Functionality, complexity, and approaches to assessment of resilience under contrained energy and information

This research, sponsored by the Department of Defense Systems Engineering Research Center, developed a methodology to measure the functionality and complexity of engineered systems in order to assess system resilience. While system functions, functionality, and complexity are widely used concepts in systems engineering, there is significant diversity in their definitions and no unified approach to measurement. This research establishes a method for measuring impacts to functionality in dynamic engineered systems based on changes in kinetic energy. This metric is applied at particular levels of abstraction and system scales, consistent with the established multiscale nature of systems. By measuring system behavior in context with expected scenarios, it is possible to estimate expected functionality or set bounds on a system's maximum functionality.;Functionality and system effectiveness is heavily influenced by the amount of available energy and the information a system has about its environment. A framework is needed for quickly assessing the impact of changes in information in order to drive system architecture and design. This research relates functionality to the information content required to describe a system using principles from information theory and complexity theory.;The theory developed in this research is validated using an aircraft simulation with 2 degrees of freedom, which is used to generate data against a large number of scenarios for several system instantiations. Analysis of the results of this simulation shows consistency with the developed theory and establishes a solid basis for further exploration and application of this research.