A Quantitative Methodology for Identifying Evolvable Space Systems

*† With the growing emphasis on spiral development, a system’s ability to evolve is becoming increasingly critical. This is especially true in systems designed for the exploration of space. While returning to the Moon is widely regarded as the next step in space exploration, our journey does not end there. Therefore, the technologies, vehicles, and systems created for near-term lunar missions should be selected and designed with the future in mind. Intelligently selecting evolvable systems requires a method for quantitatively measuring evolvability and a procedure for comparing these measurements. This paper provides a brief discussion of a quantitative methodology for evaluating space system evolvability and an in-depth application of this methodology to an example case study. Nomenclature e = event s = state vector of original mission requirements s’ = state vector of evolved mission requirements S(X) = possible state space of system SL(X) = lawful state space of system W = evolvability vector wi = difficulty rating for i-th state variable along most efficient path of evolvability