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arXiv · 2510.08106

Beyond hospital reach: Autonomous lightweight ultrasound robot for liver sonography

Abstract

Liver disease is a major global health burden. While ultrasound is the first-line diagnostic tool, liver sonography requires locating multiple non-continuous planes from positions where target structures are often not visible, for biometric assessment and lesion detection, requiring significant expertise. However, expert sonographers are severely scarce in resource-limited regions. Here, we develop an autonomous lightweight ultrasound robot comprising an AI agent that integrates multi-modal perception with memory attention for localization of unseen target structures, and a 588-gram 6-degrees-of-freedom cable-driven robot. By mounting on the abdomen, the system enhances robustness against motion. Our robot can autonomously acquire expert-level standard liver ultrasound planes and detect pathology in patients, including two from Xining, a 2261-meter-altitude city with limited medical resources. Our system performs effectively on rapid-motion individuals and in wilderness environments. This work represents the first demonstration of autonomous sonography across multiple challenging scenarios, potentially transforming access to expert-level diagnostics in underserved regions.

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Zihan Li, Yixiao Xu, Lei Zhang, Taiyu Han, Xinshan Yang, Yingni Wang, Mingxuan Liu, Shenghai Xin, Linxun Liu, Hongen Liao, Guochen Ning. 2025-10-09. Beyond hospital reach: Autonomous lightweight ultrasound robot for liver sonography. https://arxiv.org/abs/2510.08106

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