Attitude Updating Algorithm Based on Agile Micro-Nano Satellites

The high dynamic characteristics of agile micro-nano satellites will introduce noncommutativity error in the attitude updating process. Therefore, the attitude updating algorithm of the traditional micro-nano satellite is no longer applicable. This paper proposes a modified attitude updating scheme applied to agile satellites. The method adopts the coning motion as the research scene, in which the influence of noncommutativity error is the worst. Firstly, traditional attitude updating algorithm is presented, and based on the shortcoming of the algorithm, the rotation vector algorithm is introduced. Then, combined with the agile micro-nano satellite's characteristics, the upper bound and lower bound of the algorithm's sampling number are given. Besides, referring to the least-squares algorithm, we carry out angular velocity fitting and calculate the required equal interval angular velocity. Finally, the rotation vector compensation algorithm is derived to gain the updating attitude. The proposed algorithm does not need equal interval angular velocity sampling and can achieve higher estimation accuracy in a dynamic environment than the traditional algorithms. The simulation results validate the effectiveness of the proposed scheme.