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By Mstaffa81
#174189
Hello folks!

So I discovered Arduino and all that fun stuff from my brother, who had an arduino Uno (which I promptly "borrowed").

After that, I began thinking of what I could do with it, and I settled on building an EL-Wire dance suit, which my friend would wear and dance in, and I'd run maintenance on.

So... "Why is a total n00b trying to build something so complex?" You may ask yourself... My answer, why not?

Anyway, there are three main aspects to this suit that I wanted to brainstorm in the forums for ideas, stress tests, and general fact checking (basically will it work and how do I do it).



1) Wireless vs. Stand-Alone modes:

I've got two xbees, and an xbee board for lilypad. I wanted to known if it was at all possible to have the wearer choose between being wirelessly controlled (by me with a laptop off to the side) or in standalone mode, where he will be controlling set light modes via buttons on the suit.

2) Different lighting modes:

This one I've already pretty much got figured out. I want the suit to have two different light modes, one with red and one with blue. This is pretty simple to achieve with two-circuit micro-relays, which the arduino can control pretty simply. One will control the power flow and the other will control which color set the power will flow to. So, either red or blue, and what rate they strobe at.

3) Lastly, would be power supplies.

This seems to be the issue with any prototype or machine. How to get a solid amount of power, for a reasonable amount of time, and keep it light and compact. I've turned to the Lithium ion battery solution, in conjunction with the arduino LiPower board. The EL Wires have their own power packs and inverters, so that doesn't become an issue.

Basically, I'm a hopeless noob to progrqmming, but I have a pretty good knowledge of electronics and I'm determined.

The materials I have to work with:
- several strands of EL-Wire and EL-Tape
- multiple (5) electrical inverters
- arduino Lilypad main board
- arduino Lilypad usb board
- Arduino lilypad LiPower (power supply)
- regular lilypad power packs
- small button battery power packs
- lilypad conductive thread
- 2 Xbee Pro s
- 1 Xbee explorer board
- 1 xbee lilypad board
- A computer (obviously)
- several Lilypad LEDs
- 7 RGB LEDs
- 5 micro-relays (for el wire switching)
- multiple small circuit boards
- soldering kit and skills
- absurd determination



Basically, the coding and layout are what I need help with. Xbee in particular is incredibly confusing to me.

Thanks guys!
By Mee_n_Mac
#174206
You may want to look at this instead of all of the above.
https://www.sparkfun.com/products/11323
Features:
ATmega 328p running at 8MHz, with Arduino bootloader
Eight opto-isolated, zero-crossing EL control channels
Headers for XBee and NRF24L01+ for optional wireless control
No library needed - control is as easy as turning a LED on and off
Integrated 1.5A linear regulator (LM317) to supply regulated DC power to external inverter
Linear regulator preset to 3.3V, but can be changed via PTH resistors, or bypassed entirely
Can be powered by a 3.7V Lipo battery (using 3V inverter), or an external 3.3V to 16V supply (using 3V or 12V inverter)
5V FTDI BOB or cable required for reprogramming, not included
External EL inverter required, not included


And while this tutorial is for the EL shield for an UNO, it's also good reference for the above all-in-one EL Sequencer.
https://www.sparkfun.com/tutorials/353
By Mstaffa81
#174215
Hm. That is actually a very good suggestion, but I'm not sure where the power for that will be coming from. I need to be able to run around 5 strands (that's an exaggerated estimate) at any given time, and the product specifications state that anything nearing four will be pretty dim. I could bump the power to twelve volts, but what battery do you know that can pump that out consistently for more than 20 minutes? I don't think dancing with an extension cord is too ideal :P
By Mstaffa81
#174216
I do however, like the any features it seems to provide, so perhaps I can run some of the main wires with this, and some others through my suggested relay system
By Mee_n_Mac
#174228
Mstaffa81 wrote:Hm. That is actually a very good suggestion, but I'm not sure where the power for that will be coming from. I need to be able to run around 5 strands (that's an exaggerated estimate) at any given time, and the product specifications state that anything nearing four will be pretty dim. I could bump the power to twelve volts, but what battery do you know that can pump that out consistently for more than 20 minutes? I don't think dancing with an extension cord is too ideal :P
The question is what's the total length of your strands ? Your comments above are referring to the 3V inverter that SF sells ? So use the 12V inverter, which sounds like it'll run a lot of EL wire. Then you need a 3S LiPo (3 single cells in series so as to increase the voltage) or use a single cell LiPo with a boost (DC to DC) converter to step-up the voltage. The first may be simpler but you'll need a proper charger for the battery. I don't think SF sells either (3S battery w/balancing taps and charger) but they're available, look for stores selling RC plane "stuff".

The second means having a battery and DC-DC and then the inverter. And perhaps a separate (readily available) charger for the single cell LiPo. You might be able to get a combined charger/DC-DC board. If not Pololu sells small DC-DC converters. The only question in my mind is how much 12V current does the inverter draw when running all your EL wire. That's something you could easily measure (or perhaps e-mail SF tech support and ask them). I get conflicting answers as to how many mW/m EL wire consumes. The SF datasheet lists anywhere from 100 to 1000 mw/m. If you had five 3m lengths, that's 45m and so somewhere between 4.5W to 45W. The latter would be a problem but the former is easy for a LiPo powered system.
By Mstaffa81
#174229
Each strand is 3m. Would perhaps shortening them accomplish a brighter light with less voltage? Since I don't have the actual clothing yet (having trouble finding exactly what I would like), I've just been calculating for the full length
By Mee_n_Mac
#174232
Shortening them will consume proportionally less power and thus increase the battery life. It may not make them much brighter, it depends on the inverter and how "taxed" it is driving the length. Since inverters generally don't allow you a choice of voltage (it's > 100 VRMS) it is what it is. Could you run a nominally 12 V inverter on less voltage, say 2 LiPos in series (~7.4 V), and have that work with a shorter lengths ? Good question, I don't know. It would depend on the inverter design and I would guess there's some min voltage input for it to work at all. E-mail SFE tech support with that question.

ps - one other thing to be aware of ... some inverters do not like being disconnected from a load. They depend on some min length of EL wire being attached or else bad things happen. SF says theirs all operate w/o any load.

pps - It occurs to me that maybe, just maybe, if really needed, the EL Sequencer board could be modified to allow 2 inverters to be attached and to split/divide their outputs to go into different output channels. For instance channels A, B, C, and D could run off one inverter and E, F, G and H the other inverter. I'll have to look at the board design and see if there's a place where an easy cut w/an Exacto knife will do the trick.
By Mstaffa81
#174235
I'm afraid my knowledge of electronics is somewhat limited with conversions and loads, especially when dealing with AC currents. A board with two driver inputs would be good, but inworry about the effects on some of its features
By Mee_n_Mac
#174239
Well the 1'st thing to do is get a real good estimate on the total length of EL wire. Everything depends on that. No need to make things complicated if it's not really needed.

FWIW here's the kind of battery that should run one of SF's 12 V inverters at it's max power output (9W per the datasheet) for just under an hour. If that inverter can really drive 30 m of EL wire at your desired brightness and if you find 30 m is enough ... then you're all set.
https://www.sparkfun.com/products/retired/10470
https://www.sparkfun.com/datasheets/Com ... V12M-1.pdf
By Mee_n_Mac
#174240
Here's some interesting data on power consumption. These people tested all the inverters they sell with the min and max lengths of EL wire allowed by the inverter specs. They used 3 different EL wire types. SF sells the 2.2 mm type and Adafruit sells both that and the brighter 2.6 mm type. They measured the input current drawn by the inverter for each case and computed the total power drawn from the source (wall-wart or battery). The data looks fairly consistent across all their 12V inverters, implying that they're all about the same efficiency.
http://www.thatscoolwire.com/articleDet ... ticleID=67
So for the "normal" EL wire, 104' (31.7 m) required 3.36 W using a 12 V inverter. That would mean under 0.5 A for that 11.1 V battery above and a good 3.5 hours of run-time if you had 45 m of EL wire on all the time. Better than I had thought !

It also means that a small single cell LiPo combined w/the DC-DC converter linked to above is an option.
By Mstaffa81
#174252
Wow! You're really good at this XD

With that information, and an old jacket I have for a mock layout of the wire and all its lengths and the component layouts, I can probably get back with a good estimate of my power needs :3
By Mstaffa81
#174325
Hey! So I'm working on that mock layout for the el wire lengths and such, but another thought occurred to me while I was drawing out the suits sketches. Can I have a pin on one lilypad turn on, while connected to a pin on a different lilypad, and have the receiving lilypad interpret that as a switch? It would free up a large number of pins if I had a different arduino controlling the LEDS, while the main board is controlling the EL Sequencer and other things
By Mee_n_Mac
#174397
Mstaffa81 wrote:Can I have a pin on one lilypad turn on, while connected to a pin on a different lilypad, and have the receiving lilypad interpret that as a switch? It would free up a large number of pins if I had a different arduino controlling the LEDS, while the main board is controlling the EL Sequencer and other things
Yes you could do that ... and more. You could use a single pin on each board to make a 1 direction UART, aka a serial link.
http://arduino.cc/en/Reference/SoftwareSerial
And send more data over the link than a single bit. Use another pin on each and the link can send and receive messages.

IIRC the "Arduino" on the EL Sequencer has 5 or so spare "analog" pins available and brought out to the header. Since analog pins can also be digital I/O pins I have to ask ... do you really need another Arduino/LP mainboard ?
By Mstaffa81
#174475
Hm. If I DID get the sequencer, I would want to use Xbee to control it with a program on a remote computer. Do you know anything about Xbee and how to do something like that?