Variation in the modal parameters of space structuresAn analytic and experimental study of gravity and suspension influences on space structural test articles is presented. A modular test article including deployable, erectable, and rotary modules was assembled in three one- and two-dimensional structures. The two deployable modules utilized cable diagonal bracing rather than rigid cross members; within a bay of one of the deployable modules, the cable preload was adjustable. A friction lock was used on the alpha joint to either allow or prohibit rotary motion. Suspension systems with plunge fundamentals of 1, 2, and 5 Hz were used for ground testing to evaluate the influences of suspension stiffness. Assembly and reassembly testing was performed, as was testing on two separate shipsets at two test sites. Trends and statistical variances in modal parameters are presented as a function of force amplitude, joint preload, reassembly, shipset and suspension. Linear finite element modeling of each structure provided analytical results for 0-g unsuspended and 1-g suspended models, which are correlated with the analytical model.
Document ID
19920051775
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Crawley, Edward F. (NASA Langley Research Center Hampton, VA, United States)
Barlow, Mark S. (NASA Langley Research Center Hampton, VA, United States)
Van Schoor, Marthinus C. (MIT Cambridge, MA, United States)
Bicos, Andrew S. (McDonnell Douglas Space Systems Co. Huntington Beach, CA, United States)
Date Acquired
August 15, 2013
Publication Date
January 1, 1992
Subject Category
Spacecraft Design, Testing And Performance
Report/Patent Number
AIAA PAPER 92-2209
Meeting Information
Meeting: AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference