CSIRO Wombeyan Caves 3D Data Collection 2014 -------------------------------------------- The data included in this collection was acquired by Robert Zlot and Lukas Kaul of CSIRO at Wombeyan Caves in January 2014. The data collection includes six 3D datasets acquired and processed using CSIRO's Zebedee handheld mobile mapping system and the bentwing aerial scanning system. The results from each dataset include 3D point cloud maps of the scanned sites together with the trajectory of the scanner. For each cave that was scanned (Junction, Wollondilly, Victoria Arch), there are multiple datasets that are aligned and registered into a common coordinate frame (though these cave coordinate frames are currently not georeferenced into a global frame). Therefore, it is possible to view the registered groups of datasets for a given cave simultaneously in a viewer. The data are provided as 3D point clouds in .ply and .laz files, which are standard 3D data formats and can be opened in a number of different viewers. Some freely-available options are Meshlab and CloudCompare. .ply files can be opened in Meshlab or CloudCompare, both of which are free open-source viewers/editors available online. .laz files can be opened in a number of free and commercial software products (though not in Meshlab). MeshLab is available at http://meshlab.sourceforge.net/ CloudCompare is available at http://www.danielgm.net/cc/ Other available tools for handling las/laz files include LASTools, libLAS, and LASzip. Filenaming Convention --------------------- File Prefixes: Each filename starts with a unique prefix (including a location description and sequence number), then includes a shorthand description of the type of data included. Remainder of filename - point cloud content: The remainder of the filename describes the point cloud data properties, including subsampling, color, etc. The .ply files are primarily for visualization purposes. The .laz files contain 100% of the data points (with timestamps). Each .ply filename states the percentage of data points included (if 'pct' is in the filename) or resolution if downsampled ('cm' appears in the filename). For example 'csr02_forest_9pct' indicates that 9% of the raw data is represented, while 'csr02_forest_3cm.ply' indicates that the data has been downsampled to a 3cm resolution (technically based on a voxel grid with a random point selected as a representative in each grid cell). The .ply files also include some color (false-color) and surface information. For example, the '9pct' file is colored by height. Filenames that include the term 'shape' have had some smoothing applied to the raw points and surface normals are present. The points are colored according to local shape properties. To make use of the surface normals when viewing in Meshlab, optionally first turn off color rendering ("Render" menu at the top, then "Color->None"), then turn on lighting (lightbulb icon on toolbar), and type control-D to light from both sides. This will produce a shading based on a simulated light source. Filenames with 'traj2' show the path followed by the scanner colored according to time (blue to red). Filenames with '_traj.txt' are space-delimited ASCII text files containing the trajectory of the laser scanner as time-ordered sequence of timestamp, position (xyz), and 3D orientation (as a unit quaternion). Each row of the file contains an entry 'time x y z q0 q1 q2 q3' (where the q's are the quaternion values with scalar first). The first line of the file is a comment beginning with a '%' character indicating the format. It is assumed that the orientation of the laser scanner would likely be of little value to most end users, but is provided for completeness. For the most 'complete' form of the data (if doing more than just visualization), we recommend using the .laz and _traj.txt files, as in addition to the points and the sensor position/orientation, these contain timestamps for each measurement (which for example, allows one to associate point measurements with the position of the sensor when that measurement was taken). It is strongly recommended to maintain the full timestamp information for each point if any further processing is performed on the point clouds. Raw data is available as .bag files (not included here), and require CSIRO's processing software to convert the raw range and inertial measurements into trajectories and point clouds. Acknowledgments --------------- The data included in this data collection is copyright 2014 CSIRO and available for research and academic purposes. Please contact Robert Zlot / CSIRO to request usage for other purposes. Please credit CSIRO when using any of this data in publications or external communications (and where possible/appropriate please inform or coordinate such communications with CSIRO). The minimum requirement for acknowledgment is to state the date, location, equipment used, and technology developers (CSIRO), as in: "Data was acquired at Wombeyan Caves in January 2014 using the Zebedee 3D Mapping System and the bentwing Aerial Scanning System developed by CSIRO Australia." More information about the Zebedee 3D mapping system is available from: http://wiki.csiro.au/display/ASL/Zebedee Technical publications (pdf files) related to the Zebedee system: [1] M. Bosse, R. Zlot, and P. Flick, "Zebedee: Design of a Spring-Mounted 3-D Range Sensor with Application to Mobile Mapping", IEEE Transactions on Robotics, 28(5), pp 1104--1119, October 2012. [2] M. Bosse and R. Zlot, "Place Recognition Using Keypoint Voting in Large 3D Lidar Datasets", IEEE International Conference on Robotics and Automation, May 2013. [3] R. Zlot, M. Bosse, K. Greenop, Z. Jarzab, E. Juckes, and J. Roberts, Efficiently Capturing Large, Complex Cultural Heritage Sites with a Handheld Mobile 3D Laser Mapping System, Journal of Cultural Heritage, 2013, DOI: 10.1016/j.culher.2013.11.009. [4] R. Zlot and M. Bosse, "Efficient Large-scale Three-dimensional Mobile Mapping for Underground Mines", Journal of Field Robotics, 2014, DOI: 10.1002/rob.21504. [5] R. Zlot and M. Bosse, "Three-dimensional Mobile Mapping of Caves", Journal of Cave and Karst Studies, 2014, to appear. Please cite the Zebedee technical papers where appropriate and check first in case any of the citation details have been updated (e.g., the last two references above did not yet have page numbers at the time this document was written). CSIRO would like to acknowledge the assistance of Mike Lake, Jill Rowling, Bruce Welsh, and Rowena Larkins of the Sydney University Speleological Society, as well as the management of Wombeyan Caves. Please contact Robert.Zlot@csiro.au for further information.