TRANSIENT MULTI-DOF VIBRATION TESTING: ANALYTICAL AND EXPERIMENTAL DATA

The HYDRA facility is a very large 6-Degrees-of-Freedom (DoF) hydraulic shaker located in the European Space Research and Technology Centre of ESA in The Netherlands. It has been recently used as test platform to perform a number of innovative, 6-DoF experimental vibration runs with the aim of assessing more flight-representative ways to dynamically qualify a spacecraft, hence reducing the level of conservatism. This paper focuses on the methodology behind the definition of the injected profiles computed by launcher/spacecraft coupled loads analysis, the performance achieved by HYDRA and its state-of-the-art MIMO control system, how the experimental data compare to the simulation ones, and aims also at defining success criteria for 6-DoF transient testing.