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Wang et al. Soft Sci. 2025, 5, 28 https://dx.doi.org/10.20517/ss.2025.11 Page 17 of 29

multi-gradient structural design addressed the manufacturing challenge of balancing high sensitivity and
wide linear range in flexible sensor arrays, offering new ideas for future sensors with even higher sensitivity
and wider detection ranges [Figure 11].

In addition to the aforementioned trade-offs in sensitivity and operating range, the long-term stability and
reliability of flexible sensor arrays in a variety of test environments with high-frequency pressure and
extreme deformations are one of the challenges that researchers should be aware of. In wearable health
monitoring (e.g., pulse, heartbeat) and human-machine interaction scenarios such as haptic feedback,
sensor array is often exposed to harsh conditions such as high-frequency pressure, cyclic loading, and
complex deformation. Such operating environments may lead to fatigue of the sensor layer materials,
fracture of the conductive network, and failure of the microstructure, thus affecting the reliability and
repeatability of the sensing performance. Therefore, most of the work focuses on improving the
performance of sensing arrays under high-frequency dynamic forces and extreme deformations through
strategies such as structural modulation and material optimization. Hu et al. developed a fully bionic E-skin
(FBE-skin) with top-down architecture of magnetized micro-cilia, conductive micro-domes and flexible
electrodes by mimicking the “hair-epidermis-dermis-subcutaneous” layers of human skin. The
electromagnetic induction from micro-cilia allows the FBE-skin to capture dynamic signals with a
[106]
frequency of up to 100 Hz . Zhang et al. proposed a piezoelectric tactile sensor using a rigid-soft hybrid
force-transmission-layer in combination with a soft bottom substrate inspired by finger structure-rigid
skeleton embedded in muscle. Experiments show that this sensor exhibits a super-high sensitivity, wide
[107]
bandwidth of 5-600 Hz and a linear force detection range of 0.009-4.3 N . Both works were inspired by
the structure of human skin, and innovative structures were developed to realize high-frequency dynamic
force responses. Wu et al. developed a facile solvent-replacement strategy to fabricate ethylene glycol (Eg)/
glycerol (Gl)-water binary anti-freezing and anti-drying organohydrogels for ultra-stretchable and sensitive
strain sensing within a wide temperature range. The strain sensor exhibits a relatively wide strain range
(0.5%-950%) even at -18 °C . This work provides new insight into the fabrication of stable, ultra-
[108]
stretchable, and ultrasensitive strain sensors for emerging wearable electronics.

APPLICATIONS OF FLEXIBLE PRESSURE SENSOR ARRAYS
As IoT advances, flexible sensor arrays are gaining attention in healthcare monitoring, human-machine
interaction, intelligent interaction and equipment. So, researchers are exploring more application scenarios
to better apply sensor arrays to real life.

Human health monitoring
Wearable technology integrates flexible sensors onto human skin to monitor health and enhance comfort
and intelligence in daily life. When applied to the feet, these sensor arrays measure the pressure between the
foot’s sole and the floor, crucial for detecting and diagnosing sports injuries. Luo et al. developed a high-
density sensor array used to identify warning signals and compare right/wrong operations during the
process of intubation. When the guide wire gently slides across the epiglottis, each sensor on the designed
array strip that comes into contact with the human tissue is activated from the head of the guide wire to the
tail, inducing strain on the upper sensor pixels and producing signals, showcasing promising adaptation in
the medical field. Tao et al. developed a smart insole system with capacitive pressure sensors and a data
acquisition system . It features a vertically porous dielectric layer and can map foot pressure in various
[21]
states. Li et al. proposed a perception and interaction strategy for a 3D-stacked wearable Electroluminescent
[109]
and Triboelectric device (ETD) . The ETD uses a bottom triboelectric sensor array to obtain tactile
physiological information. After processing and analysis, it triggers selective illumination in the top
electroluminescent array via an external power circuit. Experiments show it can capture physiological