LED Help

[Not Kuno]

I would like to make a costume that lights up. There are quite a few ways to do this. The thing is it will have to alternate colors. It will also require a bit of LED lights/lighting so it's a big project, sort of. Anyway, I have a few options:

1) Regular LEDs -
Probably the easiest to work with but one color. Unless I jam LEDs everywhere, but that'll be way too crazy.

2) Electroluminescent wire -
Too thin. The effect I'm going for is like a panel lighting up.

3) RGB LEDs -
This is might be what I end up going with. They make thin strips and I can probably work it to for my outfit.


Anyway, I am really awful at anything electric related. A few strips I saw that were good were either:

http://www.theledlight.com/flexible-RGB-strips.html
or
http://www.superbrightleds.com/morei...t-strips/1388/


I have been looking at controllers and it seems like theres no way to program a pattern. Or if there is, I have no idea how. The ones for sale have ways to change the colors, or a few predetermined patterns but I can't find what I want. It is also pivotal to have some of them be different colors. Does that mean I have to get multiple controllers?

Anyway, the finished thing is supposed to look like this coat:

Spoiler: show

http://images.wikia.com/mspaintadven...rdEnglish2.gif

Anyone have any advice to help me out? I have literally no idea what I'm doing. It looks easy enough to put together, I just have no idea how to get it to do what I want.

[Fairy-Killer]

You can get a very tiny Cypress PSoC that's powered by a 9V battery. You can pretty simply program the device to provide a voltage over certain ports and timing. People in my class even did a 3D cube of LEDs controlled by it.

From that first link you posted:

Using a simple RGB LED color controller, RGB LED strips typically produce seven different colors and effects like flash, fade or strobe. More sophisticated RGB color controllers are available to give you even more color choices and more dramatic lighting effects.

So I imagine you could probably just buy their controller. I don't know how you would change colors otherwise.

[Not Kuno]

Yeah I saw that bit about the controller. So I have to buy a PSoC and the controller? So how would that work in regards to setting it up and such. Like physically and programming.

[Fairy-Killer]

Well, it appears that the controller can do patterns also, but you're going to have to sync a lot of them up/turn them all on at certain times it seems. They also control the color of the LEDs (not quite sure how this is portrayed to the LEDs and might be able to be mimicked by a PSoC).

Physically, it really depends on those controllers. They might have to take a certain voltage and the PSoC only provides a certain output voltage on the lines. To lower a voltage, you'd have to do a resistive divider and depending upon this you would need lots of them. Maybe some capacitors for a more stable rise in voltage. I didn't work in a project with LEDs and this is just my general assumptions on the subject, I'd really need to get my hands on some of this stuff to see how it works. Unfortunately, the university owns all of the PSoCs and I'm no longer in that class. You'd also need to do some soldering and lightweight breadboards.

Programming wise, PSoC uses a highly modified Visual Studio like UI with a hybrid C language. It is overall pretty simple to code on and set up. A FPGA might also work for this, but I don't have as much experience with them and timing.

I'll look up some stuff on this instead of talking out of my ass and see what I can turn up for you.

[Fairy-Killer]

Oh shit, totally forgot, you'll probably need some decoders. They're simple devices if you know binary. I think the most common decoder is probably a 3 to 8. Basically it works as so:

3 input pins, 8 output pins.
Call inputs in0, in1, in2.
Outputs out0, out1, out2, out3,... out7.
Low voltage/ground is 0, high voltage is a 1. (Basically means, voltage present or not)
Think of in0, in1, and in2 as your three bits and the outs as the number that represents those bits in decimal (normal numbering). If in0, in1, and in2, are all 0, (000) then out0 will be on, if in0, in1, in2 is 010, out2 is on. in0-2 is 111, out7 is on.

You can find the logic of these devices all over the internet. Also, I figure your project is realizable with a PSoC as plenty of people seem to be doing shit like this:

[Not Kuno]

Damn. That looks sweet. So what do I need to buy? And how do I set all this shit up?

Like can I buy just a 3 foot led strip, with a transformer and color controller.. and also a PSoC and a decoder? And can I just fuck around with that? I want to know if I can still sort of.. attach the 3 foot strip to whatever longer I get later.

I know binary (I have a binary watch, haha), but I don't know jack shit about coding, wiring, or anything like this. Kind of glad I don't need a shit load of color controllers and batteries. That'd make me crazy.

[Fairy-Killer]

Hmm... I don't know exactly what you'll need, but my current guess is that you could get a PSoC that could provide high/low voltage on at least three ports to input to the decoder. You could then vary what wire is high/low via coding to provide voltage out of the decoder to strips of LEDs (possibly through the color controller and such, not sure how that works). I feel like that basic setup should allow you to make some progress. I would also check what kind of voltage/current is required to turn the LEDs on. Typical turn on voltage for a diode is 0.7 V, iirc. Oh, and you'll need a plain old breadboard for hooking everything up for practice. A lot of people use it for starting and then move on to the honeycomb type material that is very lightweight and can allow soldering for the final project.

[Fairy-Killer]

Looking into the transformer thing, it looks like you might have to find some sort of extra voltage as these LEDs seem to require 12 VDC which is well above what the PSoC can output.

[Not Kuno]

Your saying words, I just have no idea what they mean. I have no clue about any of this terminology. >_< To start with, is there any chance you can link me to what I need to get started? Will I need multiple PSoC's for making different stuff different colors? This is why I'm so awful at this. I figure once I get everything that should theoretically work, I can keep fucking with it or trying to code it or whatever do see if I can get it to do something.

And yeah I kind of figured I'd need a 12v battery. That's what all the RGB LEDs seem to require.

[Fairy-Killer]

All right. Let's do a quick electrical engineering lesson for ya.

LEDs - Light Emitting Diodes, but you're probably wondering, what the fuck is a diode?

Diodes - Basically, this is a device that only allows current to flow in one direction. So basically, you provide enough voltage on one side (it's called the anode, cathode is the side that you want to be lower voltage) of a diode, it will turn on, thus producing light in this case. Normal diodes would just simply allow for current to flow forward but not backwards. The voltage difference between the anode and cathode varies depending on the diode, but it is typically very small (0.5 V - 0.7 V).

VDC - Voltage (direct current), this means that it is a stable voltage with a stable current. Stable current meaning it flows in only one directly. If you were to hook this up to a oscilloscope (a device used to passively observe voltages vs time), you would see a flat horizontal line at the desired voltage. This type of voltage is produced by things such as batteries.

VAC - Voltage (alternating current), produces an oscillating current because the voltage is constantly flip-flopped. If you were to hook this up to an oscilloscope, you would observe a square wave with ripples after the rising and falling edges (when the voltage goes from low to high/high to low). This type of voltage is produced by things such as our electrical outlets in our homes.

Breadboard -A very simple piece of hardware that electrical engineers use to build and design circuits before building a final design as they do not require soldering. In the linked image, every hole that is on the same horizontal axis (vertical to us, but I say horizontal because of the numbering) as the numbers share a common piece of metal and will be connected if wired into that spot. This is called a node. For example, row 1 and 2, even though very close in proximity, are not connected in any way. The nodes from the + and - (seen on the top and bottom of the board in relation to us) run vertically, so every hole beside the red + is connected and every hole beside the blue - is connected. These are not connected across the board, however. That means that the ones at the top of the board are not connected to the ones on the bottom. Usually, people use programs to produce schematics and run simulations before breaking out the breadboard, though. So what the fuck are schematics, simulations and did you say something about spices in there?

Schematics - Simplified drawings of electrical components and their connections to get a decent grasp on the theory behind them and the math. Click the link for an example. Probably should go over a few symbols on that. VDC, VAC, resistor, diode, and ground. So how the fuck does one go about making a schematic and playing The Sims 3 on it? Or whatever that sim word was that you used.

Pspice, student edition - This is software that will allow you to quickly create schematics and run simulations to determine voltages and currents at certain nodes (hey! you said that earlier!). You can also see how the circuit will react over time and is overall a very good program for simple circuits such as this. There should be several videos that help in using this program. But first, you should probably understand certain basic circuit elements.

Basic elements
Link explaining basically everything in this part, in a slightly interactive way. This really pains me to send you to UT as they are our sworn enemies, but whatever I'm tired.

Resistor - A simple device that dissipates a certain amount of voltage and creates a current in the progress. Voltage = Current * Resistance or (V = I*R) is the most fundamental equation of circuits. Say you have a 12 V battery across a 1000 ohm (the measure of resistivity of a resistor). So very simply 12 V = I * 1000 which is very easy to see that the amperage produced is 0.012 A. However, what happens when you have two resistors in a special configuration? Say, the 12 V battery connected to one end of a resistor, with that resistor going into another resistor, with the remaining end grounded?! Hold on, we're getting ahead of ourselves. For this reason alone, I'd like to suggest a more... Explicit form of V = I*R. Vhigh - Vlow = I * R. This simply means that whatever side of a resistor has the higher voltage connected to it is high, and the other side is low. It still holds for the first example I explained. 12V is high and 0V is low, as ground is 0V and is connected to the other side of the resistor. 12 V - 0 V is obviously the same as what we had on the left side of the equation earlier. Now, with this in mind, we can introduce a few more advanced things.

Kirchoff's Voltage and Current Laws (KVL and KCL) - KVL basically states that the sum of the voltages in a closed loop must be equal to 0, and KCL basically states that the sum of any currents coming into a node must be equal to 0. These are a bit harder to explain than a simple block of text can give. I'll just leave it to the link provided to help you with this.

Series and Parallel - Shit, he skipped around! This terminology is useful for quickly determining a circuit layout. These two terms can be associated with things we already know about computer processors. If you do an action in series, that means one comes right after the other. If you do it in parallel, that means they are happening concurrently and side-by-side. So what the hell does that mean when I say resistors are connected in series or parallel? This means that in series, resistors share one common node, the point where the Vlow side of a resistor touches the Vhigh of another resistor. How about parallel? This means that the resistors share two common nodes. Their Vhighs are the same and their Vlows are also. But what does this do to voltages and currents? Well, in a series circuit, current is the same and voltage is a fraction of the original based on the resistors. In a parallel circuit, the voltage is the same and the current is a fraction of the original based on the ratio of the resistors. These ideas are key in understanding another very important part of electrical engineering. Voltage dividers.

Voltage Dividers - God dammit, Killer, it's too early for math! No, no, these are very easy, I swear. Basically, these are very simple resistor circuits. It requires two resistors in series. Say we have a 12 VDC that we want to reduce to 9 VDC. Well, this is a pretty good time to do this since you will probably have to to reduce weight/space/etc in your costume. So, our VDC = 12 V and say we have resistors R1 (which is connected Vhigh = 12 V and Vlow = Vhigh of R2) and R2 (which is connected Vhigh = Vlow of R1 and Vlow to ground or 0 V). We will probe the voltage at the low end of R1. Well, this knowledge allows us to form some equations namely:

Wait... Fuck derivations, give me the good shit.

Basically, the voltage at the low end of R1 is equivalent to (R2/(R1 + R2))*VDC. Well, we know our desired output voltage and desired input voltage so we can change the resistances to anything we want to produce the desired voltage. However, a lower total resistance means a higher current. A run down with pictures can be found here.

Well... I can't think of anything else right off the top of my head so I guess I'll end our lesson here. That might also be because I'm concussed, and it's now 4 A.M. As for PSoCs, I have used this one and this one. The second one is about half the size of the first but requires soldering immediately to use some the circuit components. It should only require one PSoC to power everything. Shoot me a PM and we can Skype in some of my free time and I can maybe give some tutorials on Pspice and shit. I don't know how much I've really helped, though, lol.