Research Center of Structural Health Monitoring and Prognosis, State Key Lab of Mechanics and Control of Mechanical Structures, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China.
State Key Lab of Digital Manufacturing Equipment and Technology, School of Mechanical Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China.
Sensors (Basel). 2018 Jul 10;18(7):2218. doi: 10.3390/s18072218.
Due to the growing use of composite materials in aircraft structures, Aircraft Smart Composite Skins (ASCSs) which have the capability of impact monitoring for large-scale composite structures need to be developed. However, the impact of an aircraft composite structure is a random transient event that needs to be monitored on-line continuously. Therefore, the sensor network of an ASCS and the corresponding impact monitoring system which needs to be installed on the aircraft as an on-board device must meet the requirements of light weight, low power consumption and high reliability. To achieve this point, an Impact Region Monitor (IRM) based on piezoelectric sensors and guided wave has been proposed and developed. It converts the impact response signals output from piezoelectric sensors into Characteristic Digital Sequences (CDSs), and then uses a simple but efficient impact region localization algorithm to achieve impact monitoring with light weight and low power consumption. However, due to the large number of sensors of ASCS, the realization of lightweight sensor network is still a key problem to realize an applicable ASCS for on-line and continuous impact monitoring. In this paper, three kinds of lightweight piezoelectric sensor networks including continuous series sensor network, continuous parallel sensor network and continuous heterogeneous sensor network are proposed. They can greatly reduce the lead wires of the piezoelectric sensors of ASCS and they can also greatly reduce the monitoring channels of the IRM. Furthermore, the impact region localization methods, which are based on the CDSs and the lightweight sensor networks, are proposed as well so that the lightweight sensor networks can be applied to on-line and continuous impact monitoring of ASCS with a large number of piezoelectric sensors. The lightweight piezoelectric sensor networks and the corresponding impact region localization methods are validated on the composite wing box of an unmanned aerial vehicle. The accuracy rate of impact region localization is higher than 92%.
由于复合材料在飞机结构中的应用越来越多，因此需要开发具有大型复合材料结构冲击监测能力的飞机智能复合蒙皮（ASCS）。然而，飞机复合材料结构的冲击是一个随机的瞬态事件，需要在线连续监测。因此，ASCS 的传感器网络及其相应的冲击监测系统作为机载设备需要安装在飞机上，必须满足重量轻、功耗低和可靠性高的要求。为了实现这一点，已经提出并开发了一种基于压电传感器和导波的冲击区域监测器（IRM）。它将压电传感器输出的冲击响应信号转换为特征数字序列（CDS），然后使用简单但高效的冲击区域定位算法来实现轻量级和低功耗的冲击监测。然而，由于 ASCS 的传感器数量众多，实现轻量级传感器网络仍然是实现适用于在线和连续冲击监测的 ASCS 的关键问题。在本文中，提出了三种包括连续串联传感器网络、连续并行传感器网络和连续异构传感器网络的轻量级压电传感器网络。它们可以大大减少 ASCS 中压电传感器的引线数量，也可以大大减少 IRM 的监测通道。此外，还提出了基于 CDS 和轻量级传感器网络的冲击区域定位方法，以便将轻量级传感器网络应用于具有大量压电传感器的 ASCS 的在线和连续冲击监测。在无人机的复合材料机翼盒上验证了轻量级压电传感器网络和相应的冲击区域定位方法。冲击区域定位的准确率高于 92%。
