Angular Velocity Estimation for Nanosatellites Using Vector Measurements

  • Halil Ersin Soken Middle East Technical University
Keywords: vector measurements, small satellite, Angular Velocity Estimation

Abstract

In the absence of gyro sensors, the straightforward approach to estimate the angular velocity is using a dynamics-based attitude filter which can provide angular rate information together with the attitude of the satellite. However, this approach requires also the reference directions for the vector measurements. In this article, assuming that the reference directions are not known, two different algorithms for angular velocity estimation, using only the body vector measurements are given and compared. They both rely on pre-filtering the noisy data, specifically for the magnetometer measurements. The first algorithm estimates the Residual Magnetic Moment (RMM) terms along with the angular velocity vector. The second algorithm does not use the spacecraft dynamics and model the angular accelerations as a first-order Markov process. Demonstrations show the first algorithm can provide an accuracy up to 0.035 deg/s for angular velocity estimates and accurately estimate the RMM terms, whereas the second algorithm is a computationally efficient alternate that can be used flexibly at any mission phase.

Published
2021-07-30
How to Cite
[1]
H. Soken, “Angular Velocity Estimation for Nanosatellites Using Vector Measurements”, JAST, vol. 14, no. 2, pp. 221-229, Jul. 2021.
Section
Articles