Department of Electrical and Computer Engineering, Southern Methodist University, Dallas, TX 75205, USA.
Department of Civil and Environmental Engineering, Southern Methodist University, Dallas, TX 75205, USA.
Sensors (Basel). 2019 Sep 21;19(19):4083. doi: 10.3390/s19194083.
Accurate three-dimensional displacement measurements of bridges and other structures have received significant attention in recent years. The main challenges of such measurements include the cost and the need for a scalable array of instrumentation. This paper presents a novel Hybrid Inertial Vision-Based Displacement Measurement (HIVBDM) system that can measure three-dimensional structural displacements by using a monocular charge-coupled device (CCD) camera, a stationary calibration target, and an attached tilt sensor. The HIVBDM system does not require the camera to be stationary during the measurements, while the camera movements, i.e., rotations and translations, during the measurement process are compensated by using a stationary calibration target in the field of view (FOV) of the camera. An attached tilt sensor is further used to refine the camera movement compensation, and better infers the global three-dimensional structural displacements. This HIVBDM system is evaluated on both short-term and long-term synthetic static structural displacements, which are conducted in an indoor simulated experimental environment. In the experiments, at a 9.75 m operating distance between the monitoring camera and the structure that is being monitored, the proposed HIVBDM system achieves an average of 1.440 mm Root Mean Square Error (RMSE) on the in-plane structural translations and an average of 2.904 mm RMSE on the out-of-plane structural translations.
近年来，桥梁和其他结构的精确三维位移测量受到了广泛关注。这种测量的主要挑战包括成本和对可扩展仪器阵列的需求。本文提出了一种新颖的基于混合惯性视觉的位移测量（HIVBDM）系统，该系统可以通过使用单目电荷耦合器件（CCD）相机、一个固定的校准目标和一个附加的倾斜传感器来测量三维结构位移。HIVBDM 系统在测量过程中不需要相机保持静止，而相机在测量过程中的运动，即旋转和平移，可以通过在相机视场（FOV）内使用固定的校准目标来补偿。进一步使用附加的倾斜传感器来完善相机运动补偿，并更好地推断全局三维结构位移。在室内模拟实验环境中进行的短期和长期综合静态结构位移实验中对该 HIVBDM 系统进行了评估。在实验中，在监测相机与被监测结构之间的 9.75 米工作距离处，所提出的 HIVBDM 系统在平面内结构平移方面的平均均方根误差（RMSE）为 1.440 毫米，在平面外结构平移方面的平均 RMSE 为 2.904 毫米。
