Great Scott! A Flux Capacitor Notification Light

February 17, 2015 by Rick Osgood 9 Comments

If you are into your social media, then you probably like to stay updated with your notifications. [Gamaral] feels this way but he wasn’t happy with the standard way of checking the website or waiting for his phone to alert him. He wanted something a little more flashy. Something like a flux capacitor notification light. This device won’t send his messages back in time, but it does look cool.

He started with an off-the-shelf flux capacitor USB charger. Normally this device just looks cool when charging your USB devices. [Gamaral] wanted to give himself more control of it. He started by opening up the case and replacing a single surface mount resistor. The replacement component is actually a 3.3V regulator that happens to be a similar form factor as the original resistor. This regulator can now provide steady power to the device itself, as well as a ESP8266 module.

The ESP8266 module has built-in WiFi capabilities for a low price. The board itself is also quite small, making it suitable for this project. [Gamaral] used just two GPIO pins. The first one toggles the flux circuit on and off, and the second keeps track of the current state of the circuit. To actually trigger the change, [gamaral] just connects to the module via TCP and issues a “TIME CIRCUIT ON/OFF” command. The simplicity makes the unit more versatile because an application running on a PC can actually track various social media and flash the unit accordingly.

Mapping WiFi Signals In 3 Dimensions

February 17, 2015 by Adam Fabio 58 Comments

[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.

Armed 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!

Continue reading “Mapping WiFi Signals In 3 Dimensions” →

Animated LED Valentine Heart

February 13, 2015 by Rick Osgood 3 Comments

With only a week left until Valentine’s day, [Henry] needed to think on his feet. He wanted to build something for his girlfriend but with limited time, he needed to work with what he had available. After scrounging up some parts and a bit of CAD work, he ended up with a nice animated LED Valentine heart.

[Henry] had a bunch of WS2812 LEDs left over from an older project. These surface mount LED’s are very cool. They come in a small form factor and include red, green, and blue LEDs all in a single package. On top of that, they have a built-in control circuit which makes each LED individually addressable. It’s similar to the LED strips we’ve seen in the past, only now the control circuit is built right into the LED.

Starting with the LEDs, [Henry] decided to build a large animated heart. Being a stickler for details, he worked out the perfect LED placement by beginning his design with three concentric heart shapes. The hearts were plotted in Excel and were then scaled until he ended up with something he liked. This final design showed where to place each LED.

The next step was to design the PCB in Altium Designer. [Henry’s] design is two-sided with large copper planes on either side. He opted to make good use of the extra copper surface by etching a custom design into the back with his girlfriend’s name. He included a space for the ATMega48 chip which would be running the animations. Finally, he sent the design off to a fab house and managed to get it back 48 hours later.

After soldering all of the components in place, [Henry] programmed up a few animations for the LEDs. He also built a custom frame to house the PCB. The frame includes a white screen that diffuses and softens the light from the LEDs. The final product looks great and is sure to win any geek’s heart. Continue reading “Animated LED Valentine Heart” →

Slick Bathroom Mirror Is All Tricked Out

February 12, 2015 by Anool Mahidharia 6 Comments

A Mirror surrounded by a string of brightly lit lamps is something you usually get to see in a Movie Star’s dressing room. [pickandplace] was inspired by the Movies, and a dark bathroom, to come up with a Bathroom Mirror equipped with some bells and whistles. To start with, his planning was quite detailed, sketching out the features and constraints for his design. He chose to use a round mirror with 12 LED bulbs (which are safer than 220V bulbs) so it can work as a clock. User input is handled by a motion sensor to automatically switch it on/off and a capacitive touch dimmer. Under the hood there’s an RTC (for clock and brightness adjustment based on time of day), simple boost PWM LED driver, thermal management for the LEDs which are 10W, temperature sensor to pipe down the current if the LEDs get too hot, and even an anti-fogging heater strip – phew!

His execution is no less brilliant. Starting with building the wooden frame and ending with the code for driving all the electronics. Along the way, you will find detailed notes on the LED’s, PWM Driver, Heat sinking, and capacitive Touch dimmer using Atmel’s AT42QT2160 Qslide – Matrix Sensor IC. He had some trouble with the Motion Sensor PIR module, and hasn’t yet written the code to implement it. His first version used a PIC18F87J50, and the next iteration had an ATXmega256A3BU – but he asks us not to get into the Microchip vs. Amtel debate. We have to agree on that. Sharp readers will point out that neither of the two micro’s can provide 12 PWM channels. Well, worry not, he has it all figured out. He also coded up a simple control interface which is handy when the unit is hooked up over USB to a computer. To top it off, he built a miniature LED ring to use as a “Simulator” while working on the code so he didn’t have to lug the heavy Mirror in and out of the bathroom. How’s that for doing a good job better! Source files are on his Github repo, and links to the hardware schematics are peppered throughout his blog.

If you don’t want to build something so fancy, look up the Bathroom Mirror with HUD which displays Time and Weather

Continue reading “Slick Bathroom Mirror Is All Tricked Out” →

Display Your City’s Emotional State With Illuminated Snow

February 5, 2015 by Rick Osgood 8 Comments

[Hunter] wanted to do something a bit more interesting for his holiday lights display last year. Rather than just animated lights, he wanted something that was driven by data. In this case, his display was based on the mood of people in his city. We’ve seen a very similar project in the past, but this one has a few notable differences.

The display runs off of an Arduino. [Hunter] is using an Ethernet shield to connect the Arduino to the Internet. It then monitors all of the latest tweets from users within a 15 mile radius of his area. The tweets are then forwarded to the Alchemy Sentiment API for analysis. The API uses various algorithms and detection methods to identify the overall sentiment within a body of text. [Hunter] is using it to determine the general mood indicated by the text of a given tweet.

Next [Hunter] needed a way to somehow display this information. He opted to use an LED strip. Since the range of sentiments is rather small, [Hunter] didn’t want to display the overall average sentiment. This value doesn’t change much over short periods of time, so it’s not very interesting to see. Instead, he plots the change made since the last sample. This results in a more obvious change to the LED display.

Another interesting thing to note about this project is that [Hunter] is using the snow in his yard to diffuse the light from the LEDs. He’s actually buried the strip under a layer of snow. This has the result of hiding the electronics, but blurring the light enough so you can’t see the individual LEDs. The effect is rather nice, and it’s something different to add to your holiday lights display. Be sure to check out the video below for a demonstration. Continue reading “Display Your City’s Emotional State With Illuminated Snow” →

Super Bowl Football Lamp Keeps You Informed

February 4, 2015 by Rick Osgood 7 Comments

[David] loves to watch football. After his preferred team lost the playoffs, he wanted another reason to watch the big game last Sunday. He ended up building himself a football-shaped lamp that changes color based on who scored last.

[David] started with a Spark Core and a Spark Button. The Spark is the primary microcontroller and includes WiFi. The Spark Button is essentially a shield for the Spark that includes an accelerometer, some LEDs, and a few push buttons. The other part of this build was the housing. [David] used a toy football he got for free as swag from a parade.

As for the code, [David] started by first learning how to control the LEDs on the Spark Button. Then he wrote his own touchdown function to illuminate the football a specific color. Since the Spark uses the REST API, [David] is able to trigger this function by simply visiting the URL of his Spark. This makes it very simple to trigger the event.

The final part of this build was made easy thanks to IfThisThenThat (IFTTT). This is a web service that allows you to monitor and interact with various online web services. It can monitor one service, and then interact with another based on events that happen in the first service. In this case, [David] is using a “channel” added to IFTTT by ESPN. This channel can trigger when certain events happen for whatever team you specify. For this project [David] is monitoring touchdowns.

After combining all of these various services, [David] had a working light that would change colors based on which team scored. He did notice that IFTTT has anywhere between a 1 and 15 minute delay, and he hopes to improve upon this design by hooking directly to an API and skipping the extra service altogether.

Hacklet 32 – LED Persistence Of Vision Displays

January 30, 2015 by Adam Fabio 7 Comments

Blinking LEDs are good. Moving, spinning things are good too. Put them both together and you get a Persistence of Vision (POV) display. Hackers have been building these displays for years. This week’s Hacklet focuses on some of the best LED POV displays on Hackaday.io!

We start with [EduardoZola] and POV as you type, write on the air. [Eduardo] used an Arduino Nano, a pair of 433 MHz radios, some blue LEDs and a motor to create a simple spinning display. A hall effect sensor keeps everything in sync. The entire display is powered by a 500 mAh LiPo battery. The awesome thing about this display is the interactive aspect. The transmitter module connects to a laptop via an on-board USB to serial converter. Typing into any serial terminal sends the text directly to the POV display, where the letters appear to hang in the air.

Next up is [boolean] with Silent Orchestra POV aka “Death Ring”. [boolean] didn’t want to just create a POV ring, he wanted a huge 5 foot diameter display for his local Burning Man decompression. Death Ring is an aluminum ring spun by a 3HP motor. A hall effect sensor keeps everything synced up, and keeps Death Ring’s 3 horsepower motor in check. Light is provided by a PixelPusher and WS2812 RGB strips. The system is designed to be interactive, controlled with a Leap Motion controller or a Microsoft Kinect. An MPU-6050 keeps acceleration in check while processing maps video to the LED strip. An Arduino Yun allows the entire system to be controlled via WiFi. [boolean] and his team have taken Death Ring through several revisions. Judging by the quality of their aluminum welding though, they’re on the right track to an awesome end result!

Hackaday.io power user [Davedarko] has been working on a POV display of a different sort. His Locomatrix is an 8×8 LED matrix which moves in and out on the Z axis. [Dave] originally created Locomatrix as his entry in the 2014 Hackaday Prize. We have to admit this is the first time we’ve seen this sort of display, but the idea is sound. In fact, [Bruce Land] posted in the comments to let [Dave] know that he’d seen a similar technique used with a CRT display back in 1964. We’re betting Dave’s 3D printed gears and LED matrix display will be more robust than a CRT tube slamming two and fro at several hundred pulses per minute!

Finally, we have Hackaday’s own [Mike Szczys] with CPOV – a Crappy Persistence of Vision display . CPOV is a proof of concept made from upcycled parts which [Mike] threw together in a couple of hours. He grabbed the motor from an old cassette deck, some plywood, perfboard, and of course LEDs to build his display. The processor is an ATtiny2313 running Adafruit’s MiniPOV 3 firmware. The system display doesn’t have a sync input, so [Mike] uses a novel form of Human-in-the-loop PWM control to keep the motor speed in check. CPOV is proof that Hackaday.io isn’t just for polished projects, but for proof of concepts, fails, and just plain research. Even if your project isn’t perfect, documenting it will help you learn from it. It might even inspire someone else to move forward and continue where you left off!

Want more POV goodness? Check out our new POV display list!

Our LEDs are going dim, so that’s about all the time we have for this Hacklet. As always, see you next week. Same hack time, same hack channel, bringing you the best of Hackaday.io!