Flight Test, Modal Analysis, and Model Refinement of the Mir Space Station

Abstract

The results and lessons learned from a space-flight experiment, the Mir Structural Dynamics Experiment, are summarized. One of the main objectives for the experiment was to demonstrate the feasibility of performing on-orbit modal testing on large space structures to extract modal parameters that will be used to correlate mathematical models. On-orbit tests were performed in the Mir-alone and Shuttle-Mir mated configurations, and test data were recorded with a variety of existing and new instrumentation systems. Modal analysis was performed on the collected test data to extract modal parameters, that is, frequencies, damping factors, and mode shapes. Model refinements were performed on the Mir-alone and Shuttle-Mir mated configurations. The design sensitivity approach was used for refinement, which adjusts structural properties to match analytical and test modal parameters. Test and analytical responses were compared to evaluate the model verification process. The results demonstrated that on-orbit modal testing and model refinement for large space structures are feasible within operational constraints.