Structural identification and monitoring with low cost MEMS accelerometers

The diffusion of MEMS (Micro Electro-Mechanical Systems) technology allows for the mass production of sensors at a very low price. The production technique is derived form that of Integrated Circuits and, as it is common in the mass electronic industry, the “precise” characteristics of each sensor are known in a statistical sense only since the certification costs for a single device greatly exceeds the manufacturing costs. In this context, this work examines the adoption of low cost, un-calibrated, MEMS accelerometers for the lab-testing and modal identification of a scaled civil structure, highlighting the consequences of uncertainty of the sensor parameters on modal parameters: modal forms and frequency estimated for the structure with a non parametric Frequency Domain Decomposition technique.