First ACT global trajectory optimisation competition: Result found at Alcatel Alenia Space

In the frame of the first ACT competition on global trajectory proposed by ESA {[}1], Alcatel Alenia Space has provided a solution based on an internal optimal control Tool T_31). The method proposed to solve the problem is based on the utilisation of the minimum principle. The necessary condition of optimality for the orbit transfer problem is derived, a boundary problem is formulated and presented. The effort of formulation has been restricted to direct transfers. Finally, a synthesis of the trajectories found in the frame of the competition and after is presented to illustrate the capacity of the method and its limitations. (C) 2007 Elsevier Ltd. All rights reserved.