{"ID":2897275,"CreatedAt":"2026-06-01T04:54:23.091178241Z","UpdatedAt":"2026-06-01T04:54:23.091178241Z","DeletedAt":null,"paper_url":"https://arxiv.org/abs/2507.08851","arxiv_id":"2507.08851","title":"OTAS: Open-vocabulary Token Alignment for Outdoor Segmentation","abstract":"Understanding open-world semantics is critical for robotic planning and control, particularly in unstructured outdoor environments. Existing vision-language mapping approaches typically rely on object-centric segmentation priors, which often fail outdoors due to semantic ambiguities and indistinct class boundaries. We propose OTAS - an Open-vocabulary Token Alignment method for outdoor Segmentation. OTAS addresses the limitations of open-vocabulary segmentation models by extracting semantic structure directly from the output tokens of pre-trained vision models. By clustering semantically similar structures across single and multiple views and grounding them in language, OTAS reconstructs a geometrically consistent feature field that supports open-vocabulary segmentation queries. Our method operates in a zero-shot manner, without scene-specific fine-tuning, and achieves real-time performance of up to ~17 fps. On the Off-Road Freespace Detection dataset, OTAS yields a modest IoU improvement over fine-tuned and open-vocabulary 2D segmentation baselines. In 3D segmentation on TartanAir, it achieves up to a 151% relative IoU improvement compared to existing open-vocabulary mapping methods. Real-world reconstructions further demonstrate OTAS' applicability to robotic deployment. Code and a ROS 2 node are available at https://otas-segmentation.github.io/.","short_abstract":"Understanding open-world semantics is critical for robotic planning and control, particularly in unstructured outdoor environments. Existing vision-language mapping approaches typically rely on object-centric segmentation priors, which often fail outdoors due to semantic ambiguities and indistinct class boundaries. We...","url_abs":"https://arxiv.org/abs/2507.08851","url_pdf":"https://arxiv.org/pdf/2507.08851v2","authors":"[\"Simon Schwaiger\",\"Stefan Thalhammer\",\"Wilfried Wöber\",\"Gerald Steinbauer-Wagner\"]","published":"2025-07-08T22:49:03Z","proceeding":"cs.RO","tasks":"[\"cs.RO\"]","methods":"[]","has_code":false}