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Garcia, N. F.

Publications and source records attributed to Garcia, N. F..

WRAP-RIB antenna technology development

The wrap-rib deployable antenna concept development is based on a combination of hardware development and testing along with extensive supporting analysis. The proof-of-concept hardware models are large in size so they will address the same basic problems associated with the design fabrication, assembly and test as the full-scale systems which were selected to be 100 meters at the beginning of the program. The hardware evaluation program consists of functional performance tests, design verification tests and analytical model verification tests. Functional testing consists of kinematic deployment, mesh management and verification of mechanical packaging efficiencies. Design verification consists of rib contour precision measurement, rib cross-section variation evaluation, rib materials characterizations and manufacturing imperfections assessment. Analytical model verification and refinement include mesh stiffness measurement, rib static and dynamic testing, mass measurement, and rib cross-section characterization. This concept was considered for a number of potential applications that include mobile communications, VLBI, and aircraft surveillance. In fact, baseline system configurations were developed by JPL, using the appropriate wrap-rib antenna, for all three classes of applications.

Freeland, R. E.

Technology requirements for large flexible space structures

Research, test, and demonstration experiments necessary for establishing a data base that will permit construction of large, lightweight flexible space structures meeting on-orbit pointing and surface precesion criteria are discussed. Attention is focused on the wrap-rib proof-of-concept antenna structures developed from technology used on the ATS-6 satellite. The target structure will be up to 150 m in diameter or smaller, operate at RF levels, be amenable to packaging for carriage in the Shuttle bay, be capable of being ground-tested, and permit on-orbit deployment and retraction. Graphite/epoxy has been chosen as the antenna ribs material, and the antenna mesh will be gold-plated Mo wire. A 55-m diam reflector was built as proof-of-concept with ground-test capability. Tests will proceed on components, a model, the entire structure, and in-flight. An analytical model has been formulated to characterize the antenna's thermal behavior. The flight test of the 55-m prototype in-orbit offers the chance to validate the analytical model and characterize the control, mechanical, and thermal characteristics of the antenna configuration.

Wada, B. K.

Wrap-rib antenna concept development overview

The wrap rib antenna design of a parabolic reflector large space antenna is discussed. Cost estimates, design/mission compatibility, deployment sequence, ground based tests, and fabrication are discussed.

Woods, A. A., Jr.

Offset wrap rib antenna concept development

The demonstration of 50 to 150 m, STS compatible, offset antenna technology readiness is reported. Fabrication of a ground and flight testable partial 55 m reflector section and feed support structure is discussed. Reduction to practice through ground test verification is presently contained in the program. Key objectives for the program include the design of a compatible feed support structure and the fabrication and testing of critical components.

Woods, A. A., Jr.