LUNL Gamma Radiation Dataset and SLAM Map

Three files consisting of a txt file dataset of gamma radiation count observations, with SLAM estimated position, and a 2D SLAM map of the Lancaster University Neutron Laboratory (LUNL).The LUNL_radiation_data.txt consists of comma separated values, with a header row indicating the data types. Timestamp is with respect to Unix Epoch time (as is standard in ROS). Spatial coordinates of the robot x, y, z are in metres. As the robot is a ground level 2D robot, the SLAM estimate restricts the Z height to be roughly constant. Only x and y data are necessary. The counts data are in counts per second, indicating the number of events collected over a ~1 second time window by a CeBr3 scintillator detector and mixed field analyser.The map file (.pgm) is a trinary (three value) map generated by SLAM via ROS (Robot Operating System). The three values related to occupied (obstacles and physical features, such as walls), unoccupied (free-space), and unknown.The map metadata file (.yaml) provides values to convert pixel position of the map file into coordinates (in metres).Data was originally collected 05/12/2019 (in ROS bag format), which was interrogated to provide the data in the .txt file.This dataset is then post-processed to provide interpolated maps of gamma radiation, based on the point observations and maps in these files.

本数据集包含三个文件，分别为伽马辐射计数观测的TXT格式数据集（附带同步定位与地图构建（Simultaneous Localization and Mapping，SLAM）估计的机器人位姿），以及兰卡斯特大学中子实验室（Lancaster University Neutron Laboratory, LUNL）的二维SLAM地图。其中LUNL_radiation_data.txt为逗号分隔值文件，首行标注了各数据字段的类型。时间戳采用Unix纪元时间格式，符合机器人操作系统（Robot Operating System, ROS）的通用标准。机器人的空间坐标x、y、z单位均为米。由于该机器人为地面部署的二维移动机器人，SLAM估计结果限定Z轴高度大致保持恒定，因此仅需使用x与y坐标数据即可。计数数据单位为每秒计数，代表溴化铈（CeBr3）闪烁探测器与混合场分析仪在约1秒的时间窗口内采集到的辐射事件总数。地图文件（.pgm格式）为基于ROS生成的三值地图，三个取值分别对应占用区域（障碍物与墙体等物理特征）、空闲区域（自由空间）以及未知区域。地图元数据文件（.yaml格式）提供了将地图文件的像素坐标转换为米级空间坐标所需的参数。本数据集的原始数据采集于2019年12月5日，最初以ROS包（ROS bag）格式存储，经解析处理后提取为上述TXT格式数据。后续通过后处理流程，基于本数据集内的点位观测数据与配套地图文件，生成了伽马辐射的空间插值分布地图。