Layered assembly is a voxel-based additive manufacturing process that relies on parallel grasping of voxels to produce multi-material parts. Although there exists substantial diversity in mechanisms of gripping, there still exists a lack of consistency, accuracy, and efficacy in positioning very large numbers of milli-, micro-, and nano-scale objects. We demonstrate the use of parallel electro-osmotic grippers to selectively transport multiple millimeter-sized voxels simultaneously. In contrast to previous research focused on using arrays of droplets to grab a single substrate, each element in the array is individually controlled via capillary effects, which are, in turn, controlled by an electric field to create predetermined patterns of droplets to pick and place selected objects. The demonstrated fluidic pick-and-place method has two key advantages: It is suitable for transport of fragile and complex objects due to the lack of mechanical contact, and it easily parallelizes to arbitrary array sizes for massively parallel pick-and-place. This work demonstrates a 25-element parallel assembly of 1.5-mm spheres with 95–98% grasping reliability, in a variety of geometric patterns. Experimental performance was validated against both analytical and computational models. The results suggest that electro-osmotic droplet arrays may enable the additive manufacturing of multi-material objects containing millions of components in the same print bed.

中文翻译：

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分层组装的电渗透夹具表征

分层装配是一种基于体素的增材制造工艺，依靠体素的并行抓取来生产多材料零件。尽管抓取机制存在很大的多样性，但在定位大量毫米级、微米级和纳米级物体时仍然缺乏一致性、准确性和有效性。我们演示了使用并行电渗夹具来同时选择性地传输多个毫米大小的体素。与之前专注于使用液滴阵列抓取单个基板的研究相比，阵列中的每个元件都是通过毛细管效应单独控制的，而毛细管效应又由电场控制，以创建预定的液滴图案来拾取和放置选定的对象。所展示的流体拾放方法具有两个关键优势：由于缺乏机械接触，它适合运输易碎和复杂的物体，并且它可以轻松并行化到任意阵列尺寸以进行大规模并行拾放。这项工作展示了 1.5 毫米球体的 25 元件并行组装，在各种几何图案中具有 95-98% 的抓取可靠性。实验性能根据分析模型和计算模型进行了验证。结果表明，电渗液滴阵列可以在同一打印床上增材制造包含数百万个组件的多材料物体。