This paper extends an XML based system of systems simulation framework using DEVS to support hardware-in-the-loop simulations for SoS. A system of systems approach enables the simulation and analysis of multiple complex, independent, and cooperative systems by concentrating on the data transferred among systems. This paper wraps information exchanged among heterogeneous systems in XML to enable receiving systems to correctly parse and interpret the information. A Groundscout robot is deployed as a real agent working cooperatively with virtual agents in a robotic swarm. The DEVS activity concept facilitates communication between the real system and virtual systems in the SoS. A robust threat detection example is provided. Initial performance metrics of the SoS are briefly discussed.