@Article{MurciaPiņerosBeviPradMora:2024:OpAeMa,
               author = "Murcia Piņeros, Jhonathan O. and Bevilacqua, Riccardo and Prado, 
                         Antonio Fernando Bertachini de Almeida and Moraes, Rodolpho 
                         Vilhena de",
          affiliation = "{Embry-Riddle Aeronautical University} and {Embry-Riddle 
                         Aeronautical University} and {Instituto Nacional de Pesquisas 
                         Espaciais (INPE)} and {Universidade Federal de S{\~a}o Paulo 
                         (UNIFESP)}",
                title = "Optimizing aerogravity-assisted maneuvers at high atmospheric 
                         altitude above Venus, Earth, and Mars to control heliocentric 
                         orbits",
              journal = "Acta Astronautica",
                 year = "2024",
               volume = "215",
                pages = "333--347",
                month = "Feb.",
             keywords = "Aeroassisted maneuver, Gravity assist, Interplanetary flight, 
                         Nonlinear programming, Optimal control problem, Spaceplane.",
             abstract = "This paper analyzes the change in the heliocentric orbital 
                         elements due to the implementation of aerogravity and powered 
                         aerogravity assist maneuvers. Three cost functions were selected 
                         to maximize the planetocentric latitude, longitude, and velocity 
                         at the end of the atmospheric flight. An optimal control problem 
                         was solved to guide a spaceplane passing above the three inner 
                         planets: Venus, Earth, and Mars. The planets were selected because 
                         they have been relevant for gravity assists, and previous studies 
                         suggest that taking advantage of their atmospheres could increase 
                         the effects of the close approach. The research aims to analyze 
                         the variation in the heliocentric orbital elements of the 
                         trajectories after performing optimal aerogravity-assists and 
                         powered aerogravity-assisted maneuvers at high atmospheric 
                         altitudes. The trajectories were calculated via nonlinear 
                         programming to find the history of the control variables: angle of 
                         attack, bank angle, and thrust. Low-fidelity gravity and 
                         atmosphere models were implemented to evaluate this proof of 
                         concept. The optimization converged for all cases, and results 
                         show that maximization of the longitude increases the duration of 
                         the atmospheric flight, increasing the turning angle by almost 
                         twice the value of a single gravity assist. Furthermore, it 
                         reduces the energy and semimajor axis in half for approach angles 
                         between 20 and 90°, saving more than 10 km/s on propulsion. 
                         Maximizing the velocity with propulsion increases the semimajor 
                         axis by more than 1.1 times the semimajor axis of the respective 
                         planet, and the optimal latitude presents a change in inclination 
                         of more than 1.0°. This maneuver could be applied to collect 
                         atmospheric samples or increase the coverage above the planet of 
                         interest. Those kinds of applications are described at the end of 
                         this paper, including a brief discussion on the maturity of this 
                         technology.",
                  doi = "10.1016/j.actaastro.2023.12.017",
                  url = "http://dx.doi.org/10.1016/j.actaastro.2023.12.017",
                 issn = "0094-5765",
             language = "en",
           targetfile = "1-s2.0-S0094576523006471-main.pdf",
        urlaccessdate = "05 maio 2024"
}