Floating magnetic microrobots for fiber functionalization
Floating magnetic microrobots for fiber functionalization
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DOI：
10.1126/scirobotics.aax8336
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发表时间：
2019-09-25
期刊：
影响因子：
25
通讯作者：
Yang，Guang-Zhong
中科院分区：
文献类型：
--
作者：
Barbot，Antoine;Tan，Haijie;Yang，Guang-Zhong
由于微创手术越来越多地用于靶向小病变，因此对微型化工具的需求也在增长，例如微导管、铰接式微镊子或镊子，这些工具结合了传感和致动，用于精密手术。虽然现有的微制造技术已经解决了这些设备的建设，准确的集成和功能化的化学和物理传感器代表主要的挑战。本文提出了一种用于直径为140至830微米的纤维功能化的微机器人平台，图案化精度为5微米，定向误差小于0.4°。为了实现这一目标，我们开发了两个2毫米× 3毫米、200微米厚的微型机器人，用于在湿法转移过程中对准光纤上的浮动电子电路。微型机器人的位置和方向在空气/水界面处由永磁体控制。受控位置的刚度为0.2牛顿毫米，导致0.5牛顿的平均力。磁体的非均匀磁场与记录在微型机器人中的不同优选磁化方向相关联，允许精确控制两个微型机器人之间的距离。这个额外的自由度用于控制微型机器人对作为镊子来抓取和释放浮动的电子图案，而其他自由度用于将图案位置和方向与纤维对齐。提出了这种控制的模型，以及微型机器人通过表面张力的相互作用。提供了详细的性能验证，并演示了200微米直径的光纤和三维设备上的各种示例性传感器实施例。
Because minimally invasive surgery is increasingly used to target small lesions, demand is growing for miniaturized tools—such as microcatheters, articulated microforceps, or tweezers—that incorporate sensing and actuation for precision surgery. Although existing microfabrication techniques have addressed the construction of these devices, accurate integration and functionalization of chemical and physical sensors represent major challenges. This paper presents a microrobotic platform for the functionalization of fibers of diameters from 140 to 830 micrometers, with a patterning precision of 5 micrometers and an orientation error below 0.4°. To achieve this, we developed two 2 millimeter–by–3 millimeter, 200-micrometer-thick microrobots to align floating electronic circuits on a fiber during a wet transfer process. The position and orientation of the microrobots were controlled at the air/water interface by a permanent magnet. The stiffness of the position controlled was 0.2 newton millimeter, leading to an average force of 0.5 newton. The nonhomogeneous magnetic field of the magnet, associated with different preferred magnetization directions recorded in the microrobots, allowed the distance between the two microrobots to be precisely controlled. This extra degree of freedom was used to control the microrobot pair as a tweezer to grab and release floating electronic patterns, whereas the others were used to align the pattern position and orientation with the fiber. A model of this control, as well as the microrobots’ interaction through surface tension, is proposed. Detailed performance validation is provided, and various exemplar sensor embodiments on a 200-micrometer-diameter fiber and three-dimensional devices are demonstrated.