This study reports next generation optical strain measurement with “strain-sensing smart skin” (S⁴) and a comparison of its performance against the established digital image correlation (DIC) method. S⁴ measures strain-induced shifts in the emission wavelengths of single-wall carbon nanotubes embedded in a thin film on the specimen. The new S⁴ film improves spectral uniformity of the nanotube sensors, avoids the need for annealing at elevated temperatures, and allows for parallel DIC measurements. Noncontact strain maps measured with the S⁴ films and point-wise scanning were directly compared to those from DIC on acrylic, concrete, and aluminum test specimens, including one with subsurface damage. Strain features were more clearly revealed with S⁴ than with DIC. Finite element method simulations also showed closer agreement with S⁴ than with DIC results. These findings highlight the potential of S⁴ strain measurement technology as a promising alternative or complement to existing technologies, especially when accumulated strains must be detected in structures that are not under constant observation.

^{本研究报告了使用“应变感应智能皮肤”(S 4} ) 进行的下一代光学应变测量，并将其性能与已建立的数字图像相关 (DIC) 方法进行了比较。S ⁴测量嵌入样品薄膜中的单壁碳纳米管的发射波长的应变引起的变化。新的 S ⁴薄膜提高了纳米管传感器的光谱均匀性，避免了高温退火的需要，并允许并行 DIC 测量。^{使用 S 4}测量的非接触式应变图薄膜和逐点扫描直接与 DIC 在丙烯酸、混凝土和铝试样上的结果进行了比较，其中包括一个具有亚表面损伤的试样。^{S 4}比DIC更清楚地显示应变特征。有限元法模拟也显示出与 S ⁴的一致性比与 DIC 结果更接近。这些发现突出了 S ⁴应变测量技术作为现有技术的有希望的替代方案或补充的潜力，特别是当必须在非持续观察的结构中检测累积应变时。