Outdoor navigation is widely used in daily life, but faces various issues related to the fidelity of outdoor navigation networks. For instance, agents (pedestrians) are often guided via unrealistic detours around places without clear paths (e.g., squares) or if there are vertical constraints such as overpasses/bridges. This is partly explained by the fact that the main sources of navigation networks in current outdoor navigation are two‐dimensional road/street networks. Utilizing a three‐dimensional space‐based navigation model, compatible with some indoor approaches, is a popular way to address the above‐mentioned issues. A 3D space‐based navigation model is generated by treating 3D spaces as nodes and the shared faces as edges. Inputs of this model are enclosed 3D spaces (volumes). However, outdoor spaces are generally open and unbounded. This article puts forward an approach to enclose outdoor spaces and mimic the indoor environments to derive a network based on connectivity and accessibility of spaces. The approach uses 2.5D maps and consists of three major steps: object footprint determination, footprint classification and space creation. Two use cases demonstrate the proposed approach. Enclosing outdoor spaces opens a new research direction toward providing seamless indoor/outdoor navigation for a range of agents.

中文翻译：

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寻找室外边界以进行3D太空导航

户外导航在日常生活中被广泛使用，但是面临着与户外导航网络的保真度有关的各种问题。例如，代理人（行人）经常在不带清晰路径（例如正方形）的地方或不存在立交桥（例如立交桥/桥梁）的情况下，绕着不切实际的绕行路线被引导。当前的室外导航中导航网络的主要来源是二维道路/街道网络，这部分解释了这一事实。利用与某些室内方法兼容的三维空间导航模型，是解决上述问题的一种流行方法。通过将3D空间视为节点，将共享面视为边缘，可以生成基于3D空间的导航模型。该模型的输入是封闭的3D空间（体积）。但是，室外空间通常是开放且不受限制的。本文提出了一种封闭室外空间并模仿室内环境以基于空间的连通性和可访问性来派生网络的方法。该方法使用2.5D贴图，并包括三个主要步骤：对象足迹确定，足迹分类和空间创建。两个用例演示了建议的方法。封闭的室外空间为为一系列特工提供无缝的室内/室外导航开辟了新的研究方向。