Soft Biomimetic Fiber-Optic Tactile Sensors Capable of Discriminating Temperature and Pressure

A Review of Wearable Optical Fiber Sensors for Rehabilitation Monitoring

“…Shang and colleagues [100] introduced a soft, bio-inspired, fiber optic tactile sensor (SBFT) capable of sensing and differentiating between temperature and pressure akin to human skin, as shown in Figure 3c. The SBFT sensor is constructed by encapsulating a macroscopically curved Fiber Bragg Grating (FBG) within an elastomer droplet, generating two distinct types of optical resonances-FBG-related and whispering gallery modes (WGMs)-which propagate along the curvature.…”

“…Shang and colleagues [ 100 ] introduced a soft, bio-inspired, fiber optic tactile sensor (SBFT) capable of sensing and differentiating between temperature and pressure akin to human skin, as shown in Figure 3 c. The SBFT sensor is constructed by encapsulating a macroscopically curved Fiber Bragg Grating (FBG) within an elastomer droplet, generating two distinct types of optical resonances—FBG-related and whispering gallery modes (WGMs)—which propagate along the curvature. By leveraging the distinct thermo-optical and stress-optical properties of FBG and WGM resonances, the SBFT sensor can fully decouple pressure and temperature measurements, achieving an accuracy of 0.2 °C for temperature and 0.8 mN for pressure.…”

Recent Progress in MEMS Fiber-Optic Fabry–Perot Pressure Sensors

“…Fiber-optic-based sensors [ 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 ], which can overcome the shortcomings of electrical sensors due to the advantages of their anti-electromagnetic interference, flexibility, and corrosion resistance, have received extensive attention from researchers. Common fiber-optic pressure sensors include point type, such as long period grating [ 15 , 16 ], fiber Bragg grating (FBG) [ 17 , 18 , 19 , 20 ], fiber Mach–Zehnder (MZ) interferometer [ 21 , 22 , 23 ], fiber FP interferometer [ 24 ], and so on [ 25 , 26 ]. Among them, the MEMS fiber-optic FP pressure sensor is the focus of researchers thanks to its simple structure, small size, high accuracy, low temperature crosstalk, and resistance to complex environments.…”

AI-Assisted Insole Sensing System for Multifunctional Plantar-Healthcare Applications

“…26 Shang et al developed a soft biomimetic silica optical fiber sensor that offers skin-like tactile sensing abilities to perceive and discriminate temperature and pressure. 27 The sensor is fabricated by encapsulating a macrobent silica fiber Bragg grating (FBG) in an elastomeric droplet-shaped structure, which is capable of perceiving pressure, temperature, and hardness when touching soft tissues and human skin. However, due to the poor stretch performance (tensile strain <1%) and breakage of silica optical fiber, it is not a good candidate for making wearable devices.…”

“…These advantages can effectively compensate for the shortcomings of electrical sensors and will play a huge role in health monitoring and diagnostic treatment systems . Shang et al developed a soft biomimetic silica optical fiber sensor that offers skin-like tactile sensing abilities to perceive and discriminate temperature and pressure . The sensor is fabricated by encapsulating a macrobent silica fiber Bragg grating (FBG) in an elastomeric droplet-shaped structure, which is capable of perceiving pressure, temperature, and hardness when touching soft tissues and human skin.…”