Team Tracking - Retrieving the Payload
TEAM TRACKING - PROGRESS REPORT 2
Our team was responsible for organizing and coordinating different devices to develop a comprehensive tracking system to retrieve the payload. However, along the way we faced several obstacles, but ultimately were able to overcome them.
As a team we chose to employ the use of a SPOT Trace satellite GPS tracker, a tile locator, a cellular GPS tracker, and a Radio Bug and APRS transmitter. We had trouble figuring out how to make the cellular GPS tracker work and we decided not to use it. Another obstacle was that after 4 minutes of no motion, the SPOT device would enter a “camp setting” where it would stop reporting its location. The purchase of a Radio Bug and APRS transmitter was an option to help provide us with a greater chance of retrieving the payload. Together these two devices track the location of any object using radio waves.
We partnered with members from the Tallahassee Amateur Radio Society to learn more about our device and test it out with their help. They provided helpful tips for securing the tracker on the payload as well as directing us the closest radio tower on Bannerman Road here in Tallahassee. The APRS transmitter reported location and altitude data constantly which provided our team with enough confidence that we would be able to follow the trajectory of the payload using the SPOT. Then, we would use the final location that the SPOT sends out paired with the Radio Bug data to locate the payload wherever it landed.
The weather forecast for our original launch date of Saturday, April 2nd was strong winds and rain. We decided to move our launch to Sunday, April 3rd hoping that the weather would have some strong winds from the storm that was leaving Tallahassee, but that the jet stream would not be too risky for us to continue with our planned launch. However, the jet stream was predicted to be too strong and several websites used to predict the trajectory and resting location of our payload put it in the Atlantic Ocean. Therefore, our launch was rescheduled again for Monday, April 4th still with strong winds, however with a final resting place near Jacksonville, Florida.
Our team ran launch predictions for Sunday after the weather for Saturday was anticipated to be too stormy for a launch. As a team we discussed the possibility of changing our 600 g balloon, our parachute (1.5 m in diameter), the amount of helium we put in the balloon, or the size of the payload. We decided not to alter any of these variables and kept our rate of ascent at 4.5 m/s and are rate that was less than 7 m/s. This gave us a final prediction for the final location of the payload between Tallahassee and Ferdinand Beach.
The payload was retrieved from a potash mine near Live Oak, Florida. The difference between the final location as reported by the SPOT tracker and the Radio Bug was only 80 feet. The payload was actually in the middle of those two locations. Therefore, our tracking system was a success and for future launches it is valuable to have a backup system (ie. the Radio Bug and APRS transmitter) to help ensure that the payload will be found when using the main device (ie. SPOT tracker).
