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Holmes, B.

Publications and source records attributed to Holmes, B..

Sensitivity evaluation of mounting optics using elastomer and bipod flexures

A sensitivity evaluation of mounting 100mm optics using elastomer or bipod flexures was completed to determine the relative effects of geometry, structure, material, thermal and vibration environment as they relate to optical distortion. This paper covers both opto-mechanical designs, as well as analytical results from computer modeling and brassboard tests.

elasomer

Optical path control in the MAM testbed

Future space-based optical interferometers will require control of the optical path delay to accomplish some or all of the three objectives: balancing the optical path in the two arms to within a tolerance corresponding to the coherence length of the star light being observed, modulating the optical path in order to observe the phase of the star light interference fringe, and modulating the path length in order to reduce the effect of cyclic errors in the laser metrology system used to measure the optical path length in the two arms of the interferometer.

optical interferometers optical path MAM testbed M

Optical path control in the MAM testbed

The Micro-Arcsecond Metrology (MAM) experiment is one of a family of ground-based testbeds that will demonstrate critical technologies for SIM, the Space Interferometry Mission.

optical interferometers optical path MAM testbed M

Continuous, Multielement, Hot-Film Transition Gage

Accurate measurement of location where laminar boundary layer undergoes transition to turbulent one serves many purposes in basic aero-dynamic research and developmental testing. Individual gages must be staggered to prevent formation of turbulence at gages downstream. This arrangement precludes accurate measurements of laminar/turbulent transition regions along streamline. Complete understanding of performance, stability, and control of laminar-flow airplane requires knowledge of transition locations on wing surface, empennage surfaces, fuselage, and nacelles. Visual, acoustic, and electronic methods capable of providing this transition information.

Holmes, B.

Design, testing, and delivery of an interactive graphics display subsystem

An interactive graphics display system was designed to be used in locating components on a printed circuit card and outputting data concerning their thermal values. The manner in which this was accomplished in terms of both hardware and software is described. An analysis of the accuracy of this approach is also included.

Holmes, B.