Xu Chunying, Chen Jiawang, Zhu Huangchao, Zhang Peihao, Ren Ziqiang, Zhu Hai, Lin Yuan
Ocean Collage, Zhejiang University, Zhoushan 316021, China.
Rev Sci Instrum. 2018 Aug;89(8):085103. doi: 10.1063/1.5036666.
The monitoring of displacement variation is important for studying the seabed subsidence mechanism. To meet the multi-point measurement requirements for vertical displacement in subsidence monitoring of the seabed surface, a Micro-Electro-Mechanical Systems accelerometer array was designed. By sensing the tilt angles, displacements on the array can be calculated. The subsidence is calculated as the difference in the displacements from the initial values. To improve the accuracy of the displacement calculation, a calibration model of the tilt angle was presented. The model parameters are computed through a least squares estimation method, which is solved by the Levenberg-Marquardt algorithm. Experimental results show that the calibration model performs excellently with the maximum error of tilt angle being less than 1° in the measurement range (-90°, 90°). The displacement measurement accuracy of the array (2.1 m long) is almost less than 1 cm. Thus, the results show a strong agreement between the detected data and actual deformation in the test.
监测位移变化对于研究海床沉降机制至关重要。为满足海床表面沉降监测中垂直位移的多点测量要求，设计了一种微机电系统加速度计阵列。通过感测倾斜角度，可以计算阵列上的位移。沉降量通过与初始值的位移差值来计算。为提高位移计算的准确性，提出了一种倾斜角度校准模型。模型参数通过最小二乘估计方法计算，该方法由列文伯格-马夸特算法求解。实验结果表明，校准模型性能优异，在测量范围（-90°，90°）内倾斜角度的最大误差小于1°。该阵列（长2.1米）的位移测量精度几乎小于1厘米。因此，结果表明检测数据与测试中的实际变形之间具有高度一致性。
