From Modular to Distributed Open Architectures: A Unified Decision Framework. Issue 3 (3rd August 2016)

• Record Type: Journal Article
• Authors: Heydari, Babak; Mosleh, Mohsen; Dalili, Kia
• Is Part Of: Systems engineering. Volume 19:Issue 3(2016:May)
• Page Start: 252
• Page End: 266
• Publication Date: 2016-08-03
• Subjects: modularity -- uncertainty -- modular open systems architecture -- MOSA -- ecosystem -- complex adaptive systems -- complex networks -- uncertainty management -- fractionated satellite; Systems engineering -- Periodicals; 620.0011
• DOI: 10.1002/sys.21348
• Languages: English
• ISSNs: 1098-1241

Abstract

ABSTRACT: This paper introduces a conceptual, yet quantifiable, architecture framework by extending the notion of system modularity in its broadest sense. Acknowledging that modularity is not a binary feature and comes in various types and levels, the proposed framework introduces higher levels of modularity that naturally incorporate decentralized architecture on the one hand and autonomy in agents and subsystems on the other. This makes the framework suitable for modularity decisions in Systems of Systems and for analyzing the impact of modularity on broader surrounding ecosystems. The stages of modularity in the proposed framework are naturally aligned with the level of variations and uncertainty in the system and its environment, a relationship that is central to the benefits of modularity. The conceptual framework is complemented with a decision layer that makes it suitable to be used as a computational architecture decision tool to determine the appropriate stage and level of modularity of a system, for a given profile of variations and uncertainties in its environment. We further argue that the fundamental systemic driving forces and trade‐offs of moving from monolithic to distributed architecture are essentially similar to those for moving from integral to modular architectures. The spectrum, in conjunction with the decision layer, could guide system architects when selecting appropriate parameters and building a system‐specific computational tool from a combination of existing tools and techniques. To demonstrate the applicability of the framework, a case for fractionated satellite systems based on a simplified demo of the DARPA F 6 program is presented where the value of transition from a monolithic architecture to a fractionated architecture, as two consecutive levels of modularity in the proposed spectrum, is calculated and ranges of parameters where fractionation increases systems value are determined.