On this mission, it simply reads serial from the main processor and returns information from the accelerometers. There are three accelerometer on the perimeter of the satellite measuring the acceleration towards the center. Originally we were going to calculate the RPM live on the processor, but we ran out of time trying to solve the equation. Oh yea, we are using this to find out the RPM of the satellite and center of rotation.
Now that I think about, the main board on Pollux probably has the arduino boot loader too.
The overall goal of the project is this.
- Provide Total Atmospheric Density for Orbit Determination and Collision Avoidance
- Validate Fundamental Theories on the Calculation of the Drag Coefficient
- Provide Calibration Objects for SSN
- Establish a Method to Validate Neutral/Ion Density and Composition Derived from DMSP Sensors
- Space to Ground Optical Communication Experiment
Number 2 is a big one.
Also, Pollux is testing how well commercially available devices (sensors) work in space. In this case the accelerometers I picked out for it is as fallows.
The SCA610 from VTI. The 10bit A/D converter on the atmega168 gives us about a 3 RPM accuracy, but higher do to my sampling.
I also used the arduino environment to control our high school ground station. The device I made is the Goldberg-1000. Uses USB serial communication and a series of mosfets to control motor rotation. It is accurate within 2 degrees. Future one will use UDP/IP to control it, this board will be quite a challenge. NRL decided to fund these boards, seeing they are the best on the market :), I am only 17, hehe
Here is the Goldberg-1000
Here is the Schematic of the Payload.
