Development of Wireless Sensors for Shake Table and Full Scale Testing and Health Monitoring of Structures

Abstract

At IZIIS, within the framework of the SERIES project, two types of wireless sensors have been developed. The first one, the MIMRACS (Micro Integrated Measuring Recording and Communication System) sensor, presents an intelligent self-controlled high integrated GPS/GPRS/WEB based micro processing digital 3D measurement device, with the possibility of power independence suitable for measuring, storing and transferring data at the exact time of their appearance. The MIMRACS has 3 MEMS Model 3028 piezoresistive accelerometers, one for each orthogonal axis, a microprocessor, a 24-bit A/D converter, programmable amplifiers, a programmable trigger, an inclinometer, a gyroscope, GPS/GPRS/GSM modules, Flash memory, USB communication and power supply. The other one, SAWARS (Standalone Wireless Acceleration Recording System), is developed on a similar platform as the MIMRACS, with the difference that it is more compact and lighter, with one Model 3028 piezoresistive accelerometer and a Zigbee module and protocol for wireless communication. Both sensors are suitable for laboratory testing (shake table testing), full scale measurements (ambient and force vibration) and seismic and health monitoring of structures. The MIMRACS sensor may also be used as a standalone seismic station as part of a network for monitoring and recording strong motion data. MIMRACS sensors have been tested in laboratory conditions by shake table—standalone testing and testing on models, while recorded signals are compared to traditional wired accelerometers. The comparison results show very good correlation. In this paper, both wireless sensors are presented in detail, including their hardware and software, as well as a comparison of results from various experimental tests.