TY - JOUR

T1 - Ultra-rapid topographic surveying for complex environments

T2 - the hand-held mobile laser scanner (HMLS)

AU - James, Michael

AU - Quinton, John

N1 - © 2013 The Authors. Earth Surface Processes and Landforms Published by John Wiley & Sons Ltd. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

PY - 2014/1

Y1 - 2014/1

N2 - Terrestrial laser scanning is the current technique of choice for acquiring high resolution topographic data at the site scale (i.e. over tens to hundreds of metres), for accurate volume measurements or process modelling. However, in regions of complex topography with multiple local horizons, restricted lines of sight significantly hinder use of such tripod-based instruments by requiringmultiple setups to achieve full coverage of the area. We demonstrate a novel hand-held laser scanning technique that offers particular promise for site-scale topographic surveys of complex environments. To carry out a survey, the hand-held mobile laser scanner (HMLS) is walked across a site, mapping around the surveyor continuously en route.We assess the accuracy of HMLS data by comparing survey results froman eroding coastal cliff site with those acquired by a state-of-the-art terrestrial laser scanner (TLS) and also with the results of aphoto-survey, processed by structure from motion and multi-view stereo (SfM-MVS) algorithms. MHLS data are shown to have a root mean square (RMS) difference to the benchmark TLS data of 20mm, not dissimilar to that of the SfM-MVS survey (18mm). The efficiency of the HMLS system in complex terrain is demonstrated by acquiring topographic data covering ~780 m2 of salt-marsh gullies, with a mean point spacing of 4.4 cm, in approximately six minutes.We estimate that HMLS surveying of gullies is approximately 40 times fasterthan using a TLS and six times faster than using SfM-MVS.

AB - Terrestrial laser scanning is the current technique of choice for acquiring high resolution topographic data at the site scale (i.e. over tens to hundreds of metres), for accurate volume measurements or process modelling. However, in regions of complex topography with multiple local horizons, restricted lines of sight significantly hinder use of such tripod-based instruments by requiringmultiple setups to achieve full coverage of the area. We demonstrate a novel hand-held laser scanning technique that offers particular promise for site-scale topographic surveys of complex environments. To carry out a survey, the hand-held mobile laser scanner (HMLS) is walked across a site, mapping around the surveyor continuously en route.We assess the accuracy of HMLS data by comparing survey results froman eroding coastal cliff site with those acquired by a state-of-the-art terrestrial laser scanner (TLS) and also with the results of aphoto-survey, processed by structure from motion and multi-view stereo (SfM-MVS) algorithms. MHLS data are shown to have a root mean square (RMS) difference to the benchmark TLS data of 20mm, not dissimilar to that of the SfM-MVS survey (18mm). The efficiency of the HMLS system in complex terrain is demonstrated by acquiring topographic data covering ~780 m2 of salt-marsh gullies, with a mean point spacing of 4.4 cm, in approximately six minutes.We estimate that HMLS surveying of gullies is approximately 40 times fasterthan using a TLS and six times faster than using SfM-MVS.

KW - HMLS

KW - topographic survey

KW - DEM

KW - gullies

KW - laser scanning

KW - SfM-MVS

U2 - 10.1002/esp.3489

DO - 10.1002/esp.3489

M3 - Journal article

VL - 39

SP - 138

EP - 142

JO - Earth Surface Processes and Landforms

JF - Earth Surface Processes and Landforms

SN - 0197-9337

IS - 1

ER -