The Ørsted Satellite Project

Jung, H. (1), and M.L. Psiaki (1)

1. Cornell University, Silbley School of Mechanical & Aerospace Engineering, 226 Upson Hall, Ithaca, NY 14853-7501, USA, Phone: 607 225 8424. E-mail: hj32@cornell.edu

Abstract. A magnetometer-based orbit determination batch filter has been improved and tested with real flight data from Dynamics Explorer 2 (DE-2), and Magnetic Field Satellite (MAGSAT), and the Ørsted satellite. These tests have been conducted in order to determine the performance of a low-cost autonomous orbit determination system. The spacecraft's orbit, magnetometer biases, and correction terms to the Earth's magnetic field are estimated by this filter. Synthesized sun-sensor data in addition to real magnetometer data is used in order to make the field model correction terms observable. The filter improvements include a new dynamics model and consideration of a priori variances for the field model corrections. The best performance that has been achieved with this filter is a maximum position error of 4.48 km for a 2-day batch of DE-2 data with 2nd order/degree field model corrections and 2.35 km for a 24-hour batch of MAGSAT data with 2nd order/degree field model corrections. The maximum position error for a 24-hour batch of Ørsted data is 59.50 km without field model corrections, but is only 2.19 km with 10th order/degree field model corrections.