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The Ultraviolet/Optical/Infrared (UVOIR) flagship astrophysics architectures proposed by the Astro2020 Decadal Survey fundamentally challenge the current test-like-you-fly approach to space systems, because of their physical scale, multiple stages of on-orbit deployment, and extremely stringent optical performance requirements unique to visible-light coronagraphy. These limitations elevate the importance of integrated control, structural dynamics, and optical modeling, particularly in early system architecture studies. A unique non-contact observatory control architecture called Disturbance Free Payload (DFP) for next-generation large astrophysics observatories involves physically isolating the segmented telescope structure from the supporting spacecraft by means of a non-contact interface. In this control architecture, rigidbody telescope pointing is achieved by actuating the payload with non-contact voice coil actuators and maintaining positive interface gaps using spacecraft inertial actuators and interface non-contact sensors. This architecture presents distinct advantages over current state-of-the-art spacecraft vibration isolation approaches, particularly for large flexible spacecraft, but also introduces unique disturbance and coupling mechanisms that must be analyzed. In this paper, development of an integrated model is described, consisting of a 6.7-meter inscribed segmented optical system, and an unobscured telescope with 55 primary mirror segments. The paper starts with an overview of the models that directly predict time-domain lineof-sight and wavefront error dynamic stability (optics, dynamics, control system, error sources). Next, key dynamic stability performance metrics for coronagraph contrast performance are described and a systematic methodology for realizing an accurate but computationally feasible truncated modal model is presented. Finally, an exemplar point design that is compliant to 10-picometer RMS wavefront error is developed, and the necessary component errors to achieve this performance are presented.
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