This paper covers issues related to designing for wheel driven systems. The intent is for managing motion to sub arc-second levels, and for this purpose it is primary for the designer to manage measurement and alignment errors, and to establish repeatability through dimensional control, structural and drive stiffness management, adjustability and error management. In a practical sense, there are very few, if any, fabricators that can machine structural and drive components to sufficiently small decimal places to matter. In fact, coming within 2-3 orders of magnitude of the precision needed is about the best that can be expected. Further, it is incumbent on the design team to develop the servo control system features, correction algorithms and structural features in concert with each other. Telescope designers are generally adept at many of these practices, so the scope of this paper is not that, but is limited to those items that pertain to a precision wheel driven system.
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Marvin F. Campbell, "Wheel drives for large telescopes: save the cost and keep the performance over hydrostatic bearings," Proc. SPIE 9145, Ground-based and Airborne Telescopes V, 91452H (22 July 2014);