An approximation of the optimal control law for low-thrust transfers between low-eccentricity orbits with small changes of orbital elements is introduced. Transfers with a small number of revolutions around the main body are considered; in this case, Edelbaum's approximation, which is commonly adopted to analyze longer missions, provides unsatisfactory results. The novel approach presented here allows for analytic integration of the differential equations which describe the change of the orbital elements. Numerical solution of an algebraic system provides the control law that is required to obtain the prescribed orbit change. Results for different test cases are shown in comparison to the exact optimal solutions obtained with an indirect method. The mission costs that are evaluated with the approximate control law, provide a very accurate estimation of the actual optima, with a computational cost which is orders of magnitude lower.
Approximate Optimization of Low-Thrust Transfers Between Low-Eccentricity Close Orbits / Casalino, Lorenzo. - In: JOURNAL OF GUIDANCE CONTROL AND DYNAMICS. - ISSN 0731-5090. - STAMPA. - 37:3(2014), pp. 1003-1008. [10.2514/1.62046]
Approximate Optimization of Low-Thrust Transfers Between Low-Eccentricity Close Orbits
CASALINO, LORENZO
2014
Abstract
An approximation of the optimal control law for low-thrust transfers between low-eccentricity orbits with small changes of orbital elements is introduced. Transfers with a small number of revolutions around the main body are considered; in this case, Edelbaum's approximation, which is commonly adopted to analyze longer missions, provides unsatisfactory results. The novel approach presented here allows for analytic integration of the differential equations which describe the change of the orbital elements. Numerical solution of an algebraic system provides the control law that is required to obtain the prescribed orbit change. Results for different test cases are shown in comparison to the exact optimal solutions obtained with an indirect method. The mission costs that are evaluated with the approximate control law, provide a very accurate estimation of the actual optima, with a computational cost which is orders of magnitude lower.Pubblicazioni consigliate
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
https://hdl.handle.net/11583/2542490
Attenzione
Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo