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Page 2 of 29 Wang et al. Soft Sci. 2025, 5, 28 https://dx.doi.org/10.20517/ss.2025.11

INTRODUCTION
With the continuous progress of science and technology, sensors, as the core carrier of information
[1]
perception, are profoundly influencing human production and lifestyle in modern society . They can
collect a variety of physical parameters in real-time, such as pressure , temperature , humidity ,
[4]
[2,3]
[5,6]
[7]
sliding , gas , ion [10-12] , etc., and enable interconnectivity between humans and things, as well as between
[8,9]
things, via the Internet . This capability provides precise environmental perception and decision support
[13]
for intelligent systems. Flexible sensors, characterized by bendability, stretchability, lightweight properties,
and biocompatibility, have emerged as a breakthrough in sensing technology innovation and have garnered
significant attention in fields such as intelligent electronics , robotic sensing , and medical health
[14]
[15]
monitoring [16,17] .
As an important branch of flexible sensing, flexible sensor arrays achieve multi-channel distributed
information detection and sensing through the integration of multiple sensitive units. This feature gives
flexible pressure sensor arrays a wider range of applications in human-computer interaction. Examples
include smart skins in aerospace [18-20] , smart sensing in medical and healthcare [21-23] , and smart tactile gloves
in human-machine interactions [24-26] . Despite significant progress in improving device performance through
material optimization, structural design and manufacturing innovations, the preparation of high-density
sensor arrays in a limited space remains a key issue as the number of sensor units and integration density
increase. Secondly, signal crosstalk between adjacent channels of an array and mutual limitations between
array performances are challenges that still need to be addressed [Figure 1].

In light of these challenges, this paper reviews existing research on sensor arrays following a challenge-
strategy logical structure. The first section briefly outlines the recent progress of sensor arrays, including
four types of work mechanisms, material components, structural design, and manufacturing methods. The
second section identifies and discusses current challenges in sensor array research, such as high-density
integration manufacturing challenges, crosstalk problems, and performance limitations. Based on existing
literature, the paper summarizes strategies to address these challenges. The third section reviews the
applications of flexible pressure sensor arrays in human-machine interaction including medical health, and
intelligent equipment. Finally, the review concludes with a summary of future development directions for
flexible sensor arrays.

RECENT ADVANCES OF FLEXIBLE SENSOR ARRAYS
Working mechanism and material components
Flexible sensors are capable of converting mechanical stimuli from the external environment into electrical
signals [40,41] . Common sensing mechanisms primarily include four main forms: piezoelectric, piezoresistive,
capacitive, and triboelectric.

The four primary sensing mechanisms exhibit distinct advantages depending on the application scenario.
Piezoelectric and triboelectric sensors feature low power consumption and can operate in self-powered
modes, particularly suitable for applications that involve dynamic mechanical stimuli, such as motion
monitoring or touch detection . In contrast, piezoresistive sensors are more appropriate for static or slowly
[42]
varying signals, offering better signal stability and long-term durability . The sensitivity and overall
[43]
[44]
performance of each sensor mechanism are influenced by the materials and structural designs employed .
A comparative summary of their key characteristics is provided in Table 1.

Piezoelectric sensors work on the basis of the piezoelectric effect. When a piezoelectric material is subjected
to a force and deforms, electrical charges are generated on its surface, allowing mechanical energy to be