meetings - Space Flight Mechanics Committee

The algorithm is based on finite differences. The novelty of the method is an automated
tuning of the step size perturbation required for the method. This automation guaranties the
best possible solution using these approach without the requirement of user inputs. The
algorithm treats the functions as a black box, which makes it extremely useful when general
and complex problems are considered. This is the case of spacecraft trajectory design
problems and complex optimization systems. An efficient procedure for the automatic
implementation is presented.
9:20 AAS SOURCE: A Matlab-Orientated Tool for Interplanetary Trajectory Global
13-300 Optimization. Fundamentals (Part I)
Arnaud Boutonnet, ESA / ESOC; Waldemar Martens, ESA / ESOC; Johannes
Schoenmaekers, ESA / ESOC
9:40 Break
This is the first part of the presentation of SOURCE, a new MATLAB-based interplanetary
global optimization tool with very short execution times. The fundamentals of the algorithm
are presented: first the matrices generation, which is based on the evaluation and storage of
porkchops representing the solution of Lambert problems. Special attention is given
singularities (pi-transfer, full resonances) and limitations (transfer with not enough transfer
time, DeltaV-GA). Then a series of filters based on matrices manipulations are presented.
Finally the last step based on a pseudo dynamic programming technique is detailed
10:05 AAS SOURCE: A Matlab-orientated Tool for Interplanetary Trajectory Global
13-301 Optimization, Applications (Part II)
Waldemar Martens, ESA / ESOC; Arnaud Boutonnet, ESA / ESOC; Johannes
Schoenmaekers, ESA / ESOC
This is the second part of the presentation of SOURCE, a new MATLAB-oriented
interplanetary global optimization tool with very short execution times. In the first half of
the paper a quasi-local optimization algorithm is discussed. It is based on the same branch
and pruning algorithm as the global optimization stage. In the second half the results of the
application of the tool to two ESA missions are presented: JUICE and Solar Orbiter. The
objective here is to validate whether the new tool can reproduce known trajectories for these
missions, possibly find new options, while reducing the execution time.
10:25 AAS Extremal Control and Guidance Solutions for Orbital Transfer with
13-303 Intermediate Thrust
Dilmurat Azimov, University of Hawaii at Manoa
The variational problem of an extremal transfer of a spacecraft between elliptical orbits via
one or more intermediate-thrust arcs with constant specific impulse in a central Newtonian
field is considered. New analytical solutions for the transfers between two coplanar
elliptical orbits via the Lawden’s one and two intermediate thrust (IT) arcs are obtained.
The results have been compared to the transfers with impulsive thrusts. The analytical
solutions for the transfer problems obtained in this paper are utilized in the derivation of the
guidance laws for motion with IT arc.
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23 rd AAS / AIAA Space Flight Mechanics Meeting