Li Dan, Wang Yang
School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA 30301, USA.
School of Electrical and Computing Engineering, Georgia Institute of Technology, Atlanta, GA 30301, USA.
Sensors (Basel). 2020 Jul 9;20(14):3835. doi: 10.3390/s20143835.
Strain and crack are critical indicators of structural safety. As a novel sensing device, a patch antenna sensor can be utilized to wirelessly estimate structural strain and surface crack growth through resonance frequency shift. The main challenges for the sensor are other effects such as temperature fluctuation that can generate unwanted resonance frequency shift and result in large noise in the measurement. Another challenge for existing designs of patch antenna sensor is the limited interrogation distance. In this research, thermally stable patch antenna sensors are investigated for more reliable measurement. Fabricated on a substrate material with a steady dielectric constant, a new passive (battery-free) patch antenna sensor is designed to improve reliability under temperature fluctuations. In addition, another newly designed dual-mode patch antenna sensor is proposed to achieve a longer interrogation distance. Extensive experiments are conducted to characterize the patch antenna sensor performance, including thermal stability, tensile strain sensing, and emulated crack sensing. The two new patch antenna sensors are demonstrated to be effective in wireless strain and crack measurements and have potential applications in structural health monitoring (SHM).
应变和裂缝是结构安全的关键指标。作为一种新型传感装置，贴片天线传感器可用于通过共振频率偏移无线估计结构应变和表面裂缝扩展。该传感器面临的主要挑战是其他效应，如温度波动，它会产生不必要的共振频率偏移并导致测量中出现较大噪声。贴片天线传感器现有设计的另一个挑战是询问距离有限。在本研究中，对热稳定贴片天线传感器进行了研究，以实现更可靠的测量。一种新的无源（无电池）贴片天线传感器制作在具有稳定介电常数的基板材料上，旨在提高温度波动下的可靠性。此外，还提出了另一种新设计的双模贴片天线传感器，以实现更长的询问距离。进行了广泛的实验来表征贴片天线传感器的性能，包括热稳定性、拉伸应变传感和模拟裂缝传感。这两种新型贴片天线传感器在无线应变和裂缝测量中被证明是有效的，并且在结构健康监测（SHM）中具有潜在应用。
