Abstract

This paper discusses the calibration and implementation of a low-cost attitude determi- nation system for high-altitude balloon flights using multiple sensors. The attitude determination system is comprised of a 3-axis accelerometer and a sun sensor. The accelerometer is utilized to measure the gravitational acceleration vector of the payload in the payload's body frame. The measured acceleration vector is based upon the accelerometer's bias and sensitivity which can be found through calibration under zero motion conditions. The sun sensor is comprised of many solar cells at various angles. These are utilized to obtain an accurate sunlight directional vector of the payload in the payload's body frame from an over-determined system of measurement equations. The development of these equations is discussed. Both the gravitational acceleration vector and the sunlight directional vector can also be measured in an inertial frame. It is assumed that these measurements are known a-priori. This provides enough information to solve for an attitude at each sample instance, utilizing two independent vector measurements (i.e., the sunlight and acceleration vectors). The attitude determination system utilizes Markley's solution to Wahba's problem. A 3-axis rate gyroscope is also utilized to gather angular velocity information of the payload in the payload's body frame and was used to compare against angular velocity derived from the estimated attitude to validate the accuracy of the attitude determination system. The measured angular velocity vector is based upon the rate gyroscope's bias and sensitivity which can be found through calibration under zero motion conditions.

How to Cite:

Jain, A. & Isenberg, D. R., (2014) “A Low-Cost Attitude Determination System using Multiple Sensors for High-Altitude Balloon Flights”, Academic High Altitude Conference 2014(1). doi: https://doi.org//ahac.8157