Yup, Errol had lights before, but now...
Previously I wrote about using LED strips and I finally had a chance to try it. I used those Neopixel ones at 140+ LEDs per metre. (That's >700 LEDs for Errol's wings) I glued them along the side of plexiglass wing ribs and ground the other edge to a bevel so the light gets prismed off the edge. The effect is startling- the colours just transition along the entire wing rib and can strobe to a blinding level. Definitely something to try... (but, yeah, these wings are a little sturdier than my previous ones and I accidentally clobber someone every so often- embarrassing)
Anyway. The tech; that's something else. If any of you are going to try this, maybe my little journal entry here will help.
Of course, I immediately ran out of memory on the computer board I used (that Arduino YUN I have for the ESP section). It's fine without the 'Bridge' library, but I wanted that for the webserver. So, I'm still trying to come up with a way to rewrite that "Adafruit' library most people use for these strips (maybe you don't need 3 bytes of RAM per pixel). For now, the LEDs are limited to 260 per wing.
Also, these lights can use up to 3 amperes per wing so I quickly ran out of power. The voltage drop from the battery through the connectors and along the retractable cables to the wings was over 3 volts sometimes- enough so my batteries (which are 7 volts for the servos) didn't supply a high enough voltage. The computer would crash and the light show (though spectacular) wasn't what I planned.
So now I use a 12 volt battery and each part has a separate regulator to supply the 5 volts everything needs. (And these are 10 amp regulators) A pair of 3300 AH LiPOs seem to be doing the job.
One great thing of the Arduino are some nice demo programs for sound processing. Together with a microphone kit from Adafruit, my previous efforts at working with sound detection are terrible in comparison. WOW, this thing works well! I've fooled with the software a bit to make different display modes from spectrum to scrolling to strobe...
And now with that YUN board, it serves up a webpage with REST calls to the Arduino .ino sketch- you can do almost anything with the LEDs. How cool is that? 'Course, I'm still learning how to do this stuff too...

Dragons are supposed to be telepathic, right?
Well, I'm going to try an experiment for Vancoufur and Furnal this year. I've set Errol up with one of those Arduino YUN computer boards- theoretically anyone with a smartphone or tablet should be able to connect to Errol and once done, see the website Errol sends out. (Note that this is like a hotspot- you see 'Errol' like any other WIFI network) That website is connected to some of Errol's electronics...
Back at Howloween last year, I tried this with some success (I really had problems getting enough power to the wings) and hopefully can finesse the web page enough so anyone can understand it. Things like vote for the colour of the wings, the audio mode and make one of 3 vibrator motors (along Errol's shoulders) work.
I don't know... like the DS- maybe send a 'Hi Dragon'? A poke to get a dragon's attention? Vote for a move in the dance competition? Come up with a secret dragon code? Maybe help Errol demolish his opponent in Battleships? I'm looking forward to some more ideas and also happy to share any of this info to those interested. And I have been inspired in this project by a number of people, like Drake who's done something like this, and Keianza who was the one to go 'hey, I wonder...'
In the next journal I'll write a bit about the wing lights- whew, that was a challenge.

My soul and best friend, Tessa the german shepard, just joined me on a Xcountry ski trip... it was -20 degrees. Only after 2 hours did she lift a paw out of the snow in discomfort. And yet, at 30 above, she may pant but she's not really complaining much. How do they do it?
Airflow and liquid cooling, I'd think... and so should a fursuit. It's not easy having a clear path for a fan... ducts and grills aren't exactly something you want to see on a head. On the other hand, there's openings just right... the nose, the mouth, the ears- pretty much nature's cooling paths too. OK, and under the armpits and tail, but we won't talk about those.
Errol has 7 fans, two up the back, one at the tail, two in the snout, and two in the head. I really tried many types, because some NOIIIISY! The tail and snout fans are temperature controlled- 12 volt scroll type units from Memory Express. Since I use a 6 volt battery (for the servos) these fans need a step-up power supply. One of Errol's routines (Dance mode) bypasses the temperature control so they run all the time (but the dance floor is loud enough you don't hear the fans.
The rest of the fans run all the time. The back fans are laptop tray coolers from any Dollar store- very thin once you cut them out of the plastic of the cooler and run quietly from 6 volts (they're normally USB powered. Yes they will work at 12 volts but they're really power hungry and loud) I use a back-pack type of suspension to keep an airway open along my back (and they pull air in from the back ridges)
The head fans are 12 volt units, but I run them at 6 (but not every 12 volt fan will do that) They're pretty quiet and exhaust air out the top of the head.
I've picked up some liquid cooling parts and have heard people tried this- even heard people trying Peltier devices... would like to hear more about it. So far I've done better with the fans. And I really think the whole trick is getting a clear, low resistance pathway for air to flow. And if you had to pick one place for cooling, make it the snout- blow up past your face and forehead. The next best place is up the back... Ahhhhhhh.

For a change, let's make animals jealous... my dog sure loves anything glittering, dancing lights and laser spots. Ha. Nature has endowed very few creatures with lights.
Errol carries quite a few... about 60 or so. I wanted the lights to glitter in time to the sound nearby and in many colours and patterns. Errol hears sounds from his horns and his tail... the computers in each talk to one another and are supposed to decide which lights to illuminate. I needed the lights to compensate for the ambient brightness, so there's also light sensors in the head and tail. Well, its quite something to play with on the dance floor- I love watching the patterns of lights in the wings. I can't really see the others- the tail end, ridges and horns.
My biggest problem is the huge difference from loud to quiet! Something we can do so easily- crazy complex in hardware and computer code. Somehow you have to average out the levels and pick out the patterns. When the music is really loud, I'm just resigned to have the lights on continuous.
Most of the lights I use are off the shelf Xmas lights, Dollar Store fibre optic strands, Princess Auto EL wire kits and IKEA light strips. (ie, cheap) The cool thing is, with a little fooling around, they all can work from batteries and many types already have electronics that flash them or change the colours. A lot of these lights are absolutely tiny. OK, they do break rather a lot, so there's a lot of fixing...
But out there on the 'net are amazing multicoloured strips ready for computer communications (which I have seen in some Xmas light displays) Sadly, this goes beyond Errol's poor overcoded microcomputers.
EL wire is a bit more common these days, but power hungry, tough to cut to size and hard to control. I have a few of them in the wings.
And then the ultimate- fabrics with built in lights! (some with TV resolution) Drawback? Yup, expensive.
Ah, the fun I'm having!

Dragons need fire, right? To tell the truth, making fire would be quite easy to do, but I think it would be (strongly) discouraged by Con officials...
So the trick is to make something look like it. Smoke machines (quite a few sources on the 'net about these) use a glycerin/water mixture sprayed on a heater, and Errol uses the same idea... only smaller. An old microwave (food-ready sensor) provided the heater, but these can come from CO/gas detectors or E-cigarettes. Rather than spray the fluid, Errol uses an oil-lamp wick through the heater and a sealed reservoir (filled from a tube under the nose) for the fluid. A small fan directs the smoke out the nose. Small LED lights that flash give an 'inner-fire' effect.
To make Errol let off smoke, the tiny sensor from an E-cigarette is mounted near the base of the tongue- blow on it and a signal to the computer begins a timer for a relay that runs the heater. (these sensors also have a tiny light. Will run from 5 volts and provide a pull-down signal when blown on from the back side) About 1 ampere of current flows at 6 volts for the unit I did. The heater would get red hot, but the fluid cools it. The whole thing is mounted in a small box made of double-sided PC board material soldered together.
I have had zero success trying to make one of those fabric flames work... anyone try this?

An animal's yawn is truly amazing- how is it possible there can be so much movement with so much force... once you try to do something like this you too will shake your head in awe.
Errol uses the mouth position to help choose a facial expression. As Errol developed, I realized I might have made the jaw move from further back and be WAY sturdier. As it was, I needed a position sensor for the the movement, but the actual movement was not very much and getting a good signal was really hard. The frame of the jaw actually bent under opening force and the end position was always just a bit out from the last time. I ended up with gearing to move the sensor more as the mouth opened. (By facial expressions, I mean positioning of the brows, snout and ears)
A later addition was the three switches under the chin so you can move your jaw forward and sideways to activate them. But these need to be placed back a bit so you don't hit then by accident when you open the mouth. I did like the idea of tongue switches (like Joe's Blue Mountain fox has), just wanted to try these to see how they worked. (And remember, you can activate a combination of switches to run quite a few different routines)
Typically, there's more work to be done...

How much stuff can a techy fit into a nose? Well...
Errol's nose breathes; there's fans, lights, a smoke generator, the nose moves and whiskers wiggle. The electronics module attached to the snout carries all that stuff and is moved by a pushrod from a servo. I wanted Errol to simulate breathing depending on how hot he is, so the software determines a pattern.
But there's a lot more going on- a temperature routine activates the cooling fan for times on the dance floor. The snout lights suggest inner fire. And to add to the illusion, a fan and heated coil of thin wire produces smoke (more on that in another journal) The fibre-optic whiskers follow the nose movement and just look cool. The nose has a 'flashlight' to illuminate a dark room or light up a page of music in front of him.
The mouth part has a position sensor, blow sensor, 3 pushbuttons and an indicator light. The switches you activate with your jaw (ie each side and forward- combinations of these activate various routines) That's a lot of stuff! And there's a fair bit of software that interprets all that (like debouncing, polling for changes and dealing with timers)
No wonder I miss a lot of TV!

For a rather simple feature, eyebrows can totally change a facial expression. Look at a dog next time she begs- without that eyebrow droop, she'd never get that scrap...
Errol has a servo in each cheek with a lever and rod system to raise the brows. I made the movement quite slow and the amount they move dependent on other features. Like, a small open mouth position begins to raise the brows and a closed mouth lowers them again. So, they kind of follow the mouth in a similar way ours would do if you talk. I can also make them raise with a jaw switch, but if only I could sense the position of my own eyebrows... that is a task for a kinect or camera sensor, which I soooo don't have time to do right now.

Look at a creature's eyes- absolutely amazing. If I can even imitate a tiny piece of that...
So, having seen follow-me eyes, many beautifully done with lights, let's see what a techy can do.
Well, the eyelids should blink- seems easy right? Nope. The eyes should move- but how to control them? Hmmm. The iris could open- esential in a dragon after Smaug. And lights... even McCaffery described deep red light and swirling colour.
OK then. Moving the eyes is done with two servos turning plastic globes, controlled with a gyroscope on top of Errol's head. Now they follow the direction you're looking. But know that the software has timers and filters to keep the darn things from spazing out.
Eyelids that blink have cost me weeks of fooling around and I'm still not happy. I use 4 tiny servos, but they are noisy and not strong enough. Still, it's kind of cool that Errol does it all by himself, a little bit random and I can make him wink with a jaw switch
The iris is two fabric ribbons attached at the top of the globe, stretched a bit along the sides and pulled down by a cable from a servo. That is controlled by a jaw switch, but autofocus would be soooooo cool.
Now the lights. Well, that's tough because you look through there and light is the last thing you want in a dark room. I finally came up with a spherical lens and multicloured LED at the bottom of the globe. So I wanted the colour to change depending on Errol's mood. The hotter he gets, the eyes change blue to green. When he lets off smoke, they go red. And an ambient light sensor so that the light is never too bright. The software does all this autonomously.
Crazy complicated! So much fun to do. And ending where I began, any dog's eye shames my heroic efforts.

In an attempt to follow at least one New Years resolution, I'm going to keep a journal on Errol

Once again I am totally amazed at nature's handiwork-
A recent project of mine is to make the ears follow sounds around Errol. Rather than have 'psychic control' or hand switches to move them, they should do the moving all by themselves.
With 2 sound detectors in the horns it didn't seem it would be hard to do, but yeah... After several week's fooling around with the electronics and coding Errol's PIC chip, I finally came up with something that works; kind of.
So, the ears move forward when the jaw moves (like in talking), I can move the ears back with a jaw switch, and the ears twist in the direction of a sharp, loud sound.
The techy stuff?
The basic idea comes from having sound from the left add to a set voltage and sounds from the right subtract from that. The computer looks for a level that goes above and below thresholds and tallies the times that happens on each level. Eventually one tally wins and activates the ears. (oh, and the sound levels also activate several timers that trigger the lights)