Simulation of deployment dynamics of spinning spacecraft

Abstract

The evolution of spacecraft of optimum design and acceptable reliability requires knowledge of in-flight dynamic behavior during configuration changes.Systems having radially telescoping or folded appendages a r e analyzed.Neither system is completely amenable to closed form solution, but analog or digital computer techniques can be applied to specific cases.Digital techniques compare favorably with analog methods for this application.Coriolis effects a r e significant for rapid deployments.Behavior parameters can be related to system geometry in closed form but time histories require iteration.Telescoping systems a r e basically irreversible and folding systems cyclic but both are terminated in practice by latching devices.Solutions of the two basic systems may be rationally extrapolated to evaluate adequately more complex systems.Finally, pertinent test experience is summarized.When centrifugal appendage deployment is concurrent with despin, environmental simulation presents major problems including incorrect ambient gravity.Test methods a r e described with particular attention to gravity compensating techniques.Test results correlate acceptably with analytical predictions; however, it is concluded that analysis and testing should be complementary rather than mutually exclusive.