@InProceedings{RomeroSouz:2019:OpFaSt,
author = "Romero, Alessandro Gerling and Souza, Luiz Carlos Gadelha de",
affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and
{Universidade Federal do ABC (UFABC)}",
title = "Optimal factorization of the state-dependent Riccati equation
technique in a satellite attitude and orbit control system",
year = "2019",
organization = "International Conference on Structural Engineering Dynamics",
abstract = "The satellite attitude and orbit control system (AOCS) can be
designed with success by linear control theory if the satellite
has slow angular motions and small attitude maneuver. However, for
large and fast maneuvers, the linearized models are not able to
represent all the perturbations due to the effects of the
nonlinear terms present in the dynamics and in the actuators
(e.g., saturation). Therefore, in such cases, it is expected that
nonlinear control techniques yield better performance than the
linear control techniques. One candidate technique for the design
of AOCS control law under a large maneuver is the State-Dependent
Riccati Equation (SDRE). SDRE entails factorization (that is,
parameterization) of the nonlinear dynamics into the state vector
and the product of a matrix-valued function that depends on the
state itself. In doing so, SDRE brings the nonlinear system to a
(nonunique) linear structure having state-dependent coefficient
(SDC) matrices and then it minimizes a nonlinear performance index
having a quadratic-like structure. The nonuniqueness of the SDC
matrices creates extra degrees of freedom, which can be used to
enhance controller performance, however, it poses challenges since
not all SDC matrices fulfill the SDRE requirements. Moreover,
regarding the satellite's kinematics, there is a plethora of
options, e.g., Euler angles, Gibbs vector, modified Rodrigues
parameters (MRPs), quaternions, etc. Once again, some kinematics
formulation of the AOCS do not fulfill the SDRE requirements. In
this paper, we evaluate the factorization options (SDC matrices)
for the AOCS exploring the requirements of the SDRE technique.
Considering a Brazilian National Institute for Space Research
(INPE) typical mission, in which the AOCS must stabilize a
satellite in three-axis, the application of the SDRE technique
equipped with the optimal SDC matrices can yield gains in the
missions. The initial results show that MRPs for kinematics
provides an optimal SDC matrix.",
conference-location = "Viana do Castelo, Portugal",
conference-year = "24-26 June",
language = "en",
urlaccessdate = "23 abr. 2024"
}