This paper introduces an autonomous system employing multirotor unmanned aerial vehicles for fast 3D exploration and inspection of vast, unknown, dynamic, and complex environments containing large open spaces as well as narrow passages. The system exploits the advantage of small-size aerial vehicles capable of carrying all necessary sensors and computational power while providing full autonomy and mobility in constrained unknown environments. Particular emphasis is put on the robustness of the algorithms with respect to challenging real-world conditions and the real-time performance of all algorithms that enable fast reactions to changes in environment and thus also provide effective use of limited flight time. The system presented here was employed as a part of a heterogeneous ground and aerial system in the modeled Search & Rescue scenario in an unfinished nuclear power plant during the Urban Circuit of the Subterranean Challenge (SubT Challenge) organized by the Defense Advanced Research Projects Agency. The main goal of this simulated disastrous scenario is to autonomously explore and precisely localize specified objects in a completely unknown environment and to report their position before the end of the mission. The proposed system was part of the multirobot team that finished in third place overall and in first place among the self-funded teams. The proposed unmanned aerial vehicle system outperformed all aerial systems participating in the SubT Challenge with respect to versatility, and it was also the self-deployable autonomous aerial system that explored the largest part of the environment.

中文翻译：

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一种用于快速探索大型复杂室内环境的自主无人机系统

本文介绍了一种采用多旋翼无人机的自主系统，用于对包含大型开放空间和狭窄通道的广阔、未知、动态和复杂环境进行快速 3D 探索和检查。该系统利用了小型飞行器的优势，该飞行器能够携带所有必要的传感器和计算能力，同时在受限的未知环境中提供完全的自主性和机动性。特别强调算法在具有挑战性的现实世界条件方面的鲁棒性以及所有算法的实时性能，这些算法能够对环境变化做出快速反应，从而有效利用有限的飞行时间。这里介绍的系统被用作建模搜索和空中系统中异构地面和空中系统的一部分。由国防高级研究计划局组织的地下挑战城市巡回赛（SubT 挑战）期间未完工核电站的救援场景。这种模拟灾难性场景的主要目标是在完全未知的环境中自主探索和精确定位指定物体，并在任务结束前报告它们的位置。提议的系统是多机器人团队的一部分，该团队在总体上获得第三名，并在自筹资金团队中名列第一。拟议的无人机系统在多功能性方面优于所有参与 SubT 挑战的航空系统，它也是探索最大部分环境的可自行部署的自主航空系统。