ReaDy-Go: Real-to-Sim Dynamic 3D Gaussian Splatting Simulation for Environment-Specific Visual Navigation with Moving Obstacles

Seungyeon Yoo, Youngseok Jang, Dabin Kim, Youngsoo Han, Seungwoo Jung, H. Jin Kim,
Seoul National University

ReaDy-Go achieves robust visual navigation under sim-to-real transfer and moving obstacles by proposing a real-to-sim dynamic environment simulation pipeline for policy training.

Abstract

Visual navigation models often struggle in real-world dynamic environments due to limited robustness to the sim-to-real gap and the difficulty of training policies tailored to target deployment environments (e.g., households, restaurants, and factories). Although real-to-sim navigation simulation using 3D Gaussian Splatting (GS) can mitigate these challenges, prior GS-based works have considered only static scenes or non-photorealistic human obstacles built from simulator assets, despite the importance of safe navigation in dynamic environments. To address these issues, we propose ReaDy-Go, a novel real-to-sim simulation pipeline that synthesizes photorealistic dynamic scenarios in target environments by augmenting a reconstructed static GS scene with dynamic human GS obstacles, and trains navigation policies using the generated datasets. The pipeline provides three key contributions: (1) a dynamic GS simulator that integrates static scene GS with a human animation module, enabling the insertion of animatable human GS avatars and the synthesis of plausible human motions from 2D trajectories, (2) a navigation dataset generation framework that leverages the simulator along with a robot expert planner designed for dynamic GS representations and a human planner, and (3) robust navigation policies to both the sim-to-real gap and moving obstacles. The proposed simulator generates thousands of photorealistic navigation scenarios with animatable human GS avatars from arbitrary viewpoints. ReaDy-Go outperforms baselines across target environments in both simulation and real-world experiments, demonstrating improved navigation performance even after sim-to-real transfer and in the presence of moving obstacles. Moreover, zero-shot sim-to-real deployment in an unseen environment indicates its generalization potential.

Video

ReaDy-Go Overview

The proposed photorealistic simulation pipeline for visual navigation in dynamic environments consists of three main components: (1) a real-to-sim dynamic 3D Gaussian Splatting (GS) simulator with animatable human GS avatars, (2) photorealistic navigation dataset generation for dynamic scenarios, and (3) visual navigation policy training.

ReaDy-Go Overview

ReaDy-Go overview figure.

ReaDy-Go Simulation Visualization

ReaDy-Go generates photorealistic real-to-sim navigation datasets for dynamic scenes. The proposed human animation module synthesizes plausible body motions for human GS avatars within static GS scenes along given 2D trajectories, without relying on a physics engine. ReaDy-Go supports scalable generation of thousands of photorealistic navigation scenarios via expert and human planners.

Real-World Visual Navigation Experiments

Sim-to-Real Transfer

ReaDy-Go demonstrates robust sim-to-real transfer of policies trained solely in simulation (video speed x2). ReaDy-Go achieves higher success rates and lower average reaching times than baseline methods in both static and dynamic environments, although baselines require up to 15x more parameters.


Zero-Shot Sim-to-Real Transfer in an Unseen Environment

ReaDy-Go shows generalization via zero-shot sim-to-real deployment in an unseen environment (video speed x2). The policy achieves over a 50% success rate in both Static and Dynamic tasks. These results suggest that the policy learns general navigation behaviors, such as detouring around static and dynamic obstacles while reaching the goal. ReaDy-Go can provide a scalable approach toward general navigation if trained on larger navigation datasets from diverse environments.

Quantitative Results

Simulation Results

Training environment-specific navigation policies using real-to-sim simulation is crucial for safe and efficient navigation. ReaDy-Go and Vid2Sim, both trained in real-to-sim target environments, achieve higher success rates and lower average reaching times than general navigation models (GNM, NoMaD, and ViNT) across all tasks and environments. This performance is particularly notable given that the general models require up to 15 times more parameters.

Simulation Quantitative Results

Real-World Results

We observe three key takeaways from real-world experiments. First, the photorealistic real-to-sim simulation of ReaDy-Go facilitates sim-to-real transfer of visual navigation policies trained solely in simulation. ReaDy-Go achieves comparable success rates in both Static and Dynamic tasks in the real world, consistent with its simulation results across all environments. Second, environment-specific policies (ReaDy-Go and Vid2Sim) trained on real-to-sim datasets for target environments achieve higher success rates and lower average reaching times than the general navigation model (ViNT), although ViNT requires 15 times more parameters. This validates the practicality of ReaDy-Go for robots operating in specific environments, such as households, restaurants, and factories. Lastly, photorealistic dynamic obstacles in ReaDy-Go are a key factor in maintaining visual navigation performance in dynamic environments. In Dynamic, ReaDy-Go shows the highest success rate and the lowest average reaching time, with only a slight performance degradation compared to Static. In contrast, Vid2Sim exhibits a larger performance drop in Dynamic compared to ReaDy-Go. Since the two methods differ only in the training data, i.e., photorealistic human GS dynamic obstacles for ReaDy-Go versus human assets in a physics engine for Vid2Sim, these results suggest that the proposed photorealistic dynamic GS simulation helps improve navigation performance in dynamic scenarios, which is a practical advantage for robot deployment.

Real-World Quantitative Results

BibTeX

@misc{yoo2026readygorealtosimdynamic3d,
      title={ReaDy-Go: Real-to-Sim Dynamic 3D Gaussian Splatting Simulation for Environment-Specific Visual Navigation with Moving Obstacles}, 
      author={Seungyeon Yoo and Youngseok Jang and Dabin Kim and Youngsoo Han and Seungwoo Jung and H. Jin Kim},
      year={2026},
      eprint={2602.11575},
      archivePrefix={arXiv},
      primaryClass={cs.RO},
      url={https://arxiv.org/abs/2602.11575}, 
      }