Measurement of Structural Dynamic Behavior Using the Sensor Fusion of GPS and IMU

GPS와 관성센서의 융합에 의한 구조물 동적거동 측정

An experimental study was conducted to demonstrate the validity of a sensor fusion technique combining GPS and IMU (Inertial Measurement Unit) to measure the dynamic displacement of structures. In the GPS measurement, a PPP (Precise Point Positioning) mode utilizing only a set of GPS was employed since a DGPS measurement is not available in such a remote position where offshore structures are commonly installed. Through the sensor fusion technique, we could compensate the shortcomings of each of GPS and IMU. A Kalman Filter was used for the sensor fusion to combine the signals from GPS and IMU, and its results were compared with the results of a laser displacement meter which provided a ground truth data. Finally, it was shown that the present sensor fusion technique gave a fairly accurate result even in the situation that the single use of either GPS or IMU cannot provide a right result at all.