Evolutionary Scheduler for the Deep Space Network
- Thursday, 01 July 2010
A computer program assists human schedulers in satisfying, to the maximum extent possible, competing demands from multiple spacecraft missions for utilization of the transmitting/receiving Earth stations of NASA’s Deep Space Network. The program embodies a concept of optimal scheduling to attain multiple objectives in the presence of multiple constraints. Optimization of schedules is performed through a selection-and-reproduction process inspired by a biological evolution process. A genome (a representation of design parameters in a genetic algorithm) is encoded such that a subset of the scheduling constraints (e.g., the times when a given spacecraft lies within the field of view of a given antenna) are automatically satisfied. Several fitness functions are formulated to emphasize different aspects of the scheduling problem, and multi-fitness functions are optimized simultaneously by use of multi-objective optimization algorithms.