TY  - CHAP
A1  - Hallmann, Marcus
A1  - Heidecker, Ansgar
A1  - Schlotterer, Markus
A1  - Dachwald, Bernd
T1  - GTOC8: results and methods of team 15 DLR
T2  - 26th AAS/AIAA Space Flight Mechanics Meeting, Napa, CA
N2  - This paper describes the results and methods used during the 8th Global Trajectory Optimization Competition (GTOC) of the DLR team. Trajectory optimization is crucial for most of the space missions and usually can be formulated as a global optimization problem. A lot of research has been done to different type of mission problems. The most demanding ones are low thrust transfers with e.g. gravity assist sequences. In that case the optimal control problem is combined with an integer problem. In most of the GTOCs we apply a filtering of the problem based on domain knowledge.
Y1  - 2016
N1  - 26th AAS/AIAA Space Flight Mechanics Meeting, February 14-18, 2016, Napa, California, U.S.A. Napa, CA
ER  - 
TY  - JOUR
A1  - Peloni, Alessandro
A1  - Ceriotti, Matteo
A1  - Dachwald, Bernd
T1  - Solar-sail trajectory design for a multiple near-earth-asteroid rendezvous mission
JF  - Journal of Guidance, Control, and Dynamics
N2  - The scientific interest for near-Earth asteroids as well as the interest in potentially hazardous asteroids from the perspective of planetary defense led the space community to focus on near-Earth asteroid mission studies. A multiple near-Earth asteroid rendezvous mission with close-up observations of several objects can help to improve the characterization of these asteroids. This work explores the design of a solar-sail spacecraft for such a mission, focusing on the search of possible sequences of encounters and the trajectory optimization. This is done in two sequential steps: a sequence search by means of a simplified trajectory model and a set of heuristic rules based on astrodynamics, and a subsequent optimization phase. A shape-based approach for solar sailing has been developed and is used for the first phase. The effectiveness of the proposed approach is demonstrated through a fully optimized multiple near-Earth asteroid rendezvous mission. The results show that it is possible to visit five near-Earth asteroids within 10 years with near-term solar-sail technology.
Y1  - 2016
U6  - http://dx.doi.org/10.2514/1.G000470
SN  - 0731-5090
VL  - 39
IS  - 12
SP  - 2712
EP  - 2724
PB  - AIAA
CY  - Reston, Va.
ER  -