Payload 12 Information

Abstract:
The purpose of this project is to develop a passive attitude determination system to derive the pointing direction of the data recording instruments on the proposed HARMEnI balloon flight. For accurate analysis of the recorded data the pointing direction must be known to within 2 arc minutes. The orientation system must be capable of this in both day and night hours, in the low pressure and temperature environment of high-altitude balloon flights. This will be accomplished using a two-part system: a star tracker for the night sky and a sun camera for the day. The star tracker uses a CCD to take photos of the sky which will be analyzed and compared to a catalog of stars after the flight to determine the pointing direction. The sun camera will take photos of the sky during the day with the intention of locating the centroid of the sun after the flight. Along with a GPS and a dual-axis tilt meter the photos can be compared to an expected location of the sun centroid to derive the pointing direction. These systems will be controlled by an Arduino Uno microcontroller. All data will be time-stamped and stored on-board for analysis after the flight