Hi all,
I am trying to make an exhibition stand for my uni course. It will be running a flash movie in a darkened booth. When a button is pressed a flash movie will run. The movie will make lights flash and music play in time with the video content. There is also going to be a roll of paper on spindles (about 84 cm wide 4m long) that is hidden behind a curtain. For each of the different movie options there will be different sheets, a motor will rotate the spindles to align the right sheet in front of the viewer and then open the curtain and a light will shine on it...
Ingredients:
15 white LEDs will need to be able to fade in and out.
10 green, 10 red and 10 amber LEDs will be required to flash on and off.
7 more powerful LEDs will be needed to illuminate specific areas of the exhibit as and when the flash movie tells them to.
A motor will need to attach to spindles via belts to rotate approximately 500g of paper CCW and CW.
Two curtains of approx 500g will need to be drawn and closed by their own motors (they will be closed by gravity).
A keypad with four buttons will signal which part of the flash movie to play.
So that's my plan, I'm completely new to hobbyist electronics, although I know my way around programming languages and most of the terminology involved. Unfortunately the electronics knowledge I possess is out of date... For example, I can't remember why I'd need to plug a resistor in front of an LED, nor would I know what resistance it would need to be. But I do remember that Voltage = Impedence x Resistance.
I've worked out all of the mechanics for the project, but I could really use some help with picking the right electronic parts. All that I've worked out so far, is that if I'm going to buy an Arduino Microcontroller, I'll need the Mega one. 
Will the white LEDs operate all at once, or individually?
Will the colored LEDs operate individually, or as a group?
What about the "more powerful" LEDs?
More importantly, do you know how to make the Flash movie trigger events on the Arduino? Flash movies are created with software that is far from free. That severely limits the amount of help you can get on this forum when you have issues with Flash.
Thanks for the quick reply Paul.
I've got flash covered. I'll be running it in Action Script 2. I've taken a cursory glance over the code libraries and actionscript is quite happy communicating with other programmes and the COM port.
As for your other questions: All of the LEDs will need to operate individually. The more powerful LEDs are also to operate individually, acting as spot lights within the darkened booth. They will need to provide strong white illumination of about 300-400 lumens.
They will need to provide strong white illumination of about 300-400 lumens.
That sounds like a power LED is needed, these require special circuitry to drive them. This is called a constant current supply. You can buy these but the cost will add up.
Two curtains of approx 500g will need to be drawn and closed by their own motors (they will be closed by gravity).
You will need something like a micro switch to detect when they are open so you know when to turn off the motor.
10 green, 10 red and 10 amber LEDs will be required to flash on and off.
Looks like you will need at least two port expanders of the 23016 type.
but I could really use some help with picking the right electronic parts
It's not just that it is putting them together, for a first project the is way over ambitious.
You're right mike, this is overly ambitious, so I'm splitting the project up into parts. That way I'll learn the ropes with simple things, like the LEDs, once I've got the hang of controlling those from software I'll look into the more complex elements. I've given myself 9 months to complete this project, so I'm confident I can make it happen by then.
I appreciate the support so far, many thanks.
I've given myself 9 months to complete this project
Excellent, we get so many people with such a complex project and they say it has to be ready next week. Given that amount of time you should be able to tackle it.
so I'm splitting the project up into parts
That is the correct approach.
For the lots of LEDs see the port expander on this project:-
http://www.thebox.myzen.co.uk/Hardware/MIDI_Footsteps.html
There is light at the end of the tunnel, I can understand schematics again, the chipsets and the terminology all make sense now (mostly); and I've made my first purchase, the Arduino mega starter kit and a few extras is on its way...
I'm sure you'll be hearing from me again soon :-*
thanks for hijacking the thread 
Those websites weren't useful at all... is this spam? :o
is this spam?
yes he made 50 identical posts at the end of every thread he could find.
We banned him.... and I had to manually delete all the messages..
m
We banned him....
Thanks!
and I had to manually delete all the messages..
Bummer. 
I hope everyone reading this message has a good weekend! And even if you don't read this Massimo, I hope you have a good weekend!