• Electric Propulsion
• low thrust
• manifold
• numerical propagation
• optimization
• perturbations
• three body model
• Trajectory design

Application of electric propulsion as option for planetary and interplanetary
orbit transfers is accompanied with trajectory design implication arising from
the intrinsic characteristics of the produced low thrust. It is inevitable necessary
to invoke some form of numerical integration in order to either compute
or optimize the trajectory.
The topic of electric propulsion application is expanded in this thesis with
an outline of the associated trajectory design complications. The development
of a numerical tool is discussed, where this tool is developed in order to
collect the methods and techniques required for numerical trajectory analysis.
The development is initiated in collaboration with the European Space
Agency in order to ll a gap in availability of dedicated electric propulsion
mission analysis tools.
With the scope to demonstrate the eectiveness and possibilities of novel
and intelligent application of electric propulsion two trajectory design studies
are discussed. The feasibility to apply electric propulsion as the fundamental
technology to design small-spacecraft missions capable of the exploration of
the outer planets is demonstrated. Realistic mass and time budgets are considered
with missions that provide high scientic outcomes. It will be shown
that the high
V budget associated with outer planet missions can be e-
ciently fullled by electric propulsion, maintaining acceptable total mission
durations and spacecraft nal mass.
It is moreover demonstrated that the consideration of dynamical systems
theory applied to three-body models in order to design low energy missions
can benet from electric propulsion employment. Electric propulsion is capable
to provide a precise low-thrust which can be used to connect the stable
and instable low energy manifolds in dierent three-body models in order to
design novel spacecraft trajectories. It will be shown that the stable and instable
invariant manifolds associated with periodic orbits around the libration
points of several Uranus - moon three-body systems can be connected by a
small spacecraft with electric propulsion, in order to develop a complete planetary
tour orbiting ve moons before reaching a stable orbit around Uranus.