University of Canterbury Home
    • Admin
    UC Research Repository
    UC Library
    JavaScript is disabled for your browser. Some features of this site may not work without it.
    View Item 
    1. UC Home
    2. Library
    3. UC Research Repository
    4. Faculty of Engineering | Te Kaupeka Pūhanga
    5. Engineering: Theses and Dissertations
    6. View Item
    1. UC Home
    2.  > 
    3. Library
    4.  > 
    5. UC Research Repository
    6.  > 
    7. Faculty of Engineering | Te Kaupeka Pūhanga
    8.  > 
    9. Engineering: Theses and Dissertations
    10.  > 
    11. View Item

    Towards accurate earth-referenced LiDAR mapping with an autonomous mobile robot. (2020)

    Thumbnail
    View/Open
    Young, Matthew_Final PhD Thesis.pdf (58.76Mb)
    Type of Content
    Theses / Dissertations
    UC Permalink
    https://hdl.handle.net/10092/100762
    http://dx.doi.org/10.26021/962
    
    Thesis Discipline
    Mechanical Engineering
    Degree Name
    Doctor of Philosophy
    Publisher
    University of Canterbury
    Language
    English
    Collections
    • Engineering: Theses and Dissertations [2907]
    Authors
    Young, Matthew
    show all
    Abstract

    There is enormous potential in the geospatial industry for mobile robotics to auto- mate terrain mapping. They can reduce operator-induced errors and perform tasks autonomously without supervision. This thesis seeks to quantify the accuracy and speed of an autonomous mapping robot by comparing it to conventional survey methods.

    To do this, a proof-of-concept robot was developed from a “Jackal” Unmanned Ground Vehicle (UGV), controlled by the Robot Operating System (ROS). High-accuracy GNSS, IMU and wheel encoder data was fused in an open-source Unscented Kalman Filter (UKF) to localize the robot in UTM coordinates. The ROS navigation stack was used to achieve autonomous navigation.

    This robot was used to map two sites, by measuring it’s own position as it autonomously navigated between predefined waypoints. This achieved a mean vertical accuracy of 8-17 mm, and mapped the sites in approximately 13-14 minutes. A selection of conventional GNSS RTK, total station and aerial photogrammetry methods by comparison achieved an accuracy in the range 0-70 mm, and took either a few minutes or approximately an hour to complete.

    The robot was then upgraded with a LiDAR unit, and a novel method was developed for accurately aligning and registering the scans to produce a point cloud that could be compared to one collected by a scanning total station. This method, termed Anchor Cloud Mapping (ACM) was inspired by the methods survey GNSS and total stations use for calibration. The core principles are that the robots trajectory is divided into independent sections, where the clouds in each section are registered using a keyscan, mesh-based, Generalized Iterative Closest Point method. Each cloud is then pivoted around a calibrated stationary robot pose, and aligned to best fit the UKF trajectory. When compared to a Trimble SX10 scanning total station (which is accurate to 2.5 mm), the robot/ACM cloud has a median point-to-point accuracy of 51-59 mm, and collects several times more points which are more evenly distributed throughout the environment. The robot can autonomously survey an area in minutes while the SX10 requires several hours.

    Rights
    All Right Reserved
    https://canterbury.libguides.com/rights/theses

    Related items

    Showing items related by title, author, creator and subject.

    • Accurate high-resolution 3D surface reconstruction and localisation using a wide-angle flat port underwater stereo camera: towards autonomous ship hull inspection 

      Schattschneider, Robert (University of Canterbury. Computer Science and Software Engineering, 2014)
      The goal of this thesis is to scan a ship hull with high 3D accuracy and resolution using an underwater stereo camera so as to enable the future autonomous detection of invasive biofouling organisms with autonomous underwater ...
    • Ground-based lidar processing and simulator framework for comparing models and observations (ALCF 1.0) 

      Kuma P; Morgenstern O; Querel R; Silber I; J. Flynn C; McDonald, Adrian (Copernicus GmbH, 2021)
      Automatic lidars and ceilometers (ALCs) provide valuable information on cloud and aerosols but have not been systematically used in the evaluation of general circulation models (GCMs) and numerical weather prediction (NWP) ...
    • Semi-autonomous brachiating robot for teleoperated steep terrain tree harvesting 

      Meaclem, Christopher Vincent (University of Canterbury, 2016)
      In New Zealand, the forest industry is economically significant, representing the third largest export by value. Harvesting and extraction of trees pose serious health and safety issues. These issues have become more ...
    Advanced Search

    Browse

    All of the RepositoryCommunities & CollectionsBy Issue DateAuthorsTitlesSubjectsThesis DisciplineThis CollectionBy Issue DateAuthorsTitlesSubjectsThesis Discipline

    Statistics

    View Usage Statistics
    • SUBMISSIONS
    • Research Outputs
    • UC Theses
    • CONTACTS
    • Send Feedback
    • +64 3 369 3853
    • ucresearchrepository@canterbury.ac.nz
    • ABOUT
    • UC Research Repository Guide
    • Copyright and Disclaimer
    • SUBMISSIONS
    • Research Outputs
    • UC Theses
    • CONTACTS
    • Send Feedback
    • +64 3 369 3853
    • ucresearchrepository@canterbury.ac.nz
    • ABOUT
    • UC Research Repository Guide
    • Copyright and Disclaimer