A mechanical filter for FBG accelerometers

Many applications are characterized by very severe environment from the sensors point of view. An example is the railway field, where often the measurement setup is subjected to high voltage and electromagnetic emission. In these work conditions, optical sensors are more suitable than electrical ones due to their characteristics. In this paper, the acceleration measurements are taken into account. Nowadays many optical accelerometers are present on the market. In particular, in this work FBG accelerometers are considered. This kind of sensors is characterized by an undamped resonance that can produce the break of the sensor. One possibility to avoid this problem is to add a damping effect in order to reduce the resonance amplification. In the following section, the method to reproduce a mechanical filter able to increase the damping coefficient of the sensor is presented. Experimental results in laboratory will be discussed, showing the effectiveness of the solution.