Practical considerations on using phase resonance or phase separation techniques in large-scale modal tests

Phase resonance or phase separation techniques are state of the art, and in general the advantages and disadvantages of these techniques relevant for a modal test task seem to be clearly recognised. However, there is a tendency to decide on this subject also on nontechnical aspects. These circumstances may lead to test results that are not fully adequate for an accurate and efficient model updating process. Making reference to sweep measurements and tuned mode measurements obtained from of a modal survey test performed on a large spacecraft structure, the potential of phase separation techniques is assessed and compared with the tuned mode measurements in order to provide reference data for selecting the appropriate technique and to draw practical conclusions for similar testing tasks, especially with respect to test performance and testing time.