PAR3D: A Unified 3D-MLLM with Part-Aware Representation for Scene Understanding
On the map: Multimodal LLMs / vision-language models → Embodied and 3D vision-language models
Abstract (arXiv)
Recent advances in 3D multimodal large language models (3D-MLLMs) have enabled unified solutions for 3D scene understanding tasks, including visual question answering, captioning, and referring segmentation. However, existing 3D-MLLMs remain largely object-centric, limiting their ability to model fine-grained part structures that are essential for embodied interaction with 3D environments. In this work, we present PAR3D, a unified part-aware 3D-MLLM framework that enables models to understand, reason about, and ground both objects and their parts in 3D scenes. To enable training and evaluation of part-aware 3D scene understanding, we introduce ScenePart, a synthetic 3D scene dataset with part-level annotations and language instructions. We further develop Part-Aware 3D Representation Learning to enrich 3D visual representations with fine-grained part-level semantics, and propose Hierarchical Segmentation Query Generation to ground part targets via hierarchical object-part queries. Extensive experiments show that our method substantially improves part-level question answering and referring segmentation, while also achieving strong performance across object-level vision-language tasks.
Key facts. Cited by 1 paper in the map (data through 14 Oct 2026). Placed in Embodied and 3D vision-language models, one of 16 directions in Multimodal LLMs / vision-language models. Builds on 62 of its 73 references that are in the map. First posted on arXiv 4 Jun 2026.
Builds on
62 of 73 references.
Closest ancestors · 11
Same direction, newest first
- 2025Part-X-MLLM: Part-aware 3D Multimodal Large Language Model17 Nov
- 2025LEO-VL: Efficient Scene Representation for Scalable 3D Vision-Language Learning11 Jun
- 20253D-LLaVA: Towards Generalist 3D LMMs with Omni Superpoint Transformer2 Jan
- 2024Video-3D LLM: Learning Position-Aware Video Representation for 3D Scene Understanding30 Nov
- 2024LLaVA-3D: A Simple yet Effective Pathway to Empowering LMMs with 3D-awareness26 Sep
- 2024Reason3D: Searching and Reasoning 3D Segmentation via Large Language Model27 May
- 2024When LLMs step into the 3D World: A Survey and Meta-Analysis of 3D Tasks via Multi-modal Large Language Models16 May
- 2024MiniGPT-3D: Efficiently Aligning 3D Point Clouds with Large Language Models using 2D Priors2 May
- 2023PartDistill: 3D Shape Part Segmentation by Vision-Language Model Distillation7 Dec
- 2023GPT4Point: A Unified Framework for Point-Language Understanding and Generation5 Dec
- 2023LL3DA: Visual Interactive Instruction Tuning for Omni-3D Understanding, Reasoning, and Planning30 Nov
Other references · 51
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38 more
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- 2019ScanRefer: 3D Object Localization in RGB-D Scans using Natural Languagecited by 452
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- 2024Grounded 3D-LLM with Referent Tokenscited by 115
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- 2025HMR3D: Hierarchical Multimodal Representation for 3D Scene Understanding with Large Vision-Language Model
- 2025MLLM-For3D: Adapting Multimodal Large Language Model for 3D Reasoning Segmentation
- 2026SceneBench: A Hierarchical Benchmark for Vision-Language Understanding of 3D Scenes
- 20253UR-LLM: An End-to-End Multimodal Large Language Model for 3D Scene Understanding
- 20263D-PLOT-LLM: Part-Level Object Tokens for 3D Large Language Models
- 2024PARIS3D: Reasoning-based 3D Part Segmentation Using Large Multimodal Model