Distributed Vibration Sensor

The distributed vibration sensor measures the deformation of the structure it is attached to. It is a thin piezoelectric foil, transforming the vibration of the structure into an electrical signal. Micromega developed a technology to tailor the piezoelectric constants of the sensor foil in two dimensions. As such the sensor can filter certain structural modes. One single structural mode can be measured, as well as a weighted combination of several (two-dimensional) structural modes. The main advantage is that this modal sensor does not show observation spillover to other structural modes, meaning that other modes are not measured, not even at very high frequencies. This is a requisite to build stable and efficient active vibration control systems.

A typical application of the distributed vibration sensor is the volume velocity sensor. It is a thin piezoelectric foil, attached to a rectangular plate. The piezoelectric constants vary over two dimensions such that the piston-like motion of the panel is measured. This volume velocity mode is responsible for the sound radiation of the panel at low frequencies. With this sensor, the low frequency sound radiation can be measured without observation spillover to higher order modes, such that the design of an active noise control system to reduce the sound transmission through the panel can be built much more efficiently and with improved better.

In addition Micromega developed the technology to build a transparent version of this sensor, such that the distributed vibration sensor can be used on windows.