4.3.19.1. Modeling and Simulation
4.3.19.1. Modeling and Simulation
Models and simulations are SE tools used by multiple functional area disciplines during all life-cycle phases. Modeling is essential to aid in understanding complex systems and system interdependencies, and to communicate among team members and stakeholders. Simulation provides a means to explore concepts, system characteristics, and alternatives; open up the trade space; facilitate informed decisions and assess overall system performance.
Modeling and simulation provide:
- Insight into program cost, schedule, performance, and supportability risk
- Understanding of capabilities and the requirements set
- Data to inform program and technical decisions
- Efficient communication and shared understanding among stakeholders about relationships between system requirements and the system being developed, through precise engineering artifacts and traceability of designs to requirements
- Better analysis and understanding of system designs (including system elements and enabling system elements), therefore providing a greater understanding of the reasons for defects and failures at all levels
- Greater efficiencies in design and manufacturing by reducing the time and cost of iterative build/test/fix cycles
- Timely understanding of program impacts of proposed changes
The DoD Acquisition Modeling and Simulation Working Group Systems Engineering Modeling, Simulation, and Analysis Fundamentals (located on the DASD(SE) website) recommends that all programs identify and maintain “a collection of related information, representing all necessary viewpoints on the design, and capturing all relevant system interactions.” The Program Manager and Systems Engineer should consider directing the use of such a collection when planning for the development, use, and application of models, simulations, and analyses on their program. This collected information can help drive consistency and integration among SE and analytical tools, and provide the program with a capability to assess potential design changes as well as system upgrades throughout the life cycle. Figure 4.3.19.1.F1. shows some benefits of using modeling and simulation throughout the acquisition life cycle. This figure is adapted from a 2010 National Defense Industrial Association (NDIA) Systems Engineering Division “Model-Based Engineering (MBE)” study and is used with permission.
Modeling and simulation should take advantage of opportunities for reuse (see DoD Modeling and Simulation Catalog). Models and simulations developed in early acquisition phases may be repurposed for other activities during later phases (e.g., engineering models can be used in training simulations).
Figure 4.3.19.1.F1. Benefits of Using Modeling and Simulation throughout the Acquisition Life Cycle
SE requires use of models and simulations from many disciplines and across a hierarchy of perspectives that range from an engineering/technical level up to the campaign/strategic level in order to effectively analyze requirements, design, cost, schedule, performance, and risk. These models and simulations often exist, but sometimes need to be newly developed, which can be costly. An option for new development is to consider federating existing models and simulations, using any of various interoperability standards, in order to create needed capability. Program Managers and Systems Engineers should consider how to leverage M&S interoperability as they plan for M&S use throughout a program's life cycle. Modeling and simulation is also used to support developmental test and evaluation (DT&E) and operational test and evaluation (OT&E).
Roles, Responsibilities, and Activities
To make effective and appropriate use of modeling and simulation, the Program Manager and Systems Engineer should ensure that planned modeling and simulation activities are:
- Complete and comprehensive, including all efforts anticipated throughout the life cycle, to include planning, development, and acceptance through proper verification, validation, and accreditation (VV&A); (see DAG Chapter 9 Test and Evaluation)
- Reflected in the program’s technical planning (Work Breakdown Structure (WBS), schedules, budgets, Systems Engineering Plan (SEP), and other program documentation; see DAG section 4.3.2. Technical Planning Process)
- Appropriately resourced, including a properly skilled workforce
The Program Manager and Systems Engineer should establish and maintain a repository of all relevant modeling and simulation data products that describe what the system is and does. This repository also should contain descriptive system information that could be used to feed other modeling and simulation efforts. They should ensure that all modeling and simulation products are established, maintained, controlled, and resourced to achieve an efficient and effective acquisition program.
Figure 4.3.19.1.F2 shows some applications of modeling, simulation, and analysis throughout the life cycle.
Figure 4.3.19.1.F2. Various Applications of Modeling and Simulation
The Program Manager and Systems Engineer should ensure that the program’s modeling and simulation activities are coordinated, managed, and controlled such that products are consistent with the system and architecture design at all levels. Modeling and simulation planning should be part of the overall program plan; and should be integrated with it. The program may choose to integrate the modeling and simulation planning details into the program plan or create a separate modeling and simulation planning document. If the documents are separate, the program must ensure the modeling and simulation planning is kept up to date as the program plan adjusts. Program Managers should follow their local modeling and simulation organizations standards for planning managing and controlling such activities.
Models and simulations should be:
- Developed and matured through the life of the program
- Properly managed and controlled as part of the program’s technical baseline
- Developed and documented, to include metadata (see Modeling and Simulation Community of Interest Discovery Metadata Specification (MSC-DMS)) and open systems standards, to maximize opportunity for reuse and repurposing (both within the program and in support of other acquisition efforts)
- Included as part of the technical data package to be transitioned into the next phase of the life cycle or into other efforts
Modeling and modeling artifacts should be evident in the contents of the required program technical reviews and in the baselined technical data needed to support major program reviews and program decisions.
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