Arduino Nerf Project (Need some Help)

Projects General Guidance
1

I have an idea to convert a Nerf Firefly into an energy weapon looking Kriss Vector and have a few questions/ideas I'd like to bounce off of more knowledgeable people.

Arduino to be used (unless there are other suggestions and reasoning why):
Arduino Diecimila (grandfather of the Uno)

What I'd like to do is the following:
Have a light (LED, unsure if I'll use 1 small one or a 3/5W one) that either lights up a clear 1 foot barrel. I've been looking at the local hardware stores and it seems they only have flexible clear tubing rather then something rigid. I'm not sure how much of the light will be diffused out of the clear plastic, so I was wondering if a regular 1 foot tubing could work with something on the end to allow people to see that it lights up when the trigger is pressed.

In the two opening gaps near the butt stock of the gun I was thinking of putting an 3 or 4 7-segment LED on one side to act as a pretend virtual counter, with the other side either mirroring it or just having a clear plastic covering it with a light illuminating it. There is no where else on the Nerf gun to place an LED ammo counter as I want to be able to take it apart as shown in the pictures below.

I was also thinking of installing a pizo or a buzzer to indicate/playback an audio track/noise/sound when the device is fired and when it's "empty".

I'd also like to have when the device is "empty" to have some kind of spring or mechanism that is illuminated and ejects out of the back. Requiring someone to push it back in to reset the ammo. Not quite sure what to use with that.

Where the 2 AA battery pack that's built into it I was thinking of replacing it with a single 9V battery pack/holder to supply the Arduino with enough power (and not take up a bunch of space).

I don't have to worry about capturing the trigger being pressed as a limit switch (Or a contact switch, been a little while with component part names) is already wired. I'd just need to feed it into a digital in. Same goes with the on/off switch, it's already wired in.

Here are some pictures of the Nerf Firefly at it's current un-assembled state:

http://img337.imageshack.us/img337/8895/picture1ova.jpg
http://img37.imageshack.us/img37/9278/picture2hp.jpg
http://img856.imageshack.us/img856/3252/picture3nt.jpg

2

Sort of surprised no one has anything to say about it, recommend parts etc after so many views alread :frowning:

3

I've been doing some parts searching, and realized if I want a high lum LED/light to shine out I'm going to either need to use the motor shield for/with the ardunio or use a buffer chip (can't remember for the life of me what they are called) to increase the current I can drive without damaging the digital out port. What is the type of chip I'm looking for called again?

4

The word you're looking for is transistor. There is a whole section of the forum devoted to the subject of powering stuff via transistors and so on.

Forget the idea of powering anything from a PP3 9V battery. They're a hideously expensive way to get a feeble amount of current, and most of the energy they give you will be chucked away by the Arduino's voltage regulator. I suggest you look at a set of four AA rechargeable NiMH or similar in a holder.

I assume you have ample space inside your Nerf Firefly (whatever that is). Most of the problems you're describing are purely hardware and styling issues and nothing to do with Arduino, but the functions you're describing sound pretty straight forward to control with an Arduino.

5

Well thanks for letting me know about avoiding the 9V to power the arduino, though how much under 5V will the voltage regulator take to balance out the 4.8V the rechargeable batteries will supply.