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Journal of ZheJiang University (Engineering Science)  2022, Vol. 56 Issue (6): 1079-1087, 1126    DOI: 10.3785/j.issn.1008-973X.2022.06.004
High sensitivity flexible tactile sensor with hierarchical tilted micro-pillar structure
Xiao-hui GUO1,2(),Wei-qiang HONG1,Guo-qing ZHENG3,Jing-yi WANG3,Guo-peng TANG1,Jin-yang YANG1,Chao-qiang ZHUO1,Yao-hua XU1,Yu-nong ZHAO4,Hong-wei ZHANG1,*()
1. School of Electronic Information Engineering, Anhui University, Hefei 230601, China
2. Anhui Province Key Laboratory of Target Recognition and Feature Extraction, Lu’an 237010, China
3. East China Institute of Optoelectronic Integrated Devices, Suzhou 215163, China
4. School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan 430074, China
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A flexible tactile sensor was proposed based on the hierarchical titled micro-pillar structure, in order to meet the precise tactile sensing application requirements of capacitive flexible tactile sensors in wearable electronic devices, intelligent robots and other fields. When the sensor was subjected to external pressure, the titled micro-pillar was deformed in stages, resulting in an increase in the capacitance of the sensor. Combined with simulation and experiment, the influence of sensor structure characteristics on its sensitivity were studied, the relationship between sensor signal output and loading pressure designed with different structural parameters was revealed, and the structure of tactile sensor was optimized. The experimental data showed that the sensor had good sensitivity (0.44 kPa?1) and low detection limit (2.6 Pa), the response time was 40 ms, the maximum hysteresis error was 6.7% The sensor exhibits excellent stability and repeatability during 2 400 cycles of loading/unloading, and it can be extended to "skin" arrays of different sizes and shapes, the precise perception of the manipulator and the monitoring of motion postures of the human body were realized.

Key wordselectronic skin      flexible tactile sensor      high sensitivity      rapid response      hierarchical tilted micro-pillar     
Received: 02 March 2022      Published: 30 June 2022
CLC:  TP 212  
Fund:  国家自然科学基金青年基金项目(61901005);安徽省自然科学基金青年基金项目(1908085QF261);中国博士后科学基金资助项目(2021M690994);安徽省博士后研究人员科研活动经费资助项目(2021B539);2021年度安徽省中央引导地方科技发展资金专项项目(202107d08050012)
Corresponding Authors: Hong-wei ZHANG     E-mail:;
Cite this article:

Xiao-hui GUO,Wei-qiang HONG,Guo-qing ZHENG,Jing-yi WANG,Guo-peng TANG,Jin-yang YANG,Chao-qiang ZHUO,Yao-hua XU,Yu-nong ZHAO,Hong-wei ZHANG. High sensitivity flexible tactile sensor with hierarchical tilted micro-pillar structure. Journal of ZheJiang University (Engineering Science), 2022, 56(6): 1079-1087, 1126.

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为了满足电容式柔性触觉传感器在可穿戴电子设备、智能机器人、人机交互等领域的精准触觉感知应用需求,基于分级倾斜微圆柱结构提出柔性触觉传感器.传感器在受到外界压强作用时,引起倾斜微圆柱分级变形,导致传感器电容增大.结合仿真和实验研究传感器结构特征对其灵敏度的影响规律,揭示不同结构参数设计的传感器信号输出与加载压强间的关系,优化触觉传感器结构.实验数据表明,所提传感器具有良好的灵敏度(0.44 kPa?1)和低检测下限(2.6 Pa),响应时间为40 ms,最大迟滞误差为6.7%,在2 400次循环加/卸载过程中展现了优异的重复性和稳定性.该传感器可以拓展为不同尺寸和形状的“皮肤”阵列,实现了机械手精准感知和人体运动姿态监测.

关键词: 电子皮肤,  柔性触觉传感器,  高灵敏度,  快速响应,  分级倾斜微圆柱 
Fig.1 Schematic diagram of structure and composition of 5×5 hierarchical tilted micro-pillar structure unit sensor
Fig.2 Stress distribution simulation of different micro-pillar structures under different pressures
Fig.3 Schematic diagram of preparation process of sensor array
Fig.4 Optimization of structural feature parameters of capacitive tactile sensor
Fig.5 Characteristic testing of sensors
Fig.6 Stability test of sensor during 5 kPa pressure loading/unloading
Fig.7 Capacitive flexible tactile sensor performance comparison
Fig.8 Response signal curve when manipulator grasps objects with different hardness
Fig.9 Experiment of pressure distribution sensing with 8×8 sensor array
Fig.10 Finger touch manipulator integrated sensor experiment
Fig.11 Sensors used in various monitoring applications of different human motion states with proposed sensor
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