For more detailed pictures, go to:
This project require some experience with tools, electronic circuits, and maybe a little programming.
Here is a sample video of the turret:
Here is the completed turret:
Let's get started!
Note: This turret was NOT designed to be very good at tracking and shooting - it's more for show than functionality. If you are one of those people who have nothing better to do than criticize other people's Instructables, just close the screen.
Step 1: Electronics Pt 1: Overview
There are plenty of Arduino Instructables here, I would reccomend reading through them if you are unfamiliar with them.
I used a lot of breakaway headers and hook-up wire to make all the connections to the Roboduino.
Step 2: Electronics Pt 2: Sound
So far I have only found one easy to use and cheap sound player for the Arduinos - the wave shield from Adafruit industries. It only costs about $25, much cheaper than other sound playing development boards. Also the coding is fairly simple with the libraries provided by Adafruit.
The disadavanges do pile up, though. It can only play uncompressed WAV files - in mono. It needs 8 connections do the Arduino. It takes a minimum of 10kb of flash on the Arduino - leaving only about 4 or 5kb left on the Arduino for the rest of your code. However other MP3 player boards usually run for around $100, so I just stuck with the wave shield.
I changed the dac.h file in the wave shield library to use analog pins 2-5 instead of the digital pins. I wired up a speaker to the base of the turret.
Step 3: Electronics Pt. 3: LED Lighting
I would reccomend going to eBay and buying an LED assortment. Whenever you need a color, you'll have it on hand. I purchased 7 colors of LEDs, 15 LEDs for each color, for about 6 dollars shipped.
If you want to drive more than one LED on the Arduino, you will need to use a transistor (basic schematic shown in pictures).
The LEDs are connected to the digital ports on the Roboduino, and used the digitalWrite command to turn the LEDs on and off.
Step 4: Electronics Pt. 4: Movement
Servos can be purchased online or at your local hobby shop, and they usually cost between 10 and 15 dollars. The Arduino software has support for servos, making servo control as simple as a single line of code.
Step 5: Mechanics Pt 1: Materials and Tools
The majority of my turret is constructed from Sintra expanded PVC plastic. It can be formed and bent by heating, and is easily cut and drilled with hand tools. To connect the varioius Sintra sheets together, I used right-angle mounts from Budget Robotics - you can pick up about 10 right angle mounts for just a buck or two.
There are a ton of nuts and bolts on the turret, and they all came from cheap dollar-store assortments - very handy and cheap. If quality is important to you, I would reccomend going to a hardware store for your nuts and bolts.
I used the following tools (plus a few other basic ones like screwdrivers or pliers):
Step 6: Mechanics Pt 2: Gun
Before mounting it I cut off any excess plastic to streamline it a little - I followed this tutorial to cut off the extra stuff:
I then made a bigger hopper using an old fruit-2-o bottle.
Step 8: Programming
Note that you will need the SoftwareServo library and the Wave shield library.
Step 9: Tracking
Step 10: Green: Solar Charged Batteries
I opened up one of those solar-outdoor light things and found a simple circuit and 3 AA batteries inside! The solar cells would charge the batteries during the day. I replaced the flimsy wires with stronger hook-up wire, and soldered on connectors to the terminals - now when I want to charge the turret, I just have to take the battery outside for a day and I'm set.