LEDs Turn This Paper Map into a Tram Tracker

Subway radar

Public transit can be a wonderful thing. It can also be annoying if the trains are running behind schedule. These days, many public transit systems are connected to the Internet. This means you can check if your train will be on time at any moment using a computer or smart phone. [Christoph] wanted to take this concept one step further for the Devlol hackerspace is Linz, Austria, so he built himself an electronic tracking system (Google translate).

[Christoph] started with a printed paper map of the train system. This was placed inside what began as an ordinary picture frame. Then, [Christoph] strung together a series of BulletPixel2 LEDs in parallel. The BulletPixel2 LEDs are 8mm tri-color LEDs that also contain a small controller chip. This allows them to be controlled serially using just one wire. It’s similar to having an RGB LED strip, minus the actual strip. [Christoph] used 50 LEDs when all was said and done. The LEDs were mounted into the photo frame along the three main train lines; red, green, and blue. The color of the LED obviously corresponds to the color of the train line.

The train location data is pulled from the Internet using a Raspberry Pi. The information must be pulled constantly in order to keep the map accurate and up to date. The Raspberry Pi then communicates with an Arduino Uno, which is used to actually control the string of LEDs. The electronics can all be hidden behind the photo frame, out of sight. The final product is a slick “radar” for the local train system.

City Lights Telling Stories

morse code lights

If you’re walking around town and you see a light suddenly start to switch on and off seemingly at random, don’t discount it as a loose wire so quickly. [René] has been hard at work on a project to use city lights of all shapes and sizes for Morse messages, and a way for anyone to easily decode these messages if they happen upon one while out and about.

The lights can tell any story that is programmed into them. The code on the site is written for an Arduino-style microcontroller but it could be easily exported to any device that can switch power to turn a light on and off. Any light can work, there’s even video of a single headlight on a van blinking out some dots and dashes.

The other part of this project is a smartphone app that can decode the messages using the camera, although any Morse code interpreter can translate the messages, or if you’re a ham radio enthusiast you might recognize the messages without any tools whatsoever!

The great thing about this project is that it uses everyday objects to hide messages in plain sight, but where only some will be able to find them. This is indeed true hacker fashion! If you’re interested in making your own Morse code light, the code is available on the project site.

The Walking Dead Survival Box for the Zombie Apocalypse 


When the world comes to an end and zombies run through the streets like a blood thirsty disease, it will be absolutely necessary to store a weapon (or five) away just in case an undead creature tries to get inside. In addition, stopping crooks from ransacking back up supplies will also be a primary concern as well as savage, brain-eating beasts take over the cities. Keeping objects safe with a lock box like this one would deter both undead creatures and mischievous thieves. Or at least that is what was going on in [Mattt Reamer's] head when he took on this build.

[Matt] is a UX designer who drew inspiration from the wildly popular television series The Walking Dead. He even 3D printed the Walking Dead’s logo on the front of the blood stained box attributing the idea to the show.

The setup here uses an Arduino Uno which is powered by a 9-Volt battery. The fingerprint scanner unlocks the box by verifying the print against a reverence copy stored in the code. When the program authorizes the scan, a servo opens up the latch allowing the contents within to be retrieved. Video of the full system can be seen after the break.

Now all that comes next would be to protect those fingers.

[Read more...]

Mood Lighting with LEDs and an Arduino

arduino ir candle

Regular candles can be awfully boring at times. They can only produce one color and the flicker is so… predictable. They can’t even be controlled by an infrared remote control, not to mention the obvious fire hazard. Now, however, [Jose] has come up with an LED candle that solves all of these problems. (Original link to the project in Spanish.)

The heart of the project is an Arduino Pro Mini, which is especially suited for this project because of its size. [Jose] put the small form-factor microcontroller in the base of a homemade wax enclosure and wired it to a Neopixel WS2812b LED strip. The strip can produce any color, and has some programmed patterns including flicker, fade, rainbow, and fire.

The artificial candle is controlled with an infrared remote control, and all of the code for the project is available on the project site if you want to build your own. [Jose] has been featured here before for his innovative Arduino-driven RGB lighting projects, and this is another great project which builds on that theme!



End Table Kegerator Hides the Tap when You’re Not Looking


What’s better than an ordinary end table? How about an end table that can serve you beer? [Sam] had this exact idea and used his skills to make it a reality. The first step of the build was to acquire an end table that was big enough to hold all of the components for a functional kegerator. This proved to be a bit tricky, but [Sam] got lucky and scored a proper end table from a garage sale for only $5.00.

Next, [Sam] used bathroom sealant to seal up all of the cracks in the end table. This step is important to keep the inside cold. Good insulation will keep the beer colder, while using less electricity. Next, a hole was cut into the top of the table for the draft tower.

The draft tower is mounted to a couple of drawer slides. This allows the tower to raise up and down, keeping it out of sight when you don’t want it. The tower raises and lowers using a simple pulley system. A thin, high strength rope is attached to the tower. The other end is attached to a spool and a small motor. The motor can wind or unwind the spool in order to raise and lower the tower.

The table houses an Arduino, which controls the motor via a homemade H bridge. The Arduino is hooked up to a temperature sensor and a small LCD screen. This way, the users can see how cold their beer will be before they drink it.

To actually keep the beer cold, [Sam] ripped apart a mini fridge. He moved the compressor and condenser coils to the new table. He had to bend the coils to fit, taking care not to kink them. Finally he threw in the small keg, co2 tank and regulator. The final product is a livingroom gem that provides beer on demand.

Demo video (which is going the wrong way) can be found after the break.

[Read more...]

Environmental Sound Detectors 

noise monitor 2.4noise monitor 3.41

We all know that sound. That sound of a noisy yapping dog, or the sound of a disruptive garbage truck loudly picking up the trash while making a ruckus along the way. It can be extremely distracting and frustrating to deal with. And more often than not, we have little control over the noise pollution in the area. Unless of course, you build a monitoring solution to raise awareness of the situation, like this one that [Edmund] made.

It was designed in conjunction with the Earth Journalism Network (EJN) in order to, as their website states, “facilitate story-telling of the sources and health impacts of noise from around the world“. An Arduino Pro Mini was the backbone of the project. Being open-source in nature meant that it could be customized easily with a wide array of sensors. [Edmund] chose to use an Electric Imp adding WiFi capability to the device. His step-by-step tutorial showed the design process, leading into the prototyping of the parts, and contains schematics for the circuit. As of the time that this article was published, the coding section of project hasn’t been released yet, but the first three parts give enough information to get the ball rolling.

This type of monitoring solution has the potential to record the noise levels of neighborhoods all across the world. With a large enough pool of data, API’s can be developed for uses like house hunting web searches that show which areas in town are the quietest, or which ones are the loudest. This will surely provide a wealth of knowledge about noise pollution, and it will be interesting to see how people utilize this (and projects similar) in the future.

Arduino Powered Digital Kaleidoscope


[Jose's] latest project brings an old visual effect toy up to date with digital electronics. Most of us are familiar with inexpensive kaleidoscope toys. Some of us have even built cheap versions of them with paper tubes, mirrors, and beads. [Jose] wanted to try to recreate the colorful pattern effects created by a kaleidoscope using an Arduino and an addressable LED strip.

The build is actually pretty simple. The base is a disc of PVC cut to just a few inches in diameter. [Jose] started with an addressable LED strip containing 60 LEDs. He then cut it into 12 sections, each containing five LEDs. The smaller strips were then mounted to the disc, similar to spokes on a bicycle wheel. The LED strip already has an adhesive backing, so that part was trivial.

The final step was to add some kind of diffuser screen. The LED strips on their own are not all that interesting. The diffuser allows the light to blend together, forming interesting patterns that are more reminiscent of the patterns you might see in a real kaleidoscope. Without the diffuser you would just see individual points of light, rather than blended color patterns.

The whole thing is controlled by a small Arduino. [Jose] has made the code available at the bottom of his blog post. Be sure to watch the video of the system in action below. [Read more...]


Get every new post delivered to your Inbox.

Join 94,571 other followers