered clocks, and even a few color changing ones, but this approach is easily the most straight-forward we’ve seen.

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Programmable Christmas Tree Is A JavaScript Interpreter

December 24, 2017 by 4 Comments

Here at Hackaday, we find Christmas time very exciting because it means an influx of holiday-themed hacks that really help us get into the festive mood. [Andrew’s] programmable Christmas tree hosted at HackMyXmas is certainly one of our favorites. The project consists of a 500 RGB LEDs wrapped around a typical Christmas tree and controlled by a Teensy.  However, not settling for the typical, simple and cyclical pattern for the LEDs, [Andrew] decided the tree had to be programmable of course! So, a single board computer (a C.H.I.P) running Linux was used to provide a Wifi connection and a web server to easily program the tree.

This is where things get very interesting. The C.H.I.P board hosts a comprehensive website that conveniently gives you the option to program the LEDs using either, Scratch like draggable blocks (using Googles Blockly) or even pure JavaScript. Once the perfect pattern is conceived, you can test run it on the online simulator or even send it off straight to the Tree, watching it blink in all its glory on the provided live stream.

We applaud [Andrew] mammoth effort for invoking programming in such a fun way! You can check out the live stream of [Andrew]’s Christmas tree below.

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Pi Replaces Keiko-chan

November 30, 2017 by 20 Comments

[Tobias Kuhn] and a handful of colleagues at his workplace built Crystal Signal Pi, a Raspberry Pi based low-cost alternative for a notification device that provides visual, audio and network warnings about server problems. [Tobias] works for a Japanese company where it is critical for their servers to keep humming nicely all the time. Any emergencies or error conditions must be broadcast immediately so the technicians can fix it ASAP. Network enabled warning light stalks are used to provide these alerts. A local company produces a series of indicator and hazard warning lights which are colloquially called as Keiko-chan. These are similar to the hazard warning tower lights commonly fixed on machines on factory floors or many kinds of vehicles such as fork lifts. The Kieko-chans add a few bells and whistles making them more suitable for use in the server data centre — a Gigabit LAN port for wired networks and a USB port for WiFi modules. So, besides visual and audio warnings, it can also transmit messages over the network to alert the maintenance folks. Using this commercial solution should not have been a problem were it not for their rather hefty price tag of almost $500 per pop.

So [Tobias] decided to build his own warning lights based around the Raspberry Pi. After two rounds of prototypes, a simple HAT was designed that could be plugged in to a Pi. Details of the hardware are sketchy, but it’s simple enough to figure out. The part list consists of a PLCC-6 style RGB LED, three transistors to drive the three LED pins, a voltage regulator with a couple of electrolytic capacitors and a large push button. A simple acrylic case, and an acrylic cylinder mounted on top of the RGB LED creates a nice edge lit effect for the indicator.

The code for the Crystal Pi is hosted on Github, and includes handy scripts to make installation easy. Once installed, the Crystal Pi can be accessed and controlled either through a web-based GUI or via the API. There are some more interesting features already implemented or scheduled for later, so do check out the blog and the repository for more. Check out the video below to see the Crystal Pi in action.

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Neural Network Really Ties The Room Together

October 27, 2017 by 21 Comments

If there’s one thing that Hollywood knows about hackers, it’s that they absolutely love data visualizations. Sometimes it’s projected on a big wall (Hackers, WarGames), other times it’s gibberish until the plot says otherwise (Sneakers, The Matrix). But no matter what, it has to look cool. No hacker worth his or her salt can possibly work unless they’ve got an evolving Venn diagram or spectral waterfall running somewhere in the background.

Inspired by Hollywood portrayals, specifically one featured in Avengers: Age of Ultron, [Zack Akil] decided it was time to secure his place in the pantheon of hacker wall visualizations. But not content to just show meaningless nonsense on his wall, he set out to create something that was at least showing actual data.

[Zack] created a neural network to work through multi-label classification data in Python using the scikit-learn machine learning suite. The code takes the values from the neutral network training algorithm and converts them to RGB colors by way of an Arduino. Each “node” in the neutral network is 3D printed in translucent filament, and fitted with an RGB LED module. These modules are then connected to each other via side-glow fiber optic tubes, so that the colors within the tubes are mixed depending on the colors of the nodes they are attached to. This allows for a very organic “growing” effect, as colors move through the network node-by-node.

In the end this particular visualization doesn’t really mean anything; the data it’s working on only exists for the purposes of the visualization itself. But [Zack] succeeded in creating a practical visualization of machine learning, and if you’re the kind of person who needs to keep tabs on learning algorithms, some variation of this design may be just what you’re looking for.

If AI isn’t your thing but you still want a wall of RGB LEDs, maybe you can use this phased array antenna visualizer instead. If you’re really hip, maybe you’ll go the analog route and put a big gauge on the wall.

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LED Princess Dress Also Lights Up Girl’s Face

September 30, 2017 by 14 Comments

We’re pretty sure that [Luke] took Uncle of the Year last Halloween when he made an RGB LED princess dress for his niece. He recently found the time to document the build with a comprehensive how-to that’s just in time for Halloween ’17.

[Luke] made the system modular so that his niece could use it with any dress. The RGB LED strips are actually fastened down the inside of a petticoat — a fluffy, puffy kind of slip that’s worn underneath the dress. The LEDs face in toward the body, which helps diffuse the light. [Luke] first attached the strips with their own adhesive and then spent a lot of time sewing them down so they stayed put. At some point, he found that hot glue worked just as well.

The coolest part of this project (aside from the blinkenlights of course) is the power source. [Luke] used what he already had lying around: an 18V Ryobi battery pack. He wired a step-converter to it using a printed cap from Shapeways that’s designed to connect metal clips to the battery contacts. This cap really makes these packs useful for a lot of projects that need long-lasting portability.

These batteries are rated for 240W, which is overkill considering the load. But there’s a reason: it keeps heat to a minimum, since the electronics are hidden inside a cute little backpack. Speaking of cute, you can see his niece model the dress after the break.

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Sense Hat Comes Alive

May 27, 2017 by 11 Comments

Remember the Raspberry Pi Sense Hat? Originally designed for a mission to the International Space Station, the board has quite a few sensors onboard as well as an 8×8 RGB LED matrix. What can you do with an 8×8 screen? You might be surprised if you use [Ethan’s] Python Sense Hat animation library. You can get the full visual effect in the video below.

The code uses an array to represent the screen, which isn’t a big deal since there are only 64 elements. Turning on a particular element to animate, say, a pong puck, isn’t hard with or without the library. Here’s some code to do it with the library:

for x in range(0,7):
 ect.cell(image,[0,x],[randint(0,255), randint(0,255), randint(0,255)],0.1)
 ect.cell(image,[0,x],e,0.1)
for x in range(7,0, -1):
 ect.cell(image,[0,x],[randint(0,255), randint(0,255), randint(0,255)],0.1)
 ect.cell(image,[0,x],e,0.1)

Each loop draws a box with a random color and then erases it before going to the next position. The second for loop makes the puck move in the opposite direction. You can probably deduce that the first argument is the screen array, the second is the position. The third argument sets the color, and the final argument sets an animation timer. Looking at the code, though, it does look like the timer blocks which is probably not going to work for some applications.

If that’s all there was, this wouldn’t be worth too much, but you can also draw triangles, circles, and squares. For example:

ect.circle(image,(4,4), 3, [randint(0,255), randint(0,255), randint(0,255)], 0.1)

We covered the Sense Hat awhile back. Of course, it does a lot more than just light up LEDs as you can see from this weather dashboard.

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