design space pruning heuristics and global optimization method for ...

pruning metric must be calculated for each possible asteroid pair in the design space.
While this is not a problem for the small sample problem, it will become computationally
intensive for significantly larger problems.
Second, each pruning metric is still summed over all the legs for each sequence,
but each metric is applied individually, in sequence. Therefore, all of the asteroid
sequences are first ranked as a function of θ wedge , summed over each of the legs. A userdefined
percentage of sequences is then eliminated from the design space. Next, the
remaining sequences are ranked as a function of the optimal phase-free, two-impulse ∆V,
again summed over all the legs. A user-defined percentage of sequences is then
eliminated from the design space. This approach requires less computation time, since
the optimal ∆V needs to be computed for a smaller number of sequences. Figure 29 and
Figure 30 plot the optimal low-thrust final mass as a function of θBwedgeB and optimal
phase-free, two-impulse ∆V, summed over all the legs for each asteroid sequence in the
sample problem.
Final Mass (kg)
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Figure 29: Final mass as a function of θ wedge , summed over all legs for each asteroid sequence
remaining in the small sample problem.
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