Closed-loop wargaming simulation differ from the more widely known human-in-the-loop wargaming simulation by modeling of human decisions integrated into the simulation. That is, unlike conventional computer-aided war games, the purpose of closed-loop wargaming simulations is not to train users in the decision-making role, but to conduct an in-depth investigation of the complex nature of the target phenomenon being simulated. Thus there is a critical difference regarding the "intended use" of the tool. This difference brings about unique challenges and needs to be managed in various aspects during the development of closed-loop wargaming simulation systems.

In terms of model management and validation, some issues stand out such as managing the complexity of the target phenomenon at the model level, determining and applying the appropriate autonomy level of the models, and aligning model fidelities with validation methods in accordance with the intended use. In terms of software engineering and data management, questions should be answered for simulation big data management, analysis and visualization needs, alignment of different aspects of software architecture (such as modeling of autonomy, batch run capabilities, design of experiments) and flexible capabilities to support these needs by the simulation core. From a project management perspective, predictability problems may be encountered in both daily operations and long-term planning. From the user perspective, stakeholder involvement is important in the adaptation of the tool, which can be considered as an interpreted formal language and is usually not easy to practice without particular training.

In this paper, distinguishing aspects that the project team should focus on during the development of closed-loop war game simulation software are discussed. Based on the authors' experience of a project carried out over a period of more than 5 years, the identification of these problems, alternative and proposed solution methods, and lessons learned are discussed.

Keywords
AGILE SOFTWARE DEVELOPMENT;ARCHITECTURE;COMPUTER GENERATED FORCES;SIMULATIONS;VERIFICATION, VALIDATION AND ACCREDITATION (VV&A)

Additional Keywords
closed-loop simulation, automated wargaming simulation, intended use