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As the system engineering process flows down constellation coverage specifications to the Spacecraft level in terms of agility requirements it's critical that the relationships between manueverability and cost are clearly understood. The probability of optimizing the cost of typical ATP system would be greatly enhanced if a realistic integrated cost/engineering model were available during the initial phase of a program (e.g. Conceptual Design Phase). Most Cost Engineering work performed to date has been done by Cost and/or Systems Engineers which has typically lead to models with a cost emphasis. This work tends to be parametric in nature and hence the models have has little 'buy-in' from the design engineering side of the house. A better approach is to take existing credible engineering models for the key Spacecraft subsystems (Attitude Control, Thermal, Power, etc.) and to append these models to include the appropriate hardware databases. This would allow the models to output cost, power and weight, besides analytical engineering parameters like torque, momentum, etc.. For sound engineering reasons some, but not all, subsystem models should be time-domain based (dynamic) simulations--a clear diverges from the typical Systems Engineering approach. A modular spacecraft model like the one created at Lockheed for the FEWS/ALARM programs provides an ideal basis for developing a Dynamic Integrated Cost & Engineering (DICE) Model. This paper provides a 'snapshot' of the initial development of Attitude Determination and Control portion of the DICE Model. These subsystems were modeled first since maneuverability has such a large cost impact on them. A multiple body dynamics package, High TEC1, provides the core of this DICE module. This package has been integrated into several simulation packages as described in previous works. Having access to this detailed 3-axis simulation model allows one to properly size spacecraft attitude systems (especially sensors and actuators). Hardware models can be easily interchanged through the friendly Graphical User Interface integrated with High TEC. The DICE Control system module outputs hardware attributes such as type (Reaction Wheels, Control Momentun Gyros, etc.), size, power, cost, etc., as a function of maneuverability. With this tool, Design and Systems Engineering can work together to optimize ATP cost rather than having coverage requirements flown down with little regards to design constraints and capabilities.
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