Invariant-Manifold, Low-Thrust Transfers to Low Mars Orbits

Paper number

IAC-10.C1.9.1

Author

Dr. Giorgio Mingotti, Technion, I.I.T., Israel

Coauthor

Dr. Francesco Topputo, Politecnico di Milano, Italy

Coauthor

Prof. Franco Bernelli-Zazzera, Politecnico di Milano, Italy

Year

2010

Abstract

This work concerns the exploitation of the intrinsic dynamics arising from $n$-body
models together with the optimal control techniques related to continuous low-thrust
propulsion. The results show that it is possible to obtain accurate high-performance
interplanetary trajectories from both the point of view of mass consumption and flight
time. A method to systematically design Earth-to-Mars transfers is proposed through
the definition of special attainable sets. Low orbits around Mars are reached through
a combination of ballistic and low-thrust stages. Moreover, the Earth escape phase,
the rendez-vous one and the final descending arc are solved at the same time.
Finally, the transfers are optimized within wider dynamical n-body models using a direct
method approach and multiple shooting technique.

In details, the complete concentric four-body Sun-Earth-Mars-Spacecraft system
is subdivided in two classic three-body problems: the Sun--Earth model and the
Sun--Mars one. Within this applicative scenario, the ballistic approach is not suitable:
the necessary condition to define low-energy transfers requires that the invariant tubes
intersect in a finite time. This happens for the Planet-Moon cases, but not for
the Sun-Planet systems of the inner celestial bodies. Only the introduction of the
low-thrust perturbation term in the invariant-manifold technique makes possible to
obtain interplanetary transfers taking advantage of the invariant structure of
the problems. Then, by means of a suitable Poincaré section, the trajectory design
is restricted to the selection of the transit point on this surface. Flown backward,
this initial condition generates a trajectory close to the middle stable and
exterior unstable manifolds of the L2 Lyapunov orbits of the Sun--Earth system;
this trajectory represents the ballistic Earth escape stage of the transfer. Integrated
forward, first an accelerated low-thrust arc that allows the rendez-vous with Mars
and then, a transit, martian capture orbit (through L1 gateway) are achieved.

The spacecraft is assumed to be initially on a circular parking orbit around the
Earth; then an impulsive maneuver provided by the launcher, places the spacecraft onto
a heliocentric trajectory. Low-energy low-thrust transfers to low Mars orbits are studied:
after the launch, the spacecraft can only rely on its low-thrust accelerative propulsion to
encounter Mars; then considering a low-thrust deceleration, a spiral descending trajectory
to the target Mars orbit, according to the mission requirements, is obtained.

Abstract document

IAC-10.C1.9.1.brief.pdf

Manuscript document

IAC-10.C1.9.1.pdf (🔒 authorized access only).

To get the manuscript, please contact IAF Secretariat.