A cost-effective means to predict the nutational stability time constant of spin-stabilized satellite

摘要

Energy dissipation measurements in a precessing scale model facilitated the prediction of the divergent time constant for a communication satellite (DFS-3 Kopernikus) during the spin-stabilized third-stage flight of a Delta II launch vehicle. ^Postflight analysis of telemetry data indicates that the actual nutational stability time constant was within 4 percent of the predicted value. ^This paper describes the energy dissipation measurements and calculations which facilitated this prediction: modeling theory, test facility, error analysis, and results. ^Millions of dollars were saved by flying without launch insurance due to a high degree of confidence in the system as a whole and the analysis reported here. ^Furthermore, the productive life of DFS-3 Kopernikus was extended as a result of the accurate prediction of the divergent time constant; knowledge of the nutational characteristics during the third stage flight facilitated conservation of the spacecraft propellant to maintain position and attitude in geosynchronous orbit. ^(Author)