Upgrading An Old Lantern

[Shockwaver] stumbled across some old kerosene lanterns, and decided he also stumbled across his next project. He decided to leave the kerosene out, and in its place used some RGB LEDs to bring the lanterns back to life. This is quite an upgrade. Considering the burning kerosene will only put out a few colors of light, the astute reader will have realized the RGB array has the ability put out over 16 million colors.

After some initial testing, he settled on a 24 LED circle array powered by an ATtiny85. The FastLED library helped him keep the code within the tight memory requirements. [Shockwaver] was not used to working with the such a small amount of memory, but after some fiddling he was able to make it work in the end, using 8,126 bytes.

The source can be found on his github page. Be sure to check out the video below to see the RGB lantern in action.

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Polar Coordinate Mapping And RGB LED Disks

Last week, Adafruit released the DotStar RGB LED Disk, a 240mm diameter disk packed with 255 individually addressable RGB LEDs. Because blinkey glowey projects are the best projects, [Adam] had to have one. His tests open up some interesting possibilities in the world of blinkey LED stuff, including a polar coordinate display that would be perfect for low-res games and LED clocks.

[Adam] found the Disk sufficiently bright and glowey, but there were two problems. The first was the JST SM connector on the input of the DotStar Disk; with 255 LEDs on the disk, it has a maximum draw of over 10A, while the connector can only supply 7A without getting unreasonably warm. Secondly, there aren’t 60 LEDs around the outer edge of the disk, limiting its application as a clock.

There’s another thing wrong with the DotStar Disk, until you realize it’s effectively a polar coordinate display. RGB LED libraries are usually written for strips or matrices, not circles. The LEDs are sequentially arranged on the DotStar disk spiraling inwards, and after mucking about with some terrible code, [Adam] realized he could control a pixel with only its distance from center and angle from the connector. This makes plotting circles easier, but it also opens this display up to some interesting applications; circular Pong would be cool, and LED clocks are the bees knees.

3D Printed Headgear Turns You into a Sim

Stop what you’re doing and dust off that 3D Printer, you’re going to want this headgear for your next party. [Daniel Harari] has created the perfect start of a phenomenal The Sims costume with this Bluetooth-enabled plumb bob.

The iconic crystalline shape will be familiar to anyone ever exposed to the game. It served as a handle and indicator for each virtual character in the popular life-simulation video game. On a short build deadline (a party), [Daniel] found a model of the shape he wanted on Thingiverse. He printed it in translucent green PLA so that LEDs inside would make it glow.

A headband and an aluminum pipe connect this to the wearer. Inside the printed enclosure is a an intricately packaged set of electronics that include an Arduino pro mini, low-side transistors to control six RGB LEDs, and an HC-05 Bluetooth module to connect to his phone. Batteries were mounted on the side of the pipe but we bet a bit of head scratching could re-imaging the battery type and get it inside the enclosure as well.

[Daniel] muses about adding brainwave sensing to control the LEDs. For this build he didn’t even need to write an app; he was able to get an already available color-picker to work. We’d like to see this combined with sentiment; a concept starting to gain popularity which samples social media and ascertains mood to change the display base what is found.

You realize what’s missing from his writeup? We couldn’t find any pictures of him wearing the thing!

Documenting Poorly Documented LED Strips

While [Drew] was in China for the Dangerous Prototypes Hacker Camp, he picked up some very bright, very shiny, and very cheap LED strips. They’re 5 meter “5050” 12V strips with 20 LEDs per meter for about $15 a spool. A good deal, you might think until you look at the datasheet for the controller. If you want an example of how not to document something, this is it.

A normal person would balk at the documentation, whereas [Drew] decided to play around with these strips. He figured out how to control them, and his efforts will surely help hundreds in search of bright, shiny, glowy things.

You are expected to tell the difference between 'GMODE', 'OMODE' and 'CMODE' in this pinout.
You are expected to tell the difference between ‘GMODE’, ‘OMODE’ and ‘CMODE’ in this pinout.

The datasheet for the LPD6803 controller in this strip – available from Adafruit here – is hilarious. The chip takes in clocked data in the order of Green, Red, and Blue. If anyone can explain why it’s not RGB, please do so. Choice phrasing includes, “VOUT is saturation voltage of the output polar to the grand” and “it is important to which later chip built-in PLL regernate circuit can work in gear.” Apparently the word ‘color’ means ‘gray’ in whatever dialect this datasheet was translated into.

Despite this Hackaday-quality grammar, [Drew] somehow figured out how to control this LED strip. He ended up driving it with an LPC1768 Mbed microcontroller and made a demo program with a few simple animations. You can see a video of that below.

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A Hacker-Friendly Blinky USB Stick

The availability of Smart RGB LED’s, either as individual units, as strips or even as panels, have made blinky light projects with all kinds of color control and transition effects easy to implement using even the simplest of controllers. Libraries that allow control of these smart LEDs (or Smart Pixels as they are sometimes called)  make software development relatively easy.

[overflo] at the Metalab hackerspace in Vienna, Austria recently completed development of usblinky – a hacker friendly blinky USB stick. It can control up to 150 WS2812B smart LED’s when powered via an external power supply, or up to 20 LED’s when powered via a computer USB port. The micro-controller is an ATTiny85 running the Micronucleus bootloader which implements software USB using vUSB. The hardware is based on the DigiSpark platform. The usblinky software sources are available on their Github repo. The section on pitfalls and lessons learned makes for interesting reading.

Metalab plans to run workshops around this little device to get kids into programming, as it is easy enough and gives quick visual feedback to get you started. To round off the whole project, [overflo] used OpenSCAD to design a customizable, 3D printable “parametric orb” which can house the LED strip and make a nice enclosure or psychedelic night light. Check out the mesmerizing video of the usblinky Orb after the break.

Thanks to [papst] for sending in this tip.

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Mapping WiFi Signals in 3 Dimensions

[Charles] is on a quest to complete ever more jaw-dropping hacks with the popular low-cost ESP8266 WiFi modules. This week’s project is plotting WiFi received signal strength in 3D space. While the ESP8266 is capable of providing a Received Signal Strength Indication (RSSI), [Charles] didn’t directly use it. He wrote a simple C program on his laptop to ping the ESP8266 at around 500Hz. The laptop would then translate the RSSI from the ping replies to a color value, which it would then send to the ESP8266. Since the ESP8266 was running [Charles’] custom firmware (as seen in his WiFi cup project), it could directly display the color on a WS2812 RGB LED.

The colors seemed random at first, but [Charles] noticed that there was a pattern. He just needed a way to visualize the LED over time. A single frame long exposure would work, but so would video. [Charles] went the video route, creating SuperLongExposure, an FFMPEG-based tool which extracts every video frame and composites them into a single frame. What he saw was pretty cool – there were definite stripes of good and bad signal.

wifiPOVThumbArmed with this information, [Charles] went for broke and mounted his ESP8266 on a large gantry style mill. He took several long exposure videos of a 360x360x180mm area. The videos were extracted into layers. The whole data set could then be visualized with Voxeltastic, [Charles’] own HTML5/WEBGL based render engine. The results were nothing short of amazing. The signal strength increases and decreases in nodes and anti-nodes which correspond to the 12.4 cm wavelength of a WiFi signal. The final render looks incredibly organic, which isn’t completely surprising. We’ve seen the same kind of image from commercial antenna simulation characterization systems.

Once again [Charles] has blown us away, we can’t wait to see what he does next!

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Hackaday Links: February 1, 2015

It’s Sunday evening, and that means Hackaday Links, and that means something crowdfunded. This week it’s UberBlox. It’s a modular construction system based on Al extrusion – basically a modern version of an Erector set. Random musings on the perceived value UberBlox offers in the comments, I’m sure.

[Trevor] sent in something from his Etsy shop. Normally we’d shy away from blatant self-promotion, but this is pretty cool. It’s reproductions of 1960s Lockheed flying saucer plans. We’re not sure if this is nazi moon base/lizard people from the inner earth flying saucer plans or something a little more realistic, but there you go.

3D computer mice exist, as do quadcopters. Here’s the combination. It looks like there’s a good amount of control, and could be used for some aerobatics if you’re cool enough.

Who doesn’t love LED cubes? They’re awesome, but usually limited to one color. Here’s an RGB LED cube. It’s only 4x4x4, but there’s a few animations and a microphone with a beat detection circuit all powered by an ATMega32u4.

A while ago we had a post about a solar powered time lapse rig. Time lapse movies take a while, and the results are finally in.