Mechanical Components 

Thrusters:

We have constructed our thrusters out of high density plastic round stock using a 30 degree half angle counter sink, and a 1/8" drill bit for the throat. High density plastic was easily accessible and would perform perfectly in the given conditions. 

Solenoid Valves

The solenoid valves we will be using are linear actuators. When a voltage (12 V) is provided, the solenoid actuates and the flow is cut off due to a metal structure which blocks CO2 from flowing  to the thrusters.

Problems that occurred:

    Originally we received incorrect solenoids that where originally for liquid. The pressure was therefore to great and the solenoid would not correctly operate. Since then, the correct solenoids were ordered and attached to our device. After applying these new solenoids to our configuration, completed the working thruster design.

    

Frictionless Environment:

We will be using wheels with high quality, low friction bearings attached to the base of our unit to simulate our frictionless environment. Originally we planned to use an air table because of its extremely low friction but due to uncertainty in the balancing of our prototype, we feared this method would be unnecessarily complex. 

Control Software

Fedora 8 is set up and running.
Buildroot is set up
File transfer between device PC and gumstix is working
App skeleton partially completed

To Do

Mechanically - Mount the wheels and bearings

Control -  Finish app skeleton
INTERFACE WITH HARDWARE
Determine whether a custom device drive program movement logic code must be written

We'll be scrapping the control computer interface and most likely the bluetooth as well.  It's enough that the satellite tracks the infrared source to move underneath it and the control interface is superfluous in the context of what we're trying to accomplish.  The bluetooth was really only used for the control interface...otherwise it's just a convenience, but one that we may not have time to set up.