Becoming The YouTube Loading Animation

March 12, 2012 by Brian Benchoff 75 Comments

Whether you’re used to dropped wifi connections, or your housemates are using up all the bandwidth for streaming, we’ve all see the spinning octet of disks that is the YouTube loading animation. [technocrat] thought it would be a great idea to actually become YouTube and set out on designing a physical manifestation of the loading animation.

[technocrat] used eight ping-pong balls as the main structure of the build. After drilling each ping-pong ball and gluing white LEDs in, the only thing left was to connect everything up to an Arduino. The code loops through each LED and provides the ‘light trail’ animation YouTube has burned into our memory.

To complete the build, [technocrat] attached his physical loading animation to a black t-shirt emblazoned with the YouTube logo to make everything more understandable. While it may not be as colorful as the beachball of death or as conceptual as the Windows ‘spinning hourglass’, we’re really liking this build. Check out the video after the break.

Continue reading “Becoming The YouTube Loading Animation” →

LED Tutorial Demystifies Several Control Techniques

March 8, 2012 by Mike Szczys 31 Comments

Controlling LEDs is really quite simple. As you know, they need to be current limited which is as easy as applying Ohm’s law to your given set of values. To make things even more even there’s a slew of constant current LED driver chips out there that can be had for a song. But do you have any idea how those constant current circuits work? If not, then [Giorgos Lazaridis’] guide on LED driving and controlling methods will bring you up to speed in no time.

He starts out with the most basic concept, how to light an LED using proper current limiting resistors. But from there he moves on to the juicy bits. He builds a transistor-based constant current driver, then adds voltage regulation for the circuit as seen in the schematic on the left. He moves on to the more robust and efficient method on the right which pairs a MOSFET with that transistor circuit. This is the technique found on each pin of many of those constant current drivers and functions well regardless of the voltage input level.

He’s been producing videos to go along with these articles. After the break you can watch the episode that accompanies the schematic on the left. Continue reading “LED Tutorial Demystifies Several Control Techniques” →

Adding A Lot Of Twinkle To This Rebar Sculpture

March 7, 2012 by Mike Szczys 11 Comments

Blinky lights have a way of attracting attention and that’s exactly what the members of the Maui Makers hackerspace were shooting for. The sculpture above is the logo for the Source festival, a Burning Man inspired music gathering in the Aloha state. For this year’s festival they went crazy, installing twelve meters of RGB LED strip controlled by seven Arduino boards.

The goal was to make the twelve-foot tall sculpture into a lighted interactive showpiece. In addition to the LEDs it includes a microphone, capacitance sensors, Bluetooth connectivity, and a piezo speaker. There’s one Arduino to rule them all, with another Teensy controller to drive an LCD display in the control box, and five Teensy boards to address the LED strips. They grabbed [Bill Porter’s] Easy Transfer library to facilitate communication between the microcontrollers (his libraries are becoming popular, we just saw his mp3 shield library used in another project on Tuesday).

The code which drives the LED animations is based on some Adafruit examples. We really enjoy the waving flag effect seen in the clip after the break.

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Simple Hardware And Python Drive This Splunk LED Meter

March 2, 2012 by Mike Szczys 2 Comments

Want to monitor the company system without continually loading up the Splunk dashboard? It turns out that they’ve got their own Python package which makes pulling down data a snap. All [Rick] needed to do was hook up an LED meter as an external display.

It used to be that this would take a lot of wire and bit of soldering (or some special Christmas lights), but the advent of affordable LED strips has really taken the guess-work out of it. He’s using an RGB version acquired from Adafruit Industries. These strips are driven using SPI and multiple-colors mean you can display multi-dimensional data using one column. He chose to use a Teensy microcontroller, grabbing some plastic packaging for welding rods as the enclosure. These strips are extremely bright and to help soften the impact he added wax paper to the inside of the enclosure to act as a diffuser.

Looking for more projects that use strips like this one? They make fantastic addressable accent lighting for your home.

Wind-powered POV Weather Station

March 2, 2012 by Mike Szczys 23 Comments

The more we think about this one the more we like it. [Michael] built himself a wind-powered persistence-of-vision weather station. Okay, that sounds interesting, but he ups the ante when you find out what’s included in the system.

A stepper motor acts as the generator which powers the electronics. As we’ve seen before; if you spin the shaft of a stepper motor electricity is produced. [Michael] is actually spinning the housing of the motor, with the shaft mounted to the base that holds the weather station in place. This way, the electrical contacts are spinning along with the blades of the generator. By mounting all of the electronics on these blades he gets around the problem of transferring power onto a spinning platform.

A set of LEDs on the end of the blades display temperature and relative humidity readings. A hall effect sensor pulled form an old floppy drive syncs the display with the rotational speed. He’s even got a shunt system which keeps the input voltage at a safe level, and will act as a break in high winds to keep the rotors from spinning out of control. See what we mean? An interesting idea because a fantastic project when you build in features like these!

Doubling Up On The USB Supercap Flashlight

February 28, 2012 by Mike Szczys 28 Comments

[Antoine] wrote in to let us know that he soldiers on with his flashlight project. He’s doubled up on the supercaps and tripled the LEDs (translated).

The core concept has stayed the same since the original version. He wanted a flashlight that was small and used no batteries. This iteration came about as he looked at increasing the light output of the device. He’s switched to some warm-white LEDs which are easier on the eyes, but was unhappy with the charge life now that he’s using current at a faster rate. The solution, of course, is more potential from the capacitor. He’s now using two 10 Farad caps in parallel. We are a little skeptical about his capacitor theory and ended up using this lecture to defog the issue of parallel and series capacitance.

The upgraded hardware is right at home in that plastic egg like you’d find in a coin-op trinket vending machine. You’ll see there’s still a colored LED to warn when the charge is getting too low.

Light Painting With A String Plotter

February 27, 2012 by Mike Szczys 12 Comments

[Matt Bell] sends a shout-out to Hackaday by creating a light-painting of our logo with his string plotter. He starts off by setting up a pair of stepper motors which each have a spool to wind and unwind a string. The plotter is made by suspending a stylus between these two strings. In this case, he’s using a wireless LED board (seen above) built from the remote control receiver/transmitter from a toy car. The link above is part of a Flickr set from which you can get the whole story by reading the captions of each image.

After the break we’ve embedded a clip of an in-progress light painting. You can see there’s some oscillation of the LED unit that makes it a bit less precise than the CNC light painter we saw a couple of weeks ago. It seems like string plotters usually don’t have this issue if the stylus has something to help stabilize it. We wonder if a piece of acrylic would help get rid of the shakes? Continue reading “Light Painting With A String Plotter” →