Selected Publications

# Equal contribution; * Corresponding author.

SurgCast: Action-Conditioned Future Skeletons for Controllable Surgical World Models overview

SurgCast: Action-Conditioned Future Skeletons for Controllable Surgical World Models

Wanhao Liu#, Rulin Zhou#, Liangjing Shao#, Zhaocheng Lin, Dongyue Li, Jinsong Lin, Zhiqing Tang, Jingchen, Panshuo Li, Hongliang Ren*

arXiv preprint · 2026

Abstract

SurgCast predicts future instrument skeletons from the current skeleton, robot state, and prospective actions, then uses these structures to control surgical video generation. Dual-Path Semantic-Kinematic Injection combines geometric residuals with global-local kinematic modulation, while distribution-matching distillation transfers this interface to a four-step causal student. Experiments on SutureBot and SRTH-Porcine-Cholei evaluate visual quality and instrument control, with additional zero-shot transfer and physical master-device demonstrations.

CrossScope: A Role-Asymmetric World Model for Joint Dual-Scope Surgical Video Prediction overview

CrossScope: A Role-Asymmetric World Model for Joint Dual-Scope Surgical Video Prediction

Wanhao Liu#, Jinsong Lin#, Rulin Zhou#, Chi Kit Ng#, Wenbin Pan, Zhiqing Tang, Dongyue Li, Liwei Luo, Yanshen Wu, Panshuo Li, Zhiyong Xiong, Huxin Gao, Tamas Haidegger, Hongliang Ren*

arXiv preprint · 2026

Abstract

CrossScope studies role-asymmetric future prediction for Mother-Child endoscopic retrograde cholangiopancreatography, where two independently moving scopes provide complementary views without calibrated stereo geometry. Its dual-stream world model preserves view-specific experts and routes cross-view evidence according to target-specific spatial requirements, improving visual fidelity, structural preservation, target localization, and motion consistency.

RoPE-Flow: Monocular Vision-based Robot Pose Estimation via 2D Graph-Conditioned 3D Flow Matching overview

RoPE-Flow: Monocular Vision-based Robot Pose Estimation via 2D Graph-Conditioned 3D Flow Matching

Liangjing Shao, Wanhao Liu, Zhiwei Fang, Rulin Zhou, Quanlu Zhang, Changjing Liu, Beilei Cui, Yiming Huang, Hongliang Ren*

arXiv preprint · 2026

Abstract

RoPE-Flow estimates robot 3D keypoints and joint angles from monocular images using graph-conditioned flow matching. A keypoint feature extractor combines positional cues with multi-scale appearance features, and graph-guided condition generation models correlations among keypoints. Bone-length and ray-depth losses promote topological consistency and scale stability. Evaluation covers different robot types and cameras, including a cross-scene benchmark for zero-shot robot pose estimation.

Surg-UniWorld: A Unified Surgical World Model with Multimodal Control Experts overview

Surg-UniWorld: A Unified Surgical World Model with Multimodal Control Experts

Rulin Zhou#, Wanhao Liu#, Guoheng Ma, Liangjin Shao, Qiujie Song, Yidu Wang, Guankun Wang, Tong Chen, Long Bai, Luping Zhou, Hongliang Ren*

arXiv preprint · 2026

Abstract

Controllable surgical world models can provide a generative foundation for surgical artificial intelligence and simulation by synthesizing realistic instrument-tissue interactions. Surg-UniWorld introduces a Hierarchical Surgical Anchor, Anchor-Relative Modality Experts, and a Multimodal Control Expert to support coherent video generation under arbitrary combinations of edge, depth, and optical-flow controls. Experiments demonstrate improved generation quality, temporal consistency, and multimodal controllability.

EndoWAM: A Grounded World-Action Model for Generalizable Endoscopic Navigation overview

EndoWAM: A Grounded World-Action Model for Generalizable Endoscopic Navigation

Jinsong Lin#, Zikang Pan#, Wanhao Liu#, Chi Kit Ng#, Liangjing Shao, Zihang Yu, Ziyu Wang, Yin Wang, Jiaxi Wang, Jeremy Yuen-Chun Teoh, Zhiyong Xiong, Huxin Gao, Hongliang Ren*

arXiv preprint · 2026

Abstract

EndoWAM is a grounded World-Action Model for generalizable robotic endoscopic navigation. It predicts task-relevant target regions in future observations and couples a lightweight diffusion transformer with a discrete action expert through a shared predictive representation. The model enables real-time control and generalizes to unseen viewpoints, environments, and targets across multiple endoscopic procedures.