Realistic Software Cost Estimation for Fractionated Space Systems
A Brown, Ramin Moazeni, BARRY W. BOEHM · 2009
challenges to software cost estimation. The concept is a traditional 'monolithic ' spacecraft is replaced by a cluster of wirelessly interconnected spacecraft modules to create a virtual satellite, delivering capability which is at least equivalent to the monolithic spacecraft. Concurrently, they significantly enhance flexibility and system robustness, and reduce risk throughout the mission life and the spacecraft development cycle. Such systems present real challenges to software cost estimation which arise from both the concept of a Directed System of Systems (DSOS) and the reduced risk which is primarily achievable only through the application of an Incremental Commitment Model (ICM). This paper will briefly introduce a next-generation synthesis of the spiral model and other leading process models into the ICM, which is being piloted or considered for adoption in some parts of Department of Defense (DoD). The ICM emphasizes architecting systems (or DSOSs) to encapsulate subsystems (or systems) undergoing the most rapid change; and architecting the incremental development process by having agile systems engineers handling longer-range change traffic to rebaseline the plans for future increments while largely plandriven teams develop and continuously verify and validate (V&V) the current increment, as is usually required for safe or secure software. One approach being followed for estimating the software development cost of the Fractionated Space Craft Systems of Systems (FSSOS) is based on the Constructive Incremental Commitment Cost Model (COINCOMO) model and its tool which currently implements together in one tool the Constructive Cost Model (COCOMO II), the