Manufacturing of High-Performance Tactile Sensors by High Resolution 3D Printing and Conformal Polymer Coating

与人类皮肤一样，触觉传感器是机器人和个性化医疗设备感知环境并与环境互动的电子皮肤。大多数现有的触觉传感器可以检测到头发一样的柔软物体，或者像勺子一样僵硬的物体，但不能同时检测两者。此外，传感时间从毫秒到秒不等，对于检测快速变化的信号(如振动或快速移动的物体)来说，这太慢了。该奖项支持研究高性能触觉传感器的制造，这种传感器可以在微秒内检测不同大小的物体。该项目推进了关于多尺度结构的高分辨率三维打印及其共形聚合物涂层的功能的知识。高性能触觉传感器有可能取代目前使用的传感器，如触摸屏显示器、安全系统、人机交互和虚拟现实设备。该项目解决了形成复杂结构和制造功能材料的制造挑战。这些成果可以为许多需要新颖几何结构和材料的工程应用提供制造工具，如化学传感器、光电探测器、电池、电容器和化学催化剂。该方法还可用于制造具有多尺度结构的生物植入物，以实现更好的细胞附着。该项目向STEM学生，特别是代表不足的少数族裔介绍可穿戴电子和机器人，并刺激他们在工程领域的职业生涯。该项目实现了一种新的制造能力，可以制造从纳米级到厘米级的多个长度尺度的分层架构结构。这种方法是制造功能器件的范式转变，微米级3D打印制造灵活的多尺度衬底，而氧化化学气相沉积(OCVD)技术被用于在聚合物和纳米材料上涂层，以实现导电和传感等功能。该项目在许多方面提高了基本的制造知识。它建立了一种控制亚像素分辨率的时空曝光的方法，这对所有的光聚合过程都有利。通过分析和设计界面特性和附着力特性，该项目建立了共形涂层策略，从而产生无缝但薄的导电层，以最大限度地发挥多尺度图案的效果。通过具有跨越多个长度尺度的几何特征的分层架构形状，它在微秒内确定了结构变形和恢复的传感性能改进和机制。该项目建立了一个新的基准，以评估接触角和对象大小对复杂活动(如机器人对象操作)的传感性能的影响。建立了一套设计传感器形状和设计3D打印和oCVD涂层参数的指南，并向研究社区提供。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Like human skin, tactile sensors are the e-skin for robotics and personalized medical devices to perceive and interact with the environment. Most existing tactile sensors can detect either hair-like soft objects, or spoon-like stiff ones, but not both. Also, the sensing time ranges from milliseconds to seconds, which is too slow for detecting fast-changing signals, such as vibrational or fast-moving objects. This award supports research that investigates the manufacturing of high-performance tactile sensors that can detect various sizes of objects within microseconds. This project advances the knowledge about high-resolution three-dimensional printing of multi-scale structures and their conformal polymer coating for functionality. The high-performance tactile sensors have the potential to replace those currently employed, such as in touch screen displays, security systems, human-machine interaction, and virtual reality devices. The project addresses manufacturing challenges of forming complex structures and making functional materials. The outcomes can provide a manufacturing tool for many engineering applications requiring novel geometries and materials, such as chemical sensors, photodetectors, batteries, capacitors, and chemical catalysts. The method can also be used to make biological implants with multiscale structures for better cell attachment. This project introduces STEM students, especially, underrepresented minorities to wearable electronics and robotics and stimulates them for careers in engineering. This project enables a new manufacturing capability for hierarchically architected structures with multiple length scales from nanoscale to centimeter scale. This approach is a paradigm shift in manufacturing functional devices, where micron-scale 3D printing fabricates the flexible multiscale substrates while the oxidative chemical-vapor-deposition (oCVD) technique is used to coat with polymers and nanomaterials for functionalities, such as conductivity and sensing. The project advances the fundamental manufacturing knowledge in many ways. It establishes a method to control spatial-temporal exposures for sub-pixel resolutions, which benefits all photo-polymerization processes. By analyzing and engineering the interfacial properties and adhesion characteristics, the project establishes conformal coating strategies which result in a seamless but thin conductive layer to maximize the effect of the multiscale patterns. By a hierarchically architected shape with geometry features across multiple length scales, it determines sensing performance improvements and mechanisms for structure deformation and recovery in microseconds. The project establishes a new benchmark to evaluate the effect of contact angle and object size on the sensing performance for sophisticated activities such as robot object manipulation. A set of guidelines to design sensor shapes and engineer 3D printing and oCVD coating parameters is established and is made available to the research community.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.