DOE OSTI2016
The genesis for this systematic literature review was to search for industry case studies that could inform a decision of whether or not to support the change process, investment, training, and tools needed to implement an MBSE approach across the engineering enterprise. The question asked was, how the change from a document - based systems engineering approach (DBSE) to a model-based systems engineering approach (MBSE) is justified? The methodology employed for this systematic literature review was to conduct a document search of electronically published case studies by authors from the defense, space, and complex systems product engineering industries. The 67 case studies without metrics mainly attributed success to completeness, consistency, and communication of requirements. The 21 case studies with metrics on cost and schedule primarily attributed success to the ability of an MBSE approach to improve defect prevention strategies. The primary conclusion is that there is a significant advantage to project performance by applying an MBSE approach. An MBSE approach made the engineering processes on a complex system development effort more efficient by improving requirements completeness, consistency, and communication. These were seen in engineering processes involved in requirements management, concept exploration, design reuse, test and qualification, Verification and Validation, and margins analyses. An MBSE approach was most effective at improving defect prevention strategies. The approach was found to enhance the capability to find defects early in the system development life cycle (SDLC), when they could be fixed with less impact and prevented rework in later phases, thus mitigating risks to cost, schedule, and mission. However, if a program only employed an MBSE approach for requirements management, advantages from finding defects early could not be leveraged in later phases, where the savings in cost and schedule from rework prevention is realized. Significant performance success was achieved when the systems engineer (SE) held a leadership role over engineering process es. A number of the case studies addressed a general lack of skilled MBSE engineers as a major hindrance to implementing an MBSE approach successfully.