A Model for Quantifying System Evolvability Based on Excess and Capacity

作者：Tackett Morgan W P; Mattson Christopher A^*; Ferguson Scott M

来源：Journal of Mechanical Design, 2014, 136(5): 051002.

DOI：10.1115/1.4026648

• reconfigurability
• flexibility
• adaptability
• transformation
• evolvability
• service-phase evolution
• system changes
• system space

An important factor in system longevity is service-phase evolvability, which is defined as the ability of a system to physically transform from one configuration to a more desirable configuration while in service. These transformations may or may not be known during the design process, and may or may not be reversible. In a different study, we examined 210 engineered systems and found that system excess and modularity allow a system to evolve while in service. Building on this observation, the present paper introduces mathematical relationships that map a system%26apos;s excess to that system%26apos;s ability to evolve. As introduced in this paper, this relationship is derived from elastic potential-energy theories. The use of the evolvability measure, and other related measures presented herein, are illustrated with simple examples and applied to the design of U. S. Navy nuclear aircraft carriers. Using these relationships, we show that the Navy%26apos;s new Ford-class aircraft carrier is measurably more evolvable than the Nimitz-class carriers. While the ability for systems to evolve is based on excess and modularity, this paper is focused only on excess. The mapping between modularity and evolvability is the focus of another work by the authors.

• 出版日期2014-5