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Automatic releveling of calibration stands for wind tunnel force and moment measurement instrumentationWind tunnel force and moment measuring instrumentation at NASA LaRC are calibrated by applying NIST certified dead loads, to generate forces and moments in three orthogonal axes, in twenty five percent increments, up to full-load and down to no-load in a nine point continuous procedure, using specially built calibration stands. The measuring instruments deflect upon the application of loads. These deflections must be cancelled to minimize loading interactions. The older calibration stands, integrated with AC induction motors, or DC motors, have provisions for manually releveling the loading point after each load. A newer stand, with integrated DC stepper motors, relevels automatically under software control. It was proposed to extend automation to the old stands. An algorithm to control the unwieldy induction motors to relevel a calibration stand, to within two arcseconds of horizontal direction automatically, was developed. The system developed uses coasting prediction and load adaptation in a general type robust stability control configuration with noncoincidental feedback. Automatic releveling cuts the releveling time to approximately half of the time required to do it manually. The principal constraint for shorter times is the time constant of the angular position feedback transducer.
Document ID
19960020790
Document Type
Conference Paper
Authors
Perazza, Manuel Rodriguez
(Puerto Rico Univ. Mayaguez, Puerto Rico)
Date Acquired
August 17, 2013
Publication Date
December 1, 1995
Publication Information
Publication: The 1995 NASA-ODU American Society for Engineering Education (ASEE) Summer Faculty Fellowship Program
Subject Category
Research And Support Facilities (Air)
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

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IDRelationTitle19960020755Analytic PrimaryThe 1995 NASA-ODU American Society for Engineering Education (ASEE) Summer Faculty Fellowship Program
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