Path-level Hindsight Instructions for Semantic Exploration in Vision-Language Navigation
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Abstract (arXiv)
On-policy exploration is a crucial component for training robust Vision-Language Navigation agents, as it exposes the policy to a broader state distribution. However, such exploration inevitably leads to trajectories that deviate from expert demonstrations, resulting in a semantic mismatch between the executed visual stream and the original language instruction. In this work, we address this challenge by introducing Phi-Nav, a unified on-policy framework that leverages hindsight reasoning to align instructions with the agent's actual exploratory journey. Specifically, Phi-Nav operates through a three-stage dual-supervision cycle: 1) the agent performs oracle-guided on-policy exploration, sampling a trajectory while learning from expert action feedback, 2) a hindsight speaker synthesizes a path-level hindsight instruction grounded in the collected visual observations, and 3) the agent conducts a second imitation pass, treating the synthesized trajectory-instruction pair as an additional expert demonstration. Through this process, Phi-Nav bridges the critical semantic supervision gap inherent in on-policy methods, transforming semantically unlabeled movement into dense training signals. Evaluations on the R2R-CE and RxR-CE benchmarks show that Phi-Nav yields competitive performance while requiring only a fraction of the expert demonstrations used by current baselines. These results underscore the necessity of semantic exploration in VLN, positioning Phi-Nav as an effective solution for training embodied agents with limited data.
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References · 54
- 2021Learning Transferable Visual Models From Natural Language Supervisioncited by 33,456
- 2020Language Models are Few-Shot Learnerscited by 32,199
- 2022ReAct: Synergizing Reasoning and Acting in Language Modelscited by 8,355
- 2024GPT-4o System Cardcited by 4,467
- 2023Reflexion: Language Agents with Verbal Reinforcement Learningcited by 4,064
- 2025Qwen3-VL Technical Reportcited by 2,534
- 2021CLIPScore: A Reference-free Evaluation Metric for Image Captioningcited by 2,388
- 2019Dream to Control: Learning Behaviors by Latent Imaginationcited by 1,598
- 2019Habitat: A Platform for Embodied AI Researchcited by 1,163
- 2017Hindsight Experience Replaycited by 1,096
- 2022Language Models as Zero-Shot Planners: Extracting Actionable Knowledge for Embodied Agentscited by 1,029
- 2017Vision-and-Language Navigation: Interpreting visually-grounded navigation instructions in real environmentscited by 1,013
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- 2015Scheduled Sampling for Sequence Prediction with Recurrent Neural Networkscited by 779
- 2019Model-Based Reinforcement Learning for Ataricited by 495
- 2018Data-Efficient Hierarchical Reinforcement Learningcited by 436
- 2020Beyond the Nav-Graph: Vision-and-Language Navigation in Continuous Environmentscited by 429
- 2020Object Goal Navigation using Goal-Oriented Semantic Explorationcited by 421
- 2018Speaker-Follower Models for Vision-and-Language Navigationcited by 337
- 2018Reinforced Cross-Modal Matching and Self-Supervised Imitation Learning for Vision-Language Navigationcited by 304
- 2021History Aware Multimodal Transformer for Vision-and-Language Navigationcited by 268
- 2018Visual Reinforcement Learning with Imagined Goalscited by 248
- 2019Learning to Navigate Unseen Environments: Back Translation with Environmental Dropoutcited by 241
- 2024NaVILA: Legged Robot Vision-Language-Action Model for Navigationcited by 201
- 2022Think Global, Act Local: Dual-scale Graph Transformer for Vision-and-Language Navigationcited by 187
- 2023ETPNav: Evolving Topological Planning for Vision-Language Navigation in Continuous Environmentscited by 165
- 2022Bridging the Gap Between Learning in Discrete and Continuous Environments for Vision-and-Language Navigationcited by 127
- 2022BEVBert: Multimodal Map Pre-training for Language-guided Navigationcited by 117
- 2025StreamVLN: Streaming Vision-and-Language Navigation via SlowFast Context Modelingcited by 107
- 2018Temporal Difference Models: Model-Free Deep RL for Model-Based Controlcited by 89
- 2025JanusVLN: Decoupling Semantics and Spatiality with Dual Implicit Memory for Vision-Language Navigationcited by 80
- 2023Positive-Augmented Contrastive Learning for Image and Video Captioning Evaluationcited by 78
- 2020ViNG: Learning Open-World Navigation with Visual Goalscited by 77
- 2024Towards Long-Horizon Vision-Language Navigation: Platform, Benchmark and Methodcited by 66
- 2024Lookahead Exploration with Neural Radiance Representation for Continuous Vision-Language Navigationcited by 63
- 2021Less is More: Generating Grounded Navigation Instructions from Landmarkscited by 62
- 2025VLN-R1: Vision-Language Navigation via Reinforcement Fine-Tuningcited by 61
- 2022A New Path: Scaling Vision-and-Language Navigation with Synthetic Instructions and Imitation Learningcited by 60
- 2024Constraint-Aware Zero-Shot Vision-Language Navigation in Continuous Environmentscited by 49
- 2021EMScore: Evaluating Video Captioning via Coarse-Grained and Fine-Grained Embedding Matchingcited by 36
- 2021Vision-Language Navigation: A Survey and Taxonomycited by 33
- 2024Learning Robust Autonomous Navigation and Locomotion for Wheeled-Legged Robotscited by 32
- 2025Generate, but Verify: Reducing Hallucination in Vision-Language Models with Retrospective Resamplingcited by 32
- 2018Hierarchical Reinforcement Learning with Hindsightcited by 26
- 2018Energy-Based Hindsight Experience Prioritizationcited by 20
- 2024Controllable Navigation Instruction Generation with Chain of Thought Promptingcited by 20
- 2024Navigation Instruction Generation with BEV Perception and Large Language Modelscited by 20
- 2024Vision-Language Navigation with Energy-Based Policycited by 19
- 2024g3D-LF: Generalizable 3D-Language Feature Fields for Embodied Taskscited by 18
- 2019HIGhER : Improving instruction following with Hindsight Generation for Experience Replaycited by 13
- 2025ActiveVLN: Towards Active Exploration via Multi-Turn RL in Vision-and-Language Navigationcited by 11
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