Second Skin: Bio-Inspired Tactile Sensing Enabled by Droplet-Based Interfacial Iontronics

目的：人类的环境感受通过接触或相互作用提供了有关环境的广泛信息。受生理触觉功能的启发，该提案旨在在柔性和透明基板上开发高灵敏度的触觉阵列，利用液滴电解质-电极界面处的新型电容传感原理。将建立几种非传统的微制造技术来设计这种独特的触觉传感器，包括微流体矩阵印刷，润湿性微图案化和界面纳米粘附。开发完成后，这种微滴传感器阵列将为一系列医疗和机器人应用提供高度变革性的人工触觉传感平台，具有高设备灵敏度、高空间分辨率和高适应性。新颖的生物启发触觉传感矩阵提供了优于现有传感设计的几个优点，包括电子设备灵敏度（最高灵敏度为0.12nF/kPa），空间分辨率极高（小至0.5mm），双重压力-温度映射能力，快速响应时间（快至1毫秒）、超薄外形和包装（薄至100 μ m），以及由所有柔软材料制成的皮肤状结构，例如，聚合物和液体。重要的是，界面电容传感器对寄生电容高度免疫，其中基极电容比常规对应物的基极电容大100倍以上。此外，简单的器件结构允许低成本但高可靠性的大规模生产。总的来说，拟议的生物启发的离子传感器，一旦建立，可以提供一个高度变革性的解决方案，神经处理，机器人，医疗假肢，计算机/视频游戏和外科手术仪器，在这些领域都需要高灵活性和灵敏的反应。更广泛的影响：从拟议的研究令人兴奋的发现将完全结合教育工作。PI一直积极推动各级尖端微纳米技术的教育。他通过在线开放渠道，将消费电子产品转化为桌面微加工工具，积极参与向公众传播洁净室外微加工概念。通过K-12教育外展，PI将领导一项将触觉传感引入K-12教室的外展计划，将人工触觉传感的研究发现转化为本地高中生的即插即用演示套件。此外，通过NSF赞助的暑期实习计划，将直接为代表性不足的本科生和高中生提供生物感应概念的教育机会。

Objective: Human tactioception provides extensive information about the environment upon contact or through interactions. Inspired by the physiological tactile functions, this proposal aims to develop a highly sensitive tactile array on flexible and transparent substrates, utilizing a novel capacitive sensing principle at a droplet electrolyte-electrode interface. Several unconventional microfabrication techniques will be established to devise this unique tactile sensors with all flexible components, including microfluidic matrix printing, wettability micropatterning, and interfacial nano-adhesion. Upon development, such an array of the microdroplet sensors would enable a highly transformative platform of artificial tactile sensing for a range of medical and robotic applications with high device sensitivity, high spatial resolution and high adaptability.Intellectual Merit: The novel bio-inspired tactile sensing matrix offers several advantages over existing sensing designs, including ultrahigh device sensitivity (the highest sensitivity of 0.12nF/kPa at its dimension), ultrafine spatial resolution (down to 0.5mm), dual pressure-temperature mapping capacity, fast response time (as quick as 1 milliseconds), ultralow profile with packaging (as thin as 100ìm), in addition to its skin-like construct made from all soft materials, e.g., polymers and liquids. Importantly, the interfacial capacitive sensor is highly immune to parasitic capacitance, in which the base capacitance is more than 100 times greater than that of the conventional counterpart. Moreover, the simple device architecture permits mass-production at low cost yet high reliability. Overall, the proposed bio-inspired iontronic sensors, once established, could offer a highly transformative solution to various fundamental and translational fields of neural processing, robotics, medical prosthetics, computer/video gaming, and surgical instruments, where both high flexibility and sensitive responses are demanded.Broader Impacts: Exciting discoveries from the proposed research will be fully integrated with the educational efforts. The PI has been actively promoting education of cutting-edge micro-nanotechnology at all levels. He is actively engaged in disseminating the out-of-cleanroom microfabrication concept by converting consumer electronics into desktop microfabrication tools to the general public through online open-access channels. Through the K-12 educational outreach, the PI will lead an outreach initiative of Introducing Tactile Sensing into K-12 Classroom by turning the research discoveries on the artificial tactile sensing to a plug-and-play demonstration kit for local high-school students. Moreover, education opportunities will be directly provided to underrepresented undergraduate and high-school students on bio-inspired sensing concepts through a NSF-sponsored summer internship program.