Evaluation Of Multisensory MEMS-based Accelerometers for Real-time Structural Dynamic Response

Abstract

Due to advancement in sensing technology and IoT in the last few decades, Intrusion Detection System (IDS) and vibration-based health monitoring of infrastructure (SHM) techniques have gain relevance in structure integrity and safety assessment. While complicate instrumentation and high cost are the major obstructing factors for broad adoption. Right now, SHM is just available for strategically important structures. Therefore, research industry has been working on development of techniques to minimize multipurpose system costs and increase both practicality such as multisensory, wireless, mobile, distributed, smart, remote, and diverse detection mechanisms. Smartphones having processing power and standalone power supply with multiple integrated sensors, stand out for their potential as SHM module due to the combination of their attractive hardware and software environment. They can create a smart and participative sensor network of numerous structures using their ability to communicate with the web. Such decentralized and self-governing SHM structure established up by crowdsourcing power supplied by people may also be adhered to even by extremely limited resources in terms of equipment and manpower. How engagement of these smart gadgets in SHM framework will bring several challenges along with many opportunities for public to become involved. In public-initiated SHM scenario, administration has little or no control on sensor instrumentation and operating schedules, and the gathered data is susceptible to alter based on the measurement circumstances. As a result of the sensor setup relying on smartphone user's choices and behaviors, mistakes might arise from configurational errors as well as lack of knowledge in geographical, temporal, and directional uncertainty. Moreover, there is a possibility the smartphone carrying user and as a result, vibration properties detected by smartphones may be altered owing to the human biological system. Some old technology smartphone sensors, on the other hand, have a lower quality and are prone to higher noise levels than traditional high-fidelity sensors. To address such uncertainties there are many problems yet to be solve, an in-depth study should be carried out for behavior of sensor studied and evaluate under different testing facilities and decide for acceptable errors. In this dissertation we will test validate and evaluate smartphone-based Micro electromechanical (MEMS) accelerometer for low cost and user-friendly SHM approach. From current analysis we determine that the proposed sensor is extremely suitable for monitoring earthquakes effects. According to the evaluations conducted in this study these accelerometers may be used as an accelerographer for vibration-based health monitoring of structure. Sensors were tested for wide frequency bands under different testing facility. As per results MEMS-based technology incorporated in these sensor produces minimal levels of self- noise. Nevertheless, this flat behavior is predicted to remain consistent up to the MEMS accelerometer's resonant frequency, which is far higher than the frequency bandwidth of concern to structural earthquake engineers and seismologist in terms of absolute value. In the clipping tests, amplitude linearity of the relation between the output versus input of the system can be represented using modest values up roll-off level. The sensor's strong performance ensures a constant sampling rate even when used for extended periods of time. Using a shake table to simulate a broad array real frequencies from a unique frequency earthquake, the sensor's performance was ultimately evaluated while dealing with non-stationary signals. Many standard earthquake engineering intensity & effects measurements, commonly include horizontal spectrum acceleration and peak transient response.