With the increasing demand for mobile robots and autonomous vehicles, several approaches for long-term robot navigation have been proposed. Among these techniques, ground segmentation and traversability estimation play important roles in perception and path planning, respectively. Even though these two techniques appear similar, their objectives are different. Ground segmentation divides data into ground and non-ground elements; thus, it is used as a preprocessing stage to extract objects of interest by rejecting ground points. In contrast, traversability estimation identifies and comprehends areas in which robots can move safely. Nevertheless, some researchers use these terms without clear distinction, leading to misunderstanding the two concepts. Therefore, in this study, we survey related literature and clearly distinguish ground and traversable regions considering four aspects: a) maneuverability of robot platforms, b) position of a robot in the surroundings, c) subset relation of negative obstacles, and d) subset relation of deformable objects.

翻译：随着移动机器人和自动驾驶车辆需求的日益增长，多种面向长期机器人导航的方法已被提出。在这些技术中，地面分割与可穿越性估计分别在地面感知与路径规划中扮演着重要角色。尽管这两种技术看似相似，但目标存在本质差异。地面分割将数据划分为地面与非地面元素，因此常作为预处理阶段，通过剔除地面点提取感兴趣目标；而可穿越性估计则用于识别并理解机器人可安全移动的区域。然而，部分研究者对这两个术语的使用界限模糊，导致人们对这两个概念产生误解。为此，本研究通过综述相关文献，从以下四个方面明确区分地面区域与可穿越区域：（a）机器人平台的可操控性，（b）机器人在环境中的位置，（c）负障碍物的子集关系，以及（d）可变形物体的子集关系。