This letter presents MAMMOBOT, one of the first millimetre-scale steerable soft growing robots for medical applications. MAMMOBOT aims to access the breast through the nipple and navigate the mammary ducts to detect precursors of invasive breast cancers. Addressing limitations of the state-of-the-art, MAMMOBOT maintains a hollow inner lumen throughout its soft body, enabling the passing of instruments such as miniature endoscopes, biopsy needles, and optical probes for in situ histopathology. MAMMOBOT is developed by a novel manufacturing approach entailing dual LDPE sheet adhesion with localised heat treatment. MAMMOBOT's steerability is achieved through a sub-millimetre profiled tendon-driven catheter that passes through its inner lumen. A duty cycle controller governs steering versus growing to achieve navigation in complex environments within a human-in-the-loop framework. Benchtop experimental evaluation demonstrates the robot's capabilities and agreement with a Reduced-Order Mode (ROM) of its dynamics. Finally, experimental evaluation on a bespoke breast phantom developed for the purposes of this project demonstrates the clinical relevance and potential impact of MAMMOBOT.

中文翻译：

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MAMMOBOT：用于早期乳腺癌检测的微型可操纵软生长机器人


这封信介绍了 MAMMOBOT，这是首款用于医疗应用的毫米级可操纵软体生长机器人之一。 MAMMOBOT 旨在通过乳头进入乳房并导航乳腺导管以检测浸润性乳腺癌的前兆。为了解决最先进技术的局限性，MAMMOBOT 在其柔软的身体中保持了一个中空的内腔，使得微型内窥镜、活检针和用于原位组织病理学的光学探针等仪器能够通过。 MAMMOBOT 采用新颖的制造方法开发，需要通过局部热处理粘合双 LDPE 片材。 MAMMOBOT 的可操纵性是通过穿过其内腔的亚毫米异形肌腱驱动导管实现的。占空比控制器控制转向与增长，以在人机交互框架内的复杂环境中实现导航。台式实验评估展示了机器人的能力以及与其动力学降阶模式（ROM）的一致性。最后，为本项目开发的定制乳房模型的实验评估证明了 MAMMOBOT 的临床相关性和潜在影响。