Modular Multipoint Vibrometer – 48 Eyes See More

Laser scanning vibrometry is a tried-and-tested tool in product development for measuring vibrations in a fast and non-invasive way, especially when it comes to lightweight structures and on hot and challenging surfaces. But it reaches its limits when transient – or, in other words, time-critical or “fleeting” – moments are to be captured. Impact, such as a door slam for example, and other single-event operations cannot be recorded by means of sequential scanning. Polytec has now developed a multipoint vibrometer that simultaneously measures such non-stationary processes at multiple locations from different viewing directions. The MPV-800 boasts a modular design, so the costs remain manageable even when there is a multitude of measurement locations.

The basic system comprises eight vibrometer channels, eight reference channels (for accelerometers, for instance) and one workstation for data acquisition plus analysis software. It can be expanded as appropriate to include other optical units, resulting in a single vibrometer system with up to 48 channels. Each optical unit comprises one eight-channel interferometer, a shared laser light source and connections for eight fiber heads. A wide range of different measuring tasks can be completed, since the up to 48 fiber heads can be arranged in practically any way.

The multi-sensors can be arranged on a stand, for example, where both amplitude and phase distribution on the surface can be analyzed full field. However, the sensor heads can also be freely arranged in the space around the sample if necessary. The findings obtained in this way often permit a better understanding of transient processes, as data from various directions and locations provide the full picture. If you focus the lasers from three sensors onto a single point, the in plane and normal vibration components can be resolved, so even three-dimensional vibration measurements are possible too. The MPV software supports all tasks and offers plenty of practical features that add convenience to the measurements and ensure a high-test quality.

Contact: Christina Petzhold, Polytec GmbH
info@polytec.de