| dc.description.abstract | Deploying a monitoring system to monitor the health of each bridge cable requires a high cost. Therefore, this research developed a cable monitoring system based on low-power embedded systems and high-precision MEMS sensors. The underlying architecture includes a low-power embedded system, a high-precision MEMS IMU, a high-precision MEMS accelerometer, a 24-bit MEMS ADC, and a LoRa wireless transmission module. First of all, the system will go to sleep mode, when an earthquake occurred, the high-precision IMU will wake up the system for measurement, and it can also be waked up by tapping. The digital MEMS accelerometer on the system has a resolution of 20 Bit, which can be used to measure the acceleration on the steel cable, and the 24-bit ADC with the bridge circuit and strain gauge can be used to measure the strain of the steel cable. In this study, a scaled experimental frame was designed to test the effectiveness of the system. The experimental results show that the measured acceleration of the steel cable can estimate the cable force via FFT analysis. Compared with the real force, the error of estimated force is within 5%, and the estimated value has an excellent linear relationship with the actual value. The strain measured by the strain gauge attached to the steel cable also has an excellent linear relationship with the cable force. The experimental results also saw that when one steel cable is missing on the frame, the frequency of the other steel cable has visible change. | en_US |