Impact of non-latching booms on a nanosatellite attitude control system

Abstract

The Scintillation Prediction Observations Research Task (SPORT) nanosatellite is being developed in partnership with the National Aeronautics and Space Administration agency and the Brazilian Space Agency, with its launch planned for 2022. Its goal is to collect data to improve our understanding of plasma bubbles and the condition that lead to their formation, helping to predict and mitigate their interference in navigation and communication systems. Therefore, to reach this goal, the satellite has several scientific instruments to perform in-situ measurements, with five of them positioned on four booms. These booms do not have a latching system to lock their position; instead, torsional springs are employed to keep them in the deployed state, holding them against their mechanism's structure. This configuration of torsional spring and collision may lead to vibration with the potential to degrade the Attitude Determination and Control System performance, impacting the whole mission. Motivated by the lack of literature covering the non-latching booms dynamics in satellites, this work proposes a framework based on multibody dynamics to simulate satellites with such booms. It also presents a practical method to acquire experimental data and identify the parameters of the booms' deployment mechanism. Later, this work applies the proposed framework and investigates the impact of non-latching booms on the satellite control system to verify if SPORT is able to complete the maneuver. Therefore, experiments were conducted to calibrate both spring and collision models. The multibody model of the satellite was developed and later validated using commercial software. The method for capturing booms' data and determining the mechanisms' parameters shows a satisfactory performance near the booms' deployment position. The proposed framework to simulate satellites with non-latching booms is applied to the SPORT satellite. Simulations in closed-loop indicate that the booms' influence on the SPORT's control system is negligible and the satellite meets its requirements.