公开(公告)号：US20080255775A1

公开(公告)日：2008-10-16

申请号：US11952936

申请日：2007-12-07

申请人： Shawn J. Beard ,  Bao Liu ,  Fu-Kuo Chang

发明人： Shawn J. Beard ,  Bao Liu ,  Fu-Kuo Chang

IPC分类号： G06F19/00 ,  G06F15/00

CPC分类号： G01N29/041 ,  G01N29/36 ,  G01N29/4463 ,  G01N2291/0427 ,  G01N2291/106

摘要： A method and system of compensating for environmental effect when detecting signals using a structural health monitoring system includes collecting baseline data signals for one or more values of the environmental effect variable from signals transmitted along selected paths between transducers in an array attached to the structure. A threshold is selected based on the baseline data for determining if the signal is detected. Current data signals are collected and matched to the best fit baseline data. The value of the environmental effect variable is determined on the basis of the matching. A signal is detected according to the selected threshold.

摘要翻译： 一种在使用结构健康监测系统检测信号时补偿环境影响的方法和系统包括从附接到结构的阵列中的选择的路径之间沿着选定路径传输的信号收集环境影响变量的一个或多个值的基线数据信号。 基于用于确定是否检测到信号的基线数据来选择阈值。 收集当前数据信号并与最佳拟合基线数据匹配。 根据匹配度确定环境影响变量的值。 根据所选择的阈值检测信号。

公开(公告)号：US20080255778A1

公开(公告)日：2008-10-16

申请号：US12102767

申请日：2008-04-14

申请人： Bao Liu ,  Fu-Kuo Chang ,  Shawn J. Beard ,  Irene Li

发明人： Bao Liu ,  Fu-Kuo Chang ,  Shawn J. Beard ,  Irene Li

IPC分类号： G06F19/00

CPC分类号： G01N29/041 ,  G01N29/36 ,  G01N29/4463 ,  G01N2291/0427 ,  G01N2291/106

摘要： A method useful in structural health monitoring (SHM) systems for detecting damages in metal structures includes extracting the zero-order symmetric and anti-symmetric mode signal components from each of a plurality of current sensor signals of an array of transducers mounted on the structure, matching the extracted signal components with corresponding signal components of a plurality of baseline sensor signals previously detected in the structure, computing respective indices IS0 and IA0 for each of the matched extracted current and baseline signal components based on respective signal energies thereof, and determining the presence of a damage in the structure if either of the indices IS0 and IA0 of a plurality of neighboring sensor paths of the structure is greater than a selected threshold value.

摘要翻译： 在用于检测金属结构中的损伤的结构健康监测（SHM）系统中有用的方法包括从安装在结构上的换能器阵列的多个电流传感器信号中的每一个提取零级对称和反对称模式信号分量， 将所提取的信号分量与先前在结构中检测到的多个基线传感器信号的相应信号分量相匹配，为每个匹配提取的每个匹配提取出的信号分量计算相应的索引I S0和I A0 < 基于其各自的信号能量的电流和基线信号分量，并且如果多个信号中的任何一个索引I 0和I A 0 <0，则确定结构中是否存在损坏 结构的相邻传感器路径大于所选择的阈值。

公开(公告)号：US07809513B2

公开(公告)日：2010-10-05

申请号：US11952936

申请日：2007-12-07

申请人： Shawn J. Beard ,  Bao Liu ,  Fu-Kuo Chang

发明人： Shawn J. Beard ,  Bao Liu ,  Fu-Kuo Chang

IPC分类号： G01N17/00 ,  G01N25/00 ,  G01M19/00 ,  G01D21/00 ,  G01H17/00 ,  G06F19/00 ,  G06F17/40

CPC分类号： G01N29/041 ,  G01N29/36 ,  G01N29/4463 ,  G01N2291/0427 ,  G01N2291/106

摘要： A method and system of compensating for environmental effect when detecting signals using a structural health monitoring system includes collecting baseline data signals for one or more values of the environmental effect variable from signals transmitted along selected paths between transducers in an array attached to the structure. A threshold is selected based on the baseline data for determining if the signal is detected. Current data signals are collected and matched to the best fit baseline data. The value of the environmental effect variable is determined on the basis of the matching. A signal is detected according to the selected threshold.

摘要翻译： 一种在使用结构健康监测系统检测信号时补偿环境影响的方法和系统包括从附接到结构的阵列中的选择的路径之间沿着选定路径传输的信号收集环境影响变量的一个或多个值的基线数据信号。 基于用于确定是否检测到信号的基线数据来选择阈值。 收集当前数据信号并与最佳拟合基线数据匹配。 根据匹配度确定环境影响变量的值。 根据所选择的阈值检测信号。

公开(公告)号：US20090276168A1

公开(公告)日：2009-11-05

申请号：US12432659

申请日：2009-04-29

申请人： Bao Liu ,  Lien Ouyang ,  Shawn J. Beard ,  Irene Li ,  Fu-Kuo Chang

发明人： Bao Liu ,  Lien Ouyang ,  Shawn J. Beard ,  Irene Li ,  Fu-Kuo Chang

IPC分类号： G01N29/14

CPC分类号： G01H1/00

摘要： Methods and apparatuses for detecting fastener loosening. Sensors query a structure at a baseline value of an environment variable, such as temperature, and this baseline signal is stored for later use. Subsequently, users can query the structure remotely and at any time, and the signals from these queries are compared to the stored baseline signal. In some embodiments, an index is calculated, and the system determines that one or more fasteners have come loose if the calculated index exceeds a predetermined threshold value. It is desirable to select a time window within which the query signal is most sensitive to fastener loosening but least sensitive to variations in the environment variable. Accordingly, embodiments of the invention include methods and apparatuses for determining an optimal time window for use in calculating the above described index.

摘要翻译： 用于检测紧固件松动的方法和装置。 传感器以环境变量（如温度）的基准值查询结构，并将此基线信号存储供以后使用。 随后，用户可以在任何时间远程查询结构，并将来自这些查询的信号与存储的基线信号进行比较。 在一些实施例中，计算索引，并且如果所计算的索引超过预定阈值，则系统确定一个或多个紧固件已经松动。 期望选择查询信号对紧固件松动最敏感但对环境变量的变化最不敏感的时间窗。 因此，本发明的实施例包括用于确定用于计算上述索引的最佳时间窗口的方法和装置。

公开(公告)号：US20080255774A1

公开(公告)日：2008-10-16

申请号：US12104354

申请日：2008-04-16

申请人： Bao Liu ,  Shawn J. Beard ,  Fu-Kuo Chang

发明人： Bao Liu ,  Shawn J. Beard ,  Fu-Kuo Chang

IPC分类号： G06F17/18 ,  G06F19/00

CPC分类号： G01N29/041 ,  G01N29/36 ,  G01N29/4463 ,  G01N2291/0427 ,  G01N2291/106

摘要： A method for adjusting signal data detected in a structural health monitoring (SHM) system to compensate for the effects of environmental variables acting thereon includes constructing a baseline data space comprised of sets of signal data. Current signal data sets are collected for comparison to the baseline data space. The collected current signal data sets are amended to best match baseline signal data sets in the baseline data space. A set of indices are computed for comparing the amended current signal data set to the baseline signal data sets. A threshold for detection is determined by outlier detection for the computed indices. A signal in the collected signal data set is determined to be detected on the basis of the threshold. A representation of the detected signal strength is provided on the basis of the computed indices.

摘要翻译： 一种用于调整在结构健康监测（SHM）系统中检测的信号数据以补偿其上作用的环境变量的影响的方法包括构建由信号数据集合组成的基线数据空间。 收集当前信号数据集，以便与基线数据空间进行比较。 所收集的当前信号数据集被修改以最佳地匹配基线数据空间中的基线信号数据集。 计算一组索引，用于将经修改的当前信号数据集与基线信号数据集进行比较。 用于检测的阈值由所计算的索引的异常值检测确定。 确定收集的信号数据组中的信号根据该阈值进行检测。 基于计算出的索引提供检测信号强度的表示。

公开(公告)号：US08229680B2

公开(公告)日：2012-07-24

申请号：US12432659

申请日：2009-04-29

申请人： Bao Liu ,  Lien Ouyang ,  Shawn J. Beard ,  Irene Li ,  Fu-Kuo Chang

发明人： Bao Liu ,  Lien Ouyang ,  Shawn J. Beard ,  Irene Li ,  Fu-Kuo Chang

IPC分类号： G01N29/14

CPC分类号： G01H1/00

摘要： Methods and apparatuses for detecting fastener loosening. Sensors query a structure at a baseline value of an environment variable, such as temperature, and this baseline signal is stored for later use. Subsequently, users can query the structure remotely and at any time, and the signals from these queries are compared to the stored baseline signal. In some embodiments, an index is calculated, and the system determines that one or more fasteners have come loose if the calculated index exceeds a predetermined threshold value. It is desirable to select a time window within which the query signal is most sensitive to fastener loosening but least sensitive to variations in the environment variable. Accordingly, embodiments of the invention include methods and apparatuses for determining an optimal time window for use in calculating the above described index.

摘要翻译： 用于检测紧固件松动的方法和装置。 传感器以环境变量（如温度）的基准值查询结构，并将此基线信号存储供以后使用。 随后，用户可以在任何时间远程查询结构，并将来自这些查询的信号与存储的基线信号进行比较。 在一些实施例中，计算索引，并且如果所计算的索引超过预定阈值，则系统确定一个或多个紧固件已经松动。 期望选择查询信号对紧固件松动最敏感但对环境变量的变化最不敏感的时间窗。 因此，本发明的实施例包括用于确定用于计算上述索引的最佳时间窗口的方法和装置。

公开(公告)号：US08036836B2

公开(公告)日：2011-10-11

申请号：US12104354

申请日：2008-04-16

申请人： Bao Liu ,  Shawn J. Beard ,  Fu-Kuo Chang

发明人： Bao Liu ,  Shawn J. Beard ,  Fu-Kuo Chang

IPC分类号： G01B3/00

CPC分类号： G01N29/041 ,  G01N29/36 ,  G01N29/4463 ,  G01N2291/0427 ,  G01N2291/106

摘要： A method for adjusting signal data detected in a structural health monitoring (SHM) system to compensate for the effects of environmental variables acting thereon includes constructing a baseline data space comprised of sets of signal data. Current signal data sets are collected for comparison to the baseline data space. The collected current signal data sets are amended to best match baseline signal data sets in the baseline data space. A set of indices are computed for comparing the amended current signal data set to the baseline signal data sets. A threshold for detection is determined by outlier detection for the computed indices. A signal in the collected signal data set is determined to be detected on the basis of the threshold. A representation of the detected signal strength is provided on the basis of the computed indices.

摘要翻译： 一种用于调整在结构健康监测（SHM）系统中检测的信号数据以补偿其上作用的环境变量的影响的方法包括构建由信号数据集合组成的基线数据空间。 收集当前信号数据集，以便与基线数据空间进行比较。 所收集的当前信号数据集被修改以最佳地匹配基线数据空间中的基线信号数据集。 计算一组索引，用于将经修改的当前信号数据集与基线信号数据集进行比较。 用于检测的阈值由所计算的索引的异常值检测确定。 确定收集的信号数据组中的信号根据该阈值进行检测。 基于计算出的索引提供检测信号强度的表示。

公开(公告)号：US08521444B2

公开(公告)日：2013-08-27

申请号：US12856511

申请日：2010-08-13

申请人： Sourav Banerjee ,  Xinlin Qing ,  Shawn J. Beard ,  Fu-Kuo Chang

发明人： Sourav Banerjee ,  Xinlin Qing ,  Shawn J. Beard ,  Fu-Kuo Chang

IPC分类号： G01B3/44

CPC分类号： G01M5/0033 ,  G01M5/0066 ,  G01M5/0083 ,  G06K9/6215 ,  G06K9/6226

摘要： Detecting damage in a structure without comparing sensor signals to a baseline signal. Once a structure is interrogated, a process based on a Gaussian Mixture Model is applied to the resulting data set, resulting in quantities for which Mahalanobis distances and Euclidian distances can be determined. A damage index is then determined based on the calculated Euclidian distance. A high value of this damage index coupled with an abrupt change in Mahalanobis distance has been found to be a reliable indicator of damage. Other embodiments may employ a baseline, but determine damage according to ratios of energy values between current and baseline signals.

摘要翻译： 检测结构中的损伤，而不将传感器信号与基线信号进行比较。 一旦询问结构，将基于高斯混合模型的过程应用于所得到的数据集，导致可以确定马哈拉诺比斯距离和欧几里得距离的量。 然后根据计算的欧几里德距离确定损伤指数。 这种损伤指数的高值与马哈拉诺比斯距离的突然变化已经被发现是损害的可靠指标。 其他实施例可以使用基线，但是根据电流和基线信号之间的能量值的比率确定损坏。

公开(公告)号：US20110040496A1

公开(公告)日：2011-02-17

申请号：US12856511

申请日：2010-08-13

申请人： Sourav BANERJEE ,  Xinlin Qing ,  Shawn J. Beard ,  Fu-Kuo Chang

发明人： Sourav BANERJEE ,  Xinlin Qing ,  Shawn J. Beard ,  Fu-Kuo Chang

IPC分类号： G06F19/00 ,  G06F17/10

CPC分类号： G01M5/0033 ,  G01M5/0066 ,  G01M5/0083 ,  G06K9/6215 ,  G06K9/6226

摘要： Detecting damage in a structure without comparing sensor signals to a baseline signal. Once a structure is interrogated, a process based on a Gaussian Mixture Model is applied to the resulting data set, resulting in quantities for which Mahalanobis distances and Euclidian distances can be determined. A damage index is then determined based on the calculated Euclidian distance. A high value of this damage index coupled with an abrupt change in Mahalanobis distance has been found to be a reliable indicator of damage. Other embodiments may employ a baseline, but determine damage according to ratios of energy values between current and baseline signals.

摘要翻译： 检测结构中的损伤，而不将传感器信号与基线信号进行比较。 一旦询问结构，将基于高斯混合模型的过程应用于所得到的数据集，导致可以确定马哈拉诺比斯距离和欧几里得距离的量。 然后根据计算的欧几里德距离确定损伤指数。 这种损伤指数的高值与马哈拉诺比斯距离的突然变化已经被发现是损害的可靠指标。 其他实施例可以使用基线，但是根据电流和基线信号之间的能量值的比率确定损坏。

公开(公告)号：US08306779B2

公开(公告)日：2012-11-06

申请号：US12039582

申请日：2008-02-28

申请人： Shawn J. Beard ,  Fu-Kuo Chang

发明人： Shawn J. Beard ,  Fu-Kuo Chang

IPC分类号： G06F17/18 ,  G06F11/00

CPC分类号： G01N29/041 ,  G01N29/36 ,  G01N29/4463 ,  G01N2291/0427 ,  G01N2291/106

摘要： Predicting the probability of detection of major and minor defects in a structure includes simulating a plurality of N defects at random locations in a region specified by an array of transducers. Defect size is incremented until it intersects one path between two transducers. The defect size is again incremented until it intersects two or more adjacent paths between pairs of transducers. The number of major defects up to a selected size is determined by the total number of single path intersections by defects up to the selected size. The number of minor defects up to a selected size is determined on the basis of the total number of defects intersecting two or more paths up to the selected size. The probability of detection up to a selected size is the cumulative number of major or minor defects up to the selected size normalizing by N.

摘要翻译： 预测结构中主要和次要缺陷的检测概率包括在由换能器阵列指定的区域中的随机位置模拟多个N个缺陷。 缺陷尺寸递增，直到它与两个换能器之间的一条路径相交。 缺陷尺寸再次递增，直到其与换能器对之间的两个或更多个相邻路径相交。 直到所选尺寸的主要缺陷的数量由直到所选尺寸的缺陷的单路径交叉点的总数来确定。 基于与直到所选尺寸相交的两条或多条路径相交的缺陷的总数来确定直到所选尺寸的小缺陷的数量。 检测到所选大小的概率是直到所选尺寸归一化的主要或次要缺陷的累积数量。