fig4

Figure 4. Physical sensing (A) Pressure sensing, Reproduced with permission^[46]. Copyright 2022, Licensee MDPI, Basel, Switzerland; (B-D) Strain sensing, Reproduced with permission^{[127,134,135]}. Copyright 2022, Elsevier Ltd; Copyright 2022, American Chemical Society; Copyright 2021, The Royal Society of Chemistry; (E) Temperature sensing of breath, Reproduced with permission^[138], Copyright 2022, Elsevier Ltd; (F and G) Pulse wave sensing, Reproduced with permission^[145,146], Copyright 2020, Elsevier Ltd; Copyright 2022, Elsevier Ltd. Al: Aluminium; FEP: fluorinated ethylene propylene; MS: elastic melamine sponge; PA: polyamide; PENG: piezoelectric nanogenerator; PET: polyethylene terephthalate; PLA: polylactic acid; SUPS: self-powered ultrasensitive pulse sensor.