Investigating the capabilities of handheld LiDAR in mapping and identifying underground spaces in the urban environment

The GeoSLAM provides improved point density and accuracy, especially on building facades, but provides poor coverage of rooftops and gated areas, due to the angle of data capture. Comparison with tripod mounted terrestrial laser scanning (TLS) collected in Belfast highlights a disparity in accuracy and resolution, which the GeoSLAM makes up for with surveying efficiency.<br><br>The relationship between geographical information systems (GIS) and LiDAR data is explored and showcases the importance of GIS based datasets in organising and producing city scale LiDAR datasets.

GIS based approaches were developed to locate underground spaces within the point cloud, to promote their repetition and widespread use throughout relevant organisations. ArcGIS Pro has proven to be a suitable platform for displaying the location of basements scanned directly, indirectly and for which façade features indicate their presence.<br><br>Handheld mobile LiDAR scanning proves to fill a niche within the remote sensing market.

The hardware provides cost and time efficient data capture, inclusive of street level and underground features with resolution and accuracy great enough to enhance flood simulations. The easy deployment of the technology promotes consistent updates of digital models as the streetscape inevitably changes over time. Handheld scanning is suitable for creating a relatively inexpensive digital model or as a source of supplementary data for pre-existing topographic datasets.<br>