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arXiv · 2311.13809

Responsive Hydrogel-based Modular Microrobots for Multi-functional Micromanipulation

Liyuan Tan·David J. Cappelleri
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Abstract

Microrobots show great potential in biomedical applications such as drug delivery and cell manipulations. However, current microrobots are mostly fabricated as a single entity and type and the tasks they can perform are limited. In this paper, modular microrobots, with an overall size of 120 $μ$m $\times$ 200 $μ$m, are proposed with responsive mating components, made from stimuli-responsive hydrogels, and application specific end-effectors for microassembly tasks. The modular microrobots are fabricated based on photolithography and two-photon polymerization together or separately. Two types of modular microrobots are created based on the location of the responsive mating component. The first type of modular microrobot has a mating component that can shrink upon stimulation while the second type has a double bilayer structure that can realize an open and close motion. The exchange of end-effectors with an identical actuation base is demonstrated for both types of microrobots. Finally, different manipulation tasks are performed with different types of end-effectors.

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Liyuan Tan, David J. Cappelleri. 2023-11-23. Responsive Hydrogel-based Modular Microrobots for Multi-functional Micromanipulation. https://arxiv.org/abs/2311.13809

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