Periodic Control Applied To The Attitude Control Of The Serpens II Mission
Felipe Coelho1; André Luís da Silva1; José R. Pinheiro1
1 Universidade Federal de Santa Maria
Resumo
The number of small satellite projects has considerably increased in the past years, even more owing to the CubeSat concept which has drawn the attention of several universities and of the industry around the world. Usually, small satellites are design for low-Earth orbit missions and, due to dimensional limitation, low-cost budget and available technologies, these satellites are limited in terms of instrumentation. Considering this scenario, the magnetic control becomes appreciated for attitude control. In this case, electromagnetic devices are used to perform the corrective maneuvers. However, it is well known that the Earths magnetic field is time-varying along the orbit and the interaction between it and the electromagnetic actuators introduces uncertainties and nonlinearities on the system. Effects of this directly hamper the performance of the controller and, in such cases, the system is said underactuated. In order to address this problem, this work aims to consider a periodic control design taking into account the periodicity of the geomagnetic field along several orbits. As for the system, it is considered the SERPENS II satellite model which consists in a 3U CubeSat project conducted by Brazilian universities with international cooperation and sponsorship from the Brazilian Space Agency (AEB in Portuguese). Following the methodology presented in the literature, it is intended to design a periodic and robust controller. Simulation results will consider a simplified model and a more realistic model of the satellite in order to evaluate the viability and robustness of this approach.
Palavras-chave: Attitude Control; Periodic Control; Nonlinear System