A Portable Scanning Solution

Background

MK Surveys, based in the UK has been using 3D laser scanners since 2002. They offer a wide range of professional measurement services including; topographical surveys, measured building surveys, mobile mapping, 3D laser scanning, BIM, 3D modelling (CAD / Revit), HDR (High Dynamic Range) imagery, utility surveys to PAS128 standard, CCTV drainage condition surveys, adoption surveys, GIS data capture and asset mapping.

Lewis Hook is a Survey Manager for MK Surveys specializing in measured building surveys, mobile mapping, LiDAR and remote sensing technologies as well as 3D modelling and visualizations for the past 3 and a half years. Prior to this, a measured building surveyor for 8 years utilizing terrestrial 3D laser scanners with the same organization whilst undertaking a part time degree in Civil Engineering Surveying following 2 years of customized in-house training and studying with The Survey Association.

Lewis commented, “MK Surveys have always been early adopters of new technologies. Our continued investment in this sector has ensured our survey teams can deliver comprehensive data with speed and accuracy whilst working safely throughout the UK and abroad.”

A Portable Scanning Solution

The company owns a wide range of 3D laser scanning hardware and software, including a mobile mapping system and recently added the latest innovation from GeoSLAM, the ZEB-REVO. This second generation, portable, handheld laser scanning device now includes a rotating sensor which eliminates the need to “rock” the device back and forth.

When asked what attracted MK Surveys to the ZEB-REVO Lewis explained, “I have seen many indoor trolley – based systems at various shows, however, they are limited with regards to their accuracy and mobility, especially between floors. The ZEB-REVO is not only fully mobile over any terrain, it also uses impressive SLAM algorithms to accurately register the scan data using the surrounding geometry.”

MK Surveys did their homework on the ZEB-REVO before making the decision to purchase.  “We purchased this new piece of equipment knowing full well after testing it that it would fit in with our day – to – day measured building surveys (mainly in the undertaking of floor plans and sections), not needing to look for alternative business applications. The accuracy of the ZEB-REVO, when used correctly ensures that our desired tolerances are met each and every time,” Lewis noted.

Applications

The primary use for the ZEB-REVO is to utilize it to measure internal building layouts – in 3D. MK Surveys have also used it to record tree positions in densely wooded areas. Lewis noted, “The typical relative accuracies we are achieving internally within a building are <5mm with the absolute accuracy over an entire floor for instance of <20mm.”

They are still recording external building footprints using terrestrial laser scanners or precise total station instruments, recording the structural openings as checks from external data to internal data. Depending on the size of the building, scan spheres are also being used throughout the main ‘spine’ of the building to ensure a full check on the registration.

MK Surveys have been thrilled with the speed and accuracy of the data collected on site. The registration process is automated and the software provides a good visual quality check by colorizing the trajectory accordingly. This must of course always be cross checked by recording check dimensions and manipulating the data if required.

Lewis noted, “All ZEB-REVO data is also checked on site by our surveyors using handheld laser distance-meters before leaving site to ensure the desired tolerances have been met.”

To digitize the scan data MK Surveys uses AutoCAD for 2D deliverables and Revit for most 3D deliverables. Lewis explained, “The scan data can be tricky to comprehend due to the range noise of the scanner, as well as the fact there are no intensity values recorded, however our surveyors have been using scan data now since the turn of the century and are all experts in this field. They are able to manipulate the data to ensure that our clients receive exactly what is required in a much more timely fashion than in the past.”

Looking Ahead

Having just invested in the ZEB-REVO, as well as a new vehicle – based, mobile mapping system MK Surveys believes that laser scanning and remote sensing methods such as structure from motion are the way survey data will be recorded for many years to come. Lewis concluded, “The acquisition of data on the move improves productivity immensely and ensures our surveyors spend less time on site in often dangerous situations.”