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Williams, C. D.

Publications and source records attributed to Williams, C. D..

An evaluation of foldable elastic tubes for application in space structures

An experimental investigation and design study has been performed on one type of foldable elastic tube in order to assess its suitability as a member of deployable space structures. It is demonstrated that one or more slots inserted longitudinally in the center of the tube to alleviate strain serves to prevent collapse of the tube. The nonlinear spring characteristics of the tube that are required for computer-based deployment dynamic analysis of space structures are determined, and it is shown that strain energy levels over a certain range are realizable for tubes representing space structure members in the 15-20 ft length range. Approximate strain energy/geometric parameter relationships are developed which may be useful for preliminary design or concept studies.

Jones, I. W.

Study of foldable elastic tubes for large space structure applications

Various modifications were made to the tube design. The tubes were retested and analyzed, and the results are presented. One type of modified tube, the slotted tube, deployed successfully and reliably, and became the focus of detailed tests. Optimal design criteria, taking into consideration deployment as well as strength and buckling behavior were established.

Jones, I. W.

Study of foldable elastic tubes for large space structure applications, phase 1

Structural members that might be suitable for strain energy deployable structures, are discussed with emphasis on a thin-walled cylindrical tube with a cross-section that is called 'bi-convex'. The design of bi-convex tube test specimens and their fabrication are described as well as the design and construction of a special purpose testing machine to determine the deployment characteristics. The results of the first series of tests were quite mixed, but clearly revealed that since most of the specimens failed to deploy completely, due to a buckling problem, this type of tube requires some modification in order to be viable.

Jones, I. W.