发表机构
Space Engineering University（航天工程大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
PhysX-CoT将单张图像生成仿真3D资产视为显式结构化物理推理过程，通过分解部件级状态轨迹优化相关指标，在多方面优于基线，生成资产在Unreal Engine 5中表现良好。
AI 中文摘要
可用于仿真的3D资产是机器人技术和具身人工智能的核心，从单张图像生成这类资产通常被视为一种视觉-语言模型，该模型输出序列化资产供解码器转换为几何结构和物理场，却将图像到3D的推理过程隐含处理。我们认为这种以输出为中心的视角是限制因素：部件放置和局部形状在全局坐标标记流中相互纠缠，且中间物理状态从未被暴露以用于监督、条件设置或验证。PhysX-CoT则将单张图像资产生成视为显式结构化物理推理过程，这是一个有序且机器可解析的部件级状态轨迹，涵盖分解、2D与3D grounding（对齐）、关系、粗几何和表面线索，我们对这些轨迹分别进行监督、用于条件设置几何结构，并将其作为奖励目标。几何结构被分解，使得3D框承载放置信息，局部编码承载形状信息，且与思维链（CoT）对齐的GRPO优化了解析有效性、grounding、几何结构、放置和物理一致性。在统一协议下，所有学习到的基线模型在相同的骨干网络、数据和冻结解码器上进行重新训练，PhysX-CoT在几何结构、尺度和物理属性指标上优于最接近的全任务基线。Oracle、标记匹配和状态顺序控制实验表明，这些显式状态具有功能性而非装饰性，在Unreal Engine 5中，生成的资产具有高解析、碰撞和关节运动有效性。
英文摘要
Simulation-ready 3D assets are central to robotics and embodied AI. Generating them from a single image is usually framed as a vision-language model that emits a serialized asset for a decoder to turn into geometry and physical fields, leaving the image-to-3D reasoning implicit. We argue the limiting factor is this output-centric view: part placement and local shape are entangled in one global-coordinate token stream, and the intermediate physical states are never exposed for supervision, conditioning, or verification. PhysX-CoT instead casts single-image asset generation as an explicit structured physical reasoning process, an ordered and machine-parseable trajectory of part-level states covering decomposition, 2D and 3D grounding, relations, coarse geometry, and surface cues that we separately supervise, use to condition geometry, and treat as reward targets. Geometry is factorized so that 3D boxes carry placement and local codes carry shape, and CoT-aligned GRPO optimizes parse validity, grounding, geometry, placement, and physical consistency. Under a unified protocol that retrains all learned baselines on the same backbone, data, and frozen decoder, PhysX-CoT outperforms the closest full-task baseline across geometry, scale, and physical-attribute metrics. Oracle, token-matched, and state-order controls show the explicit states are functional rather than cosmetic, and in Unreal Engine~5 the generated assets parse, collide, and articulate at high validity.
