A flexible electronic control device based on the metallic sensor \”sandwich\” structure of the man-machine airgel

I. Background:

In recent years, flexible wearable strain sensor demonstrate huge advantages and potential applications in human-computer control, flexible robotics and intelligent medical and other fields. However, at present inorganic nanomaterial is applied to the resistive strain sensor facing lower sensitivity, unitary structure, preparation of complex, high cost and other problems, which further development of the flexible wearable sensor device presents new challenges. In addition, based on the manipulation of human body weak signal detection and flexible wearable sensor remains to be further research and development.

Second, the article Introduction:

To solve the above problem, Northwestern Polytechnical University and Nanjing University of Technology Huang academician , Prof. Zhuji Xin (co-author) through an efficient, safe, low-cost synthetic methods, the synthesis to achieve high performance metallic VN / CNTs mixture airgel , relevant results published in Nano Letters , first author doctoral students Zhang Hongjian . The authors have prepared a special class of nano brush sandwich structure and excellent electrical properties VN / CNTs nanomaterials, and combines high sensitivity is designed to apply a slight strain with PDMS flexible substrate, high durability and high response flexible strain sensor velocity and successfully applied to real-time man-machine control system and more human sounding physical signals.

FIG 1. VN / theoretical design principles and synthetic CNTs. (A-b) Design the structure and properties of first-principles calculation. (C-d) and synthetic materials, crystal structure Schematic diagram.

Third, the content of the article:

1, materials design and \”nitride and carbide-step\” synthesis strategies

First, by the first principle calculation methods, structure and electrical properties of VN / CNTs were predicted. The results show VN CNT tend perpendicular to the sheet surface grow a nano-ordered three-dimensional network structure, such a unique structure with goodConductivity and electron transport properties of VN-CNT interface. Experimental modified CNT array by the vertical VN nanoplatelets synthesis by lyophilization and heat treatment method. Synthesis method is simple, safe, synthesized material having a novel array structure and purity and good crystallinity. Characterization of morphology and structure of the material

2. FIG. (A-c) V2O5 · nH2O and VN / CNTs morphology FIG. Analysis (d-i) VN N-CNT and the morphology, structure and elements.

2. Preparation of the sensing device with superior properties

using a simple knife coating method and a transfer method, firmly bonded to achieve nano-sensitive material of the flexible substrate, thereby preparation of high performance flexible strain sensor. The brush material having a unique class sandwich the stacked structure, the device may be turned off by the slippage between VN / CNTs nanostructures at a slight strain, causing significant changes in the resistance of the device. Preparation sensor (<10%)表现出优异的探测灵敏度(GF = 386),良好的响应速度和耐久度。

FIG. 3. (a) of the flexible sensor working under small strain schematic (bc) of the flexible sensor. (DH) characterization of the flexible sensor.

3, application of the device in the man-machine control system of the flexible sensor

is prepared using the sensing properties of the human articulation, is designed based on the real-time man-machine VN / CNTs of the flexible sensor control system, successfully synchronized manual control of the robot movement.

Figure 4. real-time man-machine control system VN / CNTs flexible strain sensor. (a) signal bent finger. (BD) and a control circuit diagram of a real-time man-machine control system of FIG presentations.

4, the human body wearable monitoring weak signal comfort evaluation

the flexible sensor successfully prepared applied to the human body detecting weak signals, such as voice recognition (different words, different accent identification), a pulse monitor (different sex and physiological state identification) and respiratory rate monitoring (deep breathing, normal breathing, shortness of breath), etc. in addition, the flexible sensor may be wearing comfort were evaluated, such as skin bonding property, heat resistance and the like.

FIG.VN / CNTs flexible strain sensors detect a weak signal on the human body. (A-c) voice recognition. (D-e) monitoring the pulse. (F) respiratory monitoring. Good (g-h) of wearable devices, display comfort and heat dissipation.

Fourth, the summary and outlook:

OF A novel and simple method for in situ synthesis catalysis, synthesis of a three-dimensional conductive network VN / CNTs gas condensate plastic hybrid materials. Wherein the synthesized VN / CNTs having distinct sandwich structure, significantly improves the electrical conductivity, the conductive material may be applied to the strain sensor. Meanwhile, the use of micropatterned templates simple method was developed based on high-sensitivity strain sensor flexibility VN / CNTs of. Based on the above advantages, the slide and separate overlapped CNT array arranged on VN nano-sheet exhibits a high gauge factor 386 at 10% of the small strain, and shows the advantages of fast response and excellent durability (1000 cycles), etc. . Moreover, the sensor detects body movement in the outstanding performance, sound signals and medical aspects, and successfully applied to the prepared sensor robot hand real-time control system, showing great potential commercialization of human-computer interaction.

V. Acknowledgments:

thank the National Natural Science Foundation of China (51872139), Natural Science Foundation of Jiangsu Province (BK20170045), high-level overseas talent introduction plan (plan 1,211,019 thousand), Jiangsu Province six talents peak project (XCL-043), funded Shaanxi Province Natural Science basic Research Program (2019JLM-28) and special funds of the central fundamental Research Universities. References: Hongjian Zhang, Wenqi Han, Kui Xu, Yu Zhang, Yufei Lu, Zhentao Nie, Yuhang Du, Jixin Zhu *, Wei Huang *, Metallic Sandwiched-Aerogel Hybrids Enabling Flexible and Stretchable Intelligent Sensor, Nano Letters, doi:10.1021 / acs.nanolett.0c00372.