FORCE-LIMITED VIBRATION TESTING APPROACH APPLIED TO RANDOMVIBRATION TEST OF SOLAR PAYLOAD

摘要

The flexibility of the Columbus Experiment PayloadAdapter (CEPA) significantly influences the RandomVibration Environment (RVE) at SOLAR interface(I/F).Since a random qualification test in hard-mountedcondition was foreseen, the design load factors wouldbe exceeded if the RVE analytically derived at SOLARto CEPA I/F would be directly applied.Therefore, an expressly developed, validatedmethodology has been adopted: based on theequivalence of resultant I/F forces in hard-mounted andsoft-mounted condition (for corresponding mainmodes), notched random spectra have been derived andapplied as test input.During the test activity, significant frequency reductionof the main resonances has been detected, imputable toI/F's non-linearity, while the assumed amplificationfactor was confirmed.Therefore, the analytically defined input spectra havebeen adapted to the real dynamic behaviour.After a successful FEM model correlation activity, theeffective masses computation has confirmed thecorrectness of main resonances identification and theachievement of the foreseen qualification loads.