3nd Global Trajectory Optimization Competition Workshop Team 9. F. Jiang, Y. Li, K. Zhu, S. Gong, H. Baoyin, J. Li, etc. School of Aerospace Tsinghua University Beijing, China. Outline. Team Composition Problem Summary Technical Approach Sequence Selection Global Optimization
F. Jiang, Y. Li, K. Zhu, S. Gong, H. Baoyin, J. Li, etc.
School of Aerospace Tsinghua University
Where mi and mf are the initial and final mass, respectively; K=0.2;
=10; is the stay-time at the j-th asteroid.
SunTechnical Approach: Sequence Selection(2)
Asteroid i moves faster than asteroid j by (i, j) degrees per year, while its initial phase lags that of asteroid j by (j, i) degrees.
By computing the synodic times of potential sequences, no one satisfies absolutely.
We select some sequences with a little inconsistent synodic times, such as 88-76-49.
Conversion from classical orbit elements:
Though more complicated Cartesian quantities, they are more efficient
Choose N particles with random initial position xi0 and velocity vi0. The
iteration from the G generation to G+1 generation can be presented as
where r1 and r2 are both uniformly distributed random numbers; w, c1 and
c2 should be valued case to case.
where F1 and F2 are weighing factors in [0, 1]; the integers rk (k=1,…,5) are
chosen randomly in [1, N] and should be different from i; Index n is a
randomly chosen integer in [1,D]; Integer L is drawn from [1,D] with the
probability Pr(L>=m)=(CR)m-1, m>0. CR is the crossover constant in [0,1];
Leg 2: From A88 to A76
Leg 1: From the Earth to A88
Leg 4: From A49 to the Earth
Leg 3: From A76 to A49
The trajectory from the Earth to asteroid 88
The trajectory from asteroid 88 to asteroid 76
The trajectory from asteroid 76 to asteroid 49
The trajectory from asteroid 49 to the Earth