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Easter Egg Hunt Rules, 2014.

We love doing Easter egg hunts.  But as the girls get faster, smarter, and more wily, merely finding the eggs is no longer challenge enough.  I’ve gotta slow ’em down somehow, and this is how I do it: each girl gets an empty basket (I use traditional Jack-O-Lantern baskets), and sheet of instructions helping her know which eggs are for her, and which are for her step-sister.  Each year, the instructions require more careful reading and invoke increasingly complicated rules.

New this year: the contents of two of the eggs altered the interpretation of rules, retroactively. This fact itself was part of the published rules… this time.

 


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The best part was watching the girls excitedly pounce as they found the first eggs, and then stall completely as they had to stop and puzzle out exactly who’s egg it actually was that they’d just found.

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-Mark

 


 

P.S. Here are the previous year’s Egg Hunt Rules (2013):

Easter2013

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Fire2012: an open source fire simulation for Arduino and LEDs

I’ve built and programmed a couple of different ‘fire’ simulations for Arduino and LEDs, and I’ve had numerous requests over the years to share the source code.  I’ve always been happy to share my work; the holdup has been that before I share my code for the world to peer at, I like to clean it up a little.  I like to give the code a clean shave and scrub under its fingernails before it steps out onto the wide open Internet where it might have an audience with Her Royal Majesty, The Queen of England.  It could happen.

Anyway, I finally cleaned up the code for one of my simplest and most legible ‘fire’ simulations, and I give it to you, your Majesty, and everyone else, too. Here’s a video of the code in action on a 30-pixel strip of WS2812B LEDs (or maybe WS2811) and an Arduino.  Source code link is below the video.

Full source code is here: http://pastebin.com/xYEpxqgq  The simulation itself is only about 25 or 30 lines of code.  It uses our (open source) FastLED library to drive the LEDs.

Discussion about the code and how to port it and use it are here on the FastLED discussion group on G+ https://plus.google.com/112916219338292742137/posts/BZhXE4cqEN4

Enjoy!

-Mark

 


If I’m confused, it must be playtime.

Some things we try because we have a clear idea where we want to be and a clear idea how to get there.

Some things we try because we’re suddenly shocked to find that the heretofore completely impossible has suddenly and surprisingly come within practical reach.

And some things we try just to play, and to explore what if. We start with our heads full of simple ideas that turn out to be wrong, and we awkwardly replace them in torn out bunches with new confused half-understandings that, later, will let us reach something wholly unexpected.

I’m not sure which of these things in doing here, which means it’s probably that last one.

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Running 2 Amps of LEDs through an Arduino Nano

The Arduino Nano provides up to 0.5 Amps of regulated +5v output, on it’s “+5V” pin, which can drive between 10-30 addressable LEDs, depending on your chosen brightness and animation patterns.  Even if you connect a 2 Amp USB power supply (e.g. an iPad charger), the Nano’s little voltage regulator will overheat if you try to draw more than 0.5 Amps from the “+5V” pin on the Arduino.

However, you can ‘tap’ the pre-voltage-regulator power traces on the Nano’s circuit board, and drive 2 Amps of LEDs (over 100) ‘through’ the Nano, and do it in a way that keeps your wiring simple.  Basically, you can find the places on the Nano’s board where the raw USB power connections are exposed, and tap into them there.

WARNING!  
MODIFY, MISUSE, AND DESTROY YOUR ARDUINO AT YOUR OWN RISK!
DANGER! FIRE! RUN! 

But, OK, if you wish to continue…

1. Flip the Nano over so you’re looking at the bottom side.

Two Amp Arduino Nano

2. The unfiltered, unregulated +5 signal from the USB port is available on the board near the base of the D2 pin.  Carefully solder a wire (red, for +5v) directly to the exposed component pin on the circuit board.

3. A convenient companion GND connection can found on the center pin of the power regulator itself.  Solder a wire (black, for ground) to this pin.

4. By powering your LEDs from these direct-power traces (and thus directly from the USB power source), instead of through the Nano’s half-amp-max voltage regulator, you can drive up to about two Amps worth of LEDs, provided that you plug the Nano into a 2 Amp USB power adapter.

I’ve used this technique in probably six or eight Arduino Nano projects, and nothing’s caught fire (yet).  With a little probing around, you can also find similar ‘hacks’ for other models of Arduino, e.g., the Uno, Leonardo, etc., but since power is handled differently on each board, you’ll have to figure it out differently for each board design.

Good luck!


Hoop skirt — made with real hoops!

Eleanor and I spent this weekend working on her Halloween costume.  Part of what she planned was a ‘hoop skirt’, but as you can imagine no commercially available hoop skirt met her exacting standards of design and quality — and also my exacting budgetary requirements.  Naturally, we decided to take the DIY route!  And, we pondered, what goes into a hoop skirt? HOOPS, obviously!

We picked up a used dress at The Garment District (our local vintage/costume/cheapo clothing mecca), a set of three hula-hoops, and some leopard-print duct tape.  The smallest hula hoop became the bottom (largest) hoop for the skirt; the other two had to be dramatically resized smaller (via pliers, dremel, duct tape).  We started construction from the waist down, with a nylon web belt with a parachute snap buckle.  From there, we hung each hoop with repositionable blue painters tape, and balanced each one until it was level.  Then Eleanor secured each hoop in place at the right height with duct tape.

And presto! A hoop skirt made with real hoops! (and duct tape, of course!)

Hoop skirt -- made with real hoops!


“Firelight” Lantern

This past January (2013), I created “Firelight”, a lantern that shines with the light of a simulated fire.

The lantern contains over a hundred LEDs, a microcontroller, a battery pack, and custom software.  The software monitors the remaining power in the batteries, and as the voltage slowly runs down, the flames burn lower, finally dying into embers as the batteries die.

I presented the Firelight lantern at the Veracode winter Hackathon, where I lit it, and then gently blew on the coals to kindle a flame.  I’ve had a few requests to build more of these lanterns for other people, and I’m considering it, but haven’t made a decision yet.  More pictures are here.

-Mark

 

 


The Lightning Tree: Halloween

Over this past summer, I built “The Lightning Tree” — a 13-foot-tall steel and aluminum tree covered in hundreds of programmable LEDs.  Normally, The Lightning Tree slowly cycles through animations depicting the different seasons of the year, but for Halloween I reprogrammed it full of wild purples and oranges, and planted it in our front yard!

It attracted and delighted kids and grown-ups throughout Halloween night, but the time the sun rose, it had disappeared, like all things ephemeral and magic.  (To be clear: it disappeared in a good way, as Black Rock City does.)