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  1. null (Ed.)
    Unmanned aerial vehicles (UAVs), equipped with a variety of sensors, are being used to provide actionable information to augment first responders’ situational awareness in disaster areas for urban search and rescue (SaR) operations. However, existing aerial robots are unable to sense the occluded spaces in collapsed structures, and voids buried in disaster rubble that may contain victims. In this study, we developed a framework, AiRobSim, to simulate an aerial robot to acquire both aboveground and underground information for post-disaster SaR. The integration of UAV, ground-penetrating radar (GPR), and other sensors, such as global navigation satellite system (GNSS), inertial measurement unit (IMU), and cameras, enables the aerial robot to provide a holistic view of the complex urban disaster areas. The robot-collected data can help locate critical spaces under the rubble to save trapped victims. The simulation framework can serve as a virtual training platform for novice users to control and operate the robot before actual deployment. Data streams provided by the platform, which include maneuver commands, robot states and environmental information, have potential to facilitate the understanding of the decision-making process in urban SaR and the training of future intelligent SaR robots. 
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  2. Abstract

    Many vision‐based indoor localization methods require tedious and comprehensive pre‐mapping of built environments. This research proposes a mapping‐free approach to estimating indoor camera poses based on a 3D style‐transferred building information model (BIM) and photogrammetry technique. To address the cross‐domain gap between virtual 3D models and real‐life photographs, a CycleGAN model was developed to transform BIM renderings into photorealistic images. A photogrammetry‐based algorithm was developed to estimate camera pose using the visual and spatial information extracted from the style‐transferred BIM. The experiments demonstrated the efficacy of CycleGAN in bridging the cross‐domain gap, which significantly improved performance in terms of image retrieval and feature correspondence detection. With the 3D coordinates retrieved from BIM, the proposed method can achieve near real‐time camera pose estimation with an accuracy of 1.38 m and 10.1° in indoor environments.

     
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