author = "Romero, Alessandro Gerling and Souza, Luiz Carlos Gadelha de",
          affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and 
                         {Universidade Federal do ABC (UFABC)}",
                title = "Application of a new optimal factorization of the SDRE method in 
                         the satellite attitude and orbit control system design with 
                         nonlinear dynamics",
            booktitle = "Proceedings...",
                 year = "2019",
                pages = "27--33",
         organization = "Internaitonal Conference on Advances in Satellite and Space 
                         Communications, 11.",
            publisher = "IARA",
             keywords = "nonlinear control, SDRE method, satellite control.",
             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. 
                         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 (not unique) linear 
                         structure having State-Dependent Coefficient (SDC) matrices and 
                         then it minimizes a nonlinear performance index having a 
                         quadratic-like structure. The non uniqueness 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 formulations of the 
                         AOCS do not fulfill the SDRE requirements. In this paper, we 
                         evaluate the factorization options of 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 
                         threeaxis, 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 
  conference-location = "Valencia, Spain",
      conference-year = "24-28 mar.",
             language = "en",
           targetfile = "spacomm_2019_3_10_20010.pdf",
        urlaccessdate = "13 abr. 2021"