基于触觉传感与触觉映射的人机交互系统

近年来，柔性电子、人工智能、机器人技术迅速兴起促进了人机交互的发展。作为人机交互的两大重要领域，触觉传感和触觉反馈往往被孤立开来，鲜有研究将这两种技术有机融合为一体。本文开展了触觉传感与触觉映射的研究，并基于两者构建了人机交互系统，初步解决了上述问题。

本文研制了一种离子-电子型柔性压力传感器，该传感器采用聚乙烯醇和磷酸凝胶材料作为离子导电层，通过软光刻技术制备了非稳自填充结构，极大地提高了传感性能。其灵敏度极高，可以超过400 kPa^-1；同时还具有响应时间短、循环稳定性好等性能。

本文还制备了振动反馈可穿戴设备。选用小型商用马达作为振动反馈可穿戴设备的驱动器，并嵌入到硅胶与涤纶织物中，制备了振动反馈可穿戴设备。

进一步地，实现了触觉传感器和振动反馈可穿戴设备的集成。通过在机械手表面贴附传感阵列，在受试者身上贴附振动反馈可穿戴设备，使用相应的信号传递电路，实现触觉传感器电容值与触觉反馈设备的振动频率一一对应，从而搭建了具备触觉传感与振动反馈映射功能的人机交互系统。本文展示了该系统的两个应用场景，受试者能根据振动反馈信号学习并识别出触觉信息。

本文创新性地结合了超高灵敏柔性压力传感器与振动反馈可穿戴设备，搭建了点对点、实时的、具备较高精度的人机交互系统，为人机交互系统的设计提供了一种切实可行的方案。该系统能够实现从机器触觉到人体触觉的映射，可帮助人体通过振动反馈感知机械手的触觉信息。

In recent years, the emerging of flexible electronics, artificial intelligence and robotics promotes the development of human-computer interaction. However, existing work focuses on either tactile sensing or tactile feedback, without connecting the two functions together. Here, the author and collaborators design a human-computer interaction system based on tactile sensing and tactile feedback, well addressing the aforementioned problem.

The flexible pressure sensor consists of two electrodes and an ionic layer. The ionic layer is a polyvinyl alcohol-phosphoric acid gel, of which the surface is duplicated from a unique sandpaper serving as the template. The device exhibits high sensitivity of >400 kPa^-1, and also presents other excellent properties such as short response time and high cyclic stability.

The author further developed a vibration feedback device. A commercial motor is selected as the vibration feedback device in this study. A sensor array and a set of vibration feedback device are integrated with a circuit to build human-computer interaction system. We have demonstrated two possible applications. The subject volunteer involved in this study was able to judge tactile information according to the vibration feedback signals.

In summary, a real-time, point-by-point, and high-precision human-computer interaction system is demonstrated by combining an array of highly sensitivity flexible pressure sensors and a set of vibration feedback device. The system can respond to the signals captured by the flexible pressure sensor in real time, process the signal, and transfer the information as different vibration frequencies that can be recognized by the human skin. Such a system is expected to be used in artificial limbs to help the user recover tactile sensation.

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