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Sun et al. Soft Sci. 2025, 5, 18 https://dx.doi.org/10.20517/ss.2024.77 Page 7 of 26

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capacitance changes, enabling non-contact sensing . Furthermore, temperature and material recognition
can be achieved using thermosensitive materials and triboelectric effects. Thermosensitive materials
integrate temperature-sensitive resistors (e.g., platinum thin films), measuring temperature through
resistance changes. The triboelectric effect occurs when frictional charges are generated upon contact, and
by combining quantum dot light emission (QLED), spectral characteristics can be analyzed to distinguish
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materials (e.g., differences in charge release between metals and plastics) .
Finally, intelligent signal processing is essential. Adaptive intelligent algorithms are employed to eliminate
environmental interferences, such as temperature drift or mechanical vibration noise [54,55] . Pressure,
proximity, temperature, and other signals are fed into neural network models to make integrated decisions
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(e.g., proximity signals trigger pre-grasping, while tactile signals adjust the grasping force) . Data
processing is performed at the sensor level, reducing reliance on central processors and enhancing real-time
performance . This significantly improves the overall performance of skin-inspired sensors.
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In summary, skin-inspired sensors operate through a three-step mechanism: biomimetic structure response
to physical stimuli, multimodal signal conversion and intelligent data processing. This process transforms
mechanical, thermal, and electromagnetic information from the external environment into interpretable
digital signals. The core breakthrough lies in the fusion of “sensation” and “computation”, providing
foundational technological support for the next generation of human-machine interactions and intelligent
devices.

Types of skin-inspired sensors
Skin-inspired sensors are designed to mimic the sensory abilities of human skin and are commonly used in
applications such as electronic skin (e-skin), smart prosthetics, bionic hands, robotic skin, wearable devices,
and multimodal sensing systems. In recent years, sensors have increasingly developed towards
multifunctionality and large-scale arrays. Integrating more functions into a single sensor meets the diverse
measurement needs for various physical factors. The manufacturing of larger-scale sensor arrays is essential
for skin-like functional sensing.

To integrate multiple functions into a single sensor, each type of sensor must exhibit superior performance.
For example, temperature sensors emulate the skin’s ability to sense temperature changes in the
environment or objects. Resistive temperature sensors detect temperature through changes in resistance,
particularly exhibiting high sensitivity in lower temperature ranges. One example involved a resistive
temperature sensor with a thin Pt film deposited on a polyimide (PI) substrate, forming a Pt-based 9-
channel array resistive temperature sensor [Figure 3A]. Resistance temperature detectors (RTDs) measure
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temperature by detecting changes in material resistance, offering high accuracy and stability. These sensors
could detect temperature changes through electrical fields or signals, suitable for flexible and wearable
devices. Lead titanate (PbTiO ) is a commonly used material in RTDs, and the ionic organic hydrogel
3
-1
(PC T N ) with high ionic conductivity (2.7 S·m ) is another sensing material for RTD fabrication with
66.7
100 50
excellent temperature-sensitive properties for dynamic temperature monitoring . Thin-film temperature
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sensors, typically made from conductive thin-film materials (e.g., metal oxides and carbon-based materials),
detect temperature through changes in resistance, offering high sensitivity and ease of skin contact. A novel
micro-three-dimensional (3D) structure with better malleability was designed, which also took advantage of
the fast response of a two-dimensional thin film. The sensor enabled real-time temperature measurement
on-site, offering advantages such as small thermal mass and fast response time [Figure 3B].
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