# Recent Progress in Pressure Sensors for Wearable Electronics: From Design to Applications
## 4 Applications of Flexible Pressure Sensors  
### Human-Machine Interfaces  
Human-machine interfaces and remote control of robots can be effectively applied in the field of surgery or risky situations [138]. Several companies have produced surgical robots that are already being used to help doctors perform surgery. Until now, these robots are usually used to prevent hand tremor, but it is expected that the interaction between the robot and the surgeon would be possible. High sensitivity is essential for precise information transfer between humans and machines, and for this purpose, the measurement range corresponding to each use should be properly adjusted. Through this application, even when it is difficult for the doctor to physically access the patient, the operation can be remotely performed in the future. In these applications, the pressure sensors are attached to the \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Transduction Mechanism** & **Key Material** & **Fabrication Method** & **Sensitivity** & \begin{tabular}{c} **Detection** \\ **Limit** \\ \end{tabular} & **Response** & **Ref.** \\ \hline \multirow{4}{*}{\begin{tabular}{c} Resistive \\ \end{tabular} } & Microstructured PDMS & \begin{tabular}{c} Mimosa leaf \\ mold-template \\ \end{tabular} & 50.17 kPa\({}^{-1}\) & 10.4 Pa & 20 ms & [47] \\  & PDMS/CNT & Emulsion-template & 0.1113 kPa\({}^{-1}\) & 20 Pa & 100 ms & [19] \\  & Microstructure PDMS & \begin{tabular}{c} Sandpaper \\ mold-template \\ \end{tabular} & 851 kPa\({}^{-1}\) & 34 Pa & 0.15 ms & [49] \\  & CNT coated cotton & Dlp-coating & 144 kPa\({}^{-1}\) & 2 Pa & 24 ms & [45] \\  & FO & Spray-coating & 0.82 kPa\({}^{-1}\) & 7 Pa & 24 ms & [129] \\ \hline \multirow{4}{*}{Capacitive} & PVDF-TFER NF & Electrospining & 2.81 kPa\({}^{-1}\) & & 42 ms & [111] \\  & Porous PDMS & Particle-template & 0.51285 kPa\({}^{-1}\) & - & 200 ms & [67] \\  & Carbon paste/PDMS composite & Particle-template & 1.1 kPa\({}^{-1}\) & 4 Pa & 60 ms & [75] \\  & Porous CNT/Escide composite & Particle-template & 6.42 kPa\({}^{-1}\) & - & 100 ms & [76] \\  & Pyramid structured PDMS & Silicon mold-template & 0.55 kPa\({}^{-1}\) & 3 Pa & - & [136] \\  & Porous pyramid structured PDMS & Silicon mold and & 44.5 kPa\({}^{-1}\) & - & 50 ms & [73] \\ \hline \multirow{4}{*}{Piezoelectric} & PZT film and microstructured PDMS & Silicon mold-template & 31.8 kC/kPa & - & 20 ms & [84] \\  & Graphene/PtO\({}_{3}\) composite & - & 9.4 MPa\({}^{-1}\) & - & 5–7 ms & [82] \\  & Transfered PZT & XeCI excimer laser & 0.018 kPa\({}^{-1}\) & - & 60 ms & [137] \\  & PVDF-BaTiO\({}_{3}\) NF & Electrospining & 0.017 kPa\({}^{-1}\) & - & - & [40] \\ \hline \multirow{4}{*}{Transistor} & Pyramid structured PDMS & Silicon mold-template & 514 kPa\({}^{-1}\) & 10 Pa & 1.8 ms & [98] \\  & ZnO nanosheets and MAPB & - & 0.57 kPa\({}^{-1}\) & 0.5 Pa & - & [31] \\  & Ag NW embedded PDMS & Wrinkled PDMS & 9.9 kPa\({}^{-1}\) & 0.9 Pa & - & [100] \\  & Amorphous Indium-Gallium-Zinc oxide & - & 0.1 kPa\({}^{-1}\) & - & 190 ms & [21] \\ \hline \multirow{4}{*}{\begin{tabular}{c} Triboelectric \\ \end{tabular} } & Microstructured PDMS and & Sandpaper & 0.51 V/Ap & 5 kPa & 450 ms & [105] \\  & CNT/PDMS composite & mold-template & \
\begin{tabular}{c} C. \(\lambda\)r/airair leaf \\ mold-template \\ \end{tabular} & 127.22 mV/Ap & - & - & [106] \\  & Core-shell PDMS ion gel/PVDF-HFP NF &
\begin{tabular}{c} Dual-nozzle \\ electrospinningining \\ \end{tabular} & 0.43 kPa\({}^{-1}\) & 1.5 kPa & - & [108] \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Summary of some pressure sensors and their electrical performances. machine or human body [139; 140]. In general, the sensors are mounted on the parts that have a large degree of deformation such as fingers, elbows, or knees. Moreover, sensors are also usually attached to the part where a large pressure is typically applied, such as the fingertips or soles.