A Dual-Mode Flexible
Sensor Based on the Combination
of Triboelectric and Piezoresistive Sensing to Simultaneously Monitor
Non-Contact/Contact Pressure
posted on 2023-12-06, 13:35authored byLiangsong Huang, Xiaofei Bu, Peng Zhang, Yuxia Li, Shuo Wang, Zhongkai Zhao, Zhifu Chen, Jiapeng Tan
High-performance flexible sensors have broad application
prospects
in various fields such as robotic skin, intelligent prosthetic hands,
and wearable devices. However, a single sensing type of sensor is
limited by its own type and cannot adapt to different types of application
scenarios. Herein, this paper proposes a dual-mode flexible sensor
based on the combination of triboelectric and piezoresistive sensing
(TRS) to simultaneously monitor noncontact/contact pressure in real
time. In the triboelectric sensing mode, the object proximity distance
can be determined by its voltage and current outputs, and the sharpness
can be further judged by the electrode array. It can realize the accurate
detection of distance within 2 cm of the object proximity distance,
and it can generate a voltage signal of 2.75 V when the minimum proximity
distance of the object is 0.5 cm. In the piezoresistive sensing mode,
the sensing performance is optimized by adding a pyramid microstructure
on the surface of the piezoresistive layer, making its sensitivity
reach −0.1147 kPa at a pressure of 0–6 kPa and having
high dynamic response and stability in repeatability testing. The
combination of the two modes solves the problem of difficulty in accurately
sensing pressure signals and noncontact signals for a single type
of sensor. In practical applications, the system has been used to
identify two states of object proximity and pressure and has shown
ideal performance. This provides strategies and references for further
expanding the application scenarios of flexible sensors and has broad
application prospects in providing stronger human–machine interaction
interfaces.