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Massimiliano Vasile

Publications and source records attributed to Massimiliano Vasile.

3 recordsLinked to original sources

Robust mission design through evidence theory and multiagent collaborative search.

In this paper, the preliminary design of a space mission is approached by introducing uncertainties on the design parameters and formulating the resulting reliable design problem as a multiobjective optimization problem. Uncertainties are modelled through evidence theory and the belief, or credibility, that the successful achievement of mission goals is maximized along with the reliability of constraint satisfaction. The multiobjective optimization problem is solved through a novel algorithm based on the collaboration of a population of agents in search for the set of highly reliable solutions. Two typical problems in mission analysis are used to illustrate the proposed methodology.

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Earth-to-Moon low energy transfers targeting L1 hyperbolic transit orbits.

In the frame of the lunar exploration, numerous future space missions will require maximization of payload mass, and simultaneously achieving reasonable transfer times. To fulfill this request, low energy non-Keplerian orbits could be used to reach the Moon instead of high energetic transfers. The low energy solutions can be separated into two main categories depending on the nature of the trajectory approaching the Moon: low energy transit orbits that approach the Moon from the interior equilibrium point L(1) and weak stability boundary transfers that reach the Moon after passing through L(2). This paper proposes an alternative way to exploit the opportunities offered by L(1) transit orbits for the design of Earth-Moon transfers. First, in a neighborhood of the L(1) point, the three-body dynamics is linearized and written in normal form; then the entire family of nonlinear transit orbits is obtained by selecting the appropriate nontrivial amplitudes associated with the hyperbolic part. The L(1)-Earth arc is close to a 5:2 resonant orbit with the Moon, whose perturbations cause the apogee to rise. In a second step, two selected low altitude parking orbits around the Earth and the Moon are linked with the transit orbit by means of two three-body Lambert arcs, solutions of two two-point boundary value problems. The resulting Earth-to-Moon trajectories prove to be very efficient in the Moon captured arc and save approximately 100 m/sec in Deltav cost when compared to the Hohmann transfer. Furthermore, such solutions demonstrate that Moon capture could be obtained in the frame of the Earth-Moon R3BP neglecting the presence of the Sun.

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A systematic-heuristic approach for space trajectory design.

In this paper a novel algorithm is proposed for space trajectory design that combines a systematic and a heuristic method for global optimization. For the systematic part of the algorithm a branching technique is used, whereas a particular implementation of evolution programming forms the core of the heuristic part. The idea is to use a limited population evolving for a small number of generations, according to specific evolution rules, in subregions of the solution space defined by a branching procedure. On the other hand the branching rules are functions of the outcome from the evolution optimization. The proposed combined systematic-heuristic global optimization performs quite well on the cases analyzed in this paper, suggesting the possibility of more complex applications.

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