Low-Cost Accelerometers for Experimental Modal Analysis

Abstract

The application of Micro-electro-mechanical system (MEMS) based accelerometers has increased exponentially in recent years. It has also experienced an increase in popularity in the structural testing community as they are economical and accurate over large frequency range. Despite the obvious advantages, reservations of using these devices still exist amongst researchers as they are relatively untested. This paper summarises the operating requirements and preferences for using such accelerometers for structural experimental modal analysis. The challenges for adapting MEMS based devices are discussed. The paper presents an interesting example of the application of MEMS based accelerometer for experimental modal analysis of a high rise reinforced concrete building subjected to a series of strong aftershocks. The extracted modal data demonstrated comprehensively that the perceived inaccuracies when using MEMS based devices are in fact well within the standard errors in experiments conducted in a conventional manner.