Trying to build a "Lilac Chaser" illusion with Arduino

Hi - I would like to modify the LED Pendulum project into the lilac chaser optical illusion using Arduino parts. What size Breadboard should I be looking at? Which kind of resistors are best? How many jumper wires? The lilac chaser uses 12 LED lights. Here is a link to the illusion:

What size Breadboard should I be looking at?

Bread board is evil, use strip board and solder it all up.

Which kind of resistors are best?

The soft cuddly kind with a great personality. Failing that, one with the correct resistance value. Which you will know how to calculate when you know what current you want to use and what forward voltage your LED has.

What size Breadboard should I be looking at?
I don’t think you can get one so small that it would not hold your 12 resistors.

Which kind of resistors are best?
Carbon resistors are inexpensive and plentiful. Have you chosen your LEDs yet? You will need their specs to pick the right resistor value. (http://ledcalc.com) Don’t get LEDs that need more than 30 mA for fear of burning out your Arduino.

How many jumper wires? The lilac chaser uses 12 LED lights.
I assume you want to arrange the LEDs in a circle. If so you should get two Female/Male jumpers per LED so they don’t have to be stuck directly into a breadboard. Or you could learn to solder and connect wires to LEDs that way. The resistors can go into the breadboard. You will need to connect one side of the resistors together and to Ground so figure 12 Male/Male jumpers. Since they often come in sets of 40 for $4 you might as well get 40 of each. Throw in a set of Female/Female jumpers and you are ready for anything!

The 10 cm Male/Male jumpers are good for working on a breadboard and the 20 cm Male/Male jumpers are good for working between the Arduino and breadboard. You can get a pack of 65 Male/Male jumpers in several lengths which will cover both uses.[/quote]

I agree - if you know how to solder, use strip-board (at least once you get it working on breadboard)

The size of the the board you need is entirely dictated by how large you want the illusion to be. If the LEDs are going to be on the end of wires, instead of right on the board, even a little scrap of strip board or small sized piece of breadboard is fine. If the LEDs are getting connected directly to the breadboard/strip-board/etc, then obviously the board needs to be big enough to put the LEDs as far apart as you want them for the visual effect.

What kind of resistors?
Kind with the right value. You probably don't care about tolerance (and besides, modern resistors are usually far closer to their stated value than the tolerance would suggest, unlike in the old days). If you're driving small LEDs, directly off arduino, then anything rated for 1/8th watt power dissipation or higher is fine (for through-hole resistors, you can't even get ones smaller than that :-P). 1/4th or 1/2 watt is a better choice for future usefulness, while 1-watt ones get more expensive.

Metal film resistors are better than carbon ones, but it doesn't really matter much.

Personally, I'd grab an assortment pack of resistors, if you don't have already (this also gives you resistors to swap around until you decide how bright you want it). http://www.ebay.com/sch/i.html?_nkw=resistor+assortment
Be sure you get one with at least 12 resistors of each value :wink:
After a few projects, you can restock the useful resistor values.

What kind of LEDs?
The correct kind for what you want. Probably standard 5mm through-hole LEDs, but depending on what want it to look like, that might not be what you want. I'd grab an assortment, since they;re nearly as cheap as resistors.

If you want to use LEDs that can handle more than 20mA of current, and want to run them at full brightness, you'll need more components. I doubt you do though - you probably want to keep the LEDs fairly dim, so the illusion isn't overpowered by the funny things that happen to vision after looking at bright lights.

How many jumpers:
At worst, 2 per LED, plus 2.

You'll probably need a diffuser in front of the LEDs to get the visual effect to look right - a sheet of paper or vellum held in front of the LEDs is a good starting point. It looks surprisingly good for what it is.

get up on this bad boy