Vibrometric investigation of museum artefacts and exhibition-cases under the influence of local traffic by means of magnified motion

The conservation and protection of museum artifacts are pressing concerns today. Not only do earthquakes, but also repeated vibrations - such as those from street and underground traffic - pose significant risks to museum structures, display cases, and especially to the ancient artifacts they house. These vibrations can cause art objects to shift or overturn, potentially resulting in impacts and damage. In response to these concerns, a study and monitoring campaign is undergoing at the National Etruscan Museum of Villa Giulia in Rome. Given the vulnerable and historically-significant nature of the collection, a contactless technique is preferrable and videos were recorded using a smartphone. Subsequently, the recordings were analyzed using the motion magnification methodology to achieve dynamic identification of the artifacts and of their display case. The frequencies of the top of the display case were estimated also by means of contact velocimetric records. The investigations revealed a good correspondence between the frequency values determined with the two methods. Additionally, three different support set ups were considered for the camera tripod: non-isolated, with thermoplastic rubber pads, and with natural rubber pads. The two most dominant frequencies were identified with all the setups, but the use of base pads delivers narrower-base peaks and removes spurious frequencies.