Large Stroke Microscale Actuators Based on Electrowetting

该奖项的研究目标是测试集总参数模型和基本标度律可以预测微尺度电润湿致动器所施加的动态力的假设。 为了实现这一目标，必须表征液滴驱动期间施加的力。 在这项工作中使用的方法是分别表征力和电气特性的致动系统在静态条件下。 这些响应将被组合成等效的能量存储和阻尼效应，类似于传统的机械致动器的动态模型。 将使用动态测试对模型进行评估和改进。 微尺度定位和致动方法受限于致动器的相对大的尺寸以及在不损坏它们的情况下抓取和释放小物体的挑战。 当前定位和致动小物体的方法限于小运动和/或需要庞大的宏观尺度部件。该项目将通过调整从微流体中移动单个液滴的方法，使小液滴能够用于移动部件。 如果成功，这项工作将提供新的方法，定位亚毫米部件和驱动微型设备的高速和精度。 然而，电润湿可以仅使用容易制造的衬底和电源容易地致动大距离。 这种能力将促进许多微尺度系统的操纵和驱动。 它可能特别适合于将由不同工艺和/或材料制成的小部件组装成具有比通过原位制造所能实现的更高水平的性能的系统。 潜在的应用包括能量收集装置、小型机器人和其他微机电系统的组装。 来自该提议的知识也将有益于电润湿的其他应用，包括低成本医疗诊断和显示应用。

The research objective of this award is to test the hypothesis that lumped parameter models and basic scaling laws can predict the dynamic forces applied by microscale electrowetting actuators. To realize this goal, the forces applied during droplet actuation must be characterized. The approach used in this work is to separately characterize the force and electrical characteristics of the actuation system under static conditions. These responses will be combined into equivalent energy storage and damping effects that are analogous to dynamic models of conventional mechanical actuators. The models will be evaluated and refined using dynamic testing. Microscale positioning and actuation methods are limited by the relatively large size of the actuators and the challenge of grasping and releasing small objects without damaging them. Current methods of positioning and actuating small objects are limited to small motions and/or require bulky macroscale components. This project will enable the use of small droplets to move parts by adapting methods for moving individual droplets from microfluidics. If successful, this work will provide new methods for positioning sub-millimeter parts and actuating microscale devices with high speed and precision. However, electrowetting can readily actuate large distances using only easily manufactured substrates and an electrical source. This capability will facilitate the manipulation and actuation of many microscale systems. It may be particularly suited for the assembly of small parts made from different processes and/or materials into systems with higher levels of performance than can be achieved through in-situ manufacturing. Potential applications include the assembly of energy harvesting devices, small scale robots, and other microelectromechanical systems. The knowledge from this proposal will also benefit other applications of electrowetting including low cost medical diagnostics and display applications.