Where is the line? Augmented perception of utilities with AR and GNSS

Author: Renata Barradas Gutiérrez

Efficiently distributing electricity and natural gas through a network of 10,794.6 kilometres of overhead lines and underground cables and more than 2,000 kilometres of natural gas pipeline systems is a colossal endeavour. Vorarlberger Energienetze GmbH (vorarlberg netz), is the electricity and natural gas network grid operator maintaining this network with a high level of supply reliability and excellent service quality in Vorarlberg, the westernmost state of Austria.

Beyond the extension of the network, some of the challenges the company faces are the terrain, with two thirds of the land area in mountainous regions, and not being able to visualise the lines, as 94% of the electricity cables are underground.

“Knowing the position of these lines plays an important role in ensuring an uninterruptible supply. What sounds simple in theory often leads to challenges in practice. After completion of construction, power cables and pipelines aren’t visible on the surface. And after some time, even the most experienced employees can no longer answer the question of ‘where is the line?’” explains Sebastian Drexel, GIS administrator and developer at vorarlberg netz. “This is one of the main reasons why each line is surveyed and centrally saved within the company’s GI-system. So far, restoring lines in nature has been a time-consuming task performed by specially-trained staff.”

Visualising utilities with survey-grade accuracy in 3D

To make the task of restoring lines easier, vorarlberg netz is using state-of-the-art Augmented Reality (AR) and GNSS. AR technology superimposes digital information on an environment providing actionable information to solve problems or a specific task. Combined with GNSS, users can visualise and position utilities with survey-grade accuracy.

Digitally visualising georeferenced utilities in 3D allows vorarlberg netz field staff to intuitively experience in real-time the underground supply infrastructure and enhance natural environments via smart devices. “Our service technicians are enthusiastic about the simple and intuitive visualisation that is possible through Augmented Reality,” says Drexel.

vorarlberg netz used the Leica GG04 plus smart antenna in combination with vGIS Utilities, a utility-grade AR system for ESRI ArcGIS designed for municipalities and public utility companies. The GG04 plus smart antenna collects high-accuracy geospatial data in real time, even in the most demanding locations without the need for a mobile data connection. The antenna also pairs with all existing Leica Zeno handhelds and a wide range of Android, iOS or Windows® smart devices.

To precisely position utilities, the team uses the GG04 plus with HxGN SmartNet, the world’s largest reference network, for open-standard correction service. The integration between vGIS and GG04 plus smart antenna enables access to NMEA metadata and survey-grade, few centimetre positioning. The vorarlberg netz team quickly and easily configured the GG04 plus GNSS smart antenna to be used with vGIS on a smartphone, tablet or Microsoft HoloLens.

“We opted for the Leica GG04 plus antenna, as it is relatively low-priced, small, handy and can be coupled with mobile devices. The last of these points is crucial since the AR software runs on an Android or iOS tablet or smartphone,” explains Drexel. “The combination of vGIS and GG04 plus is recommended due to the simple setup, the connection to the mobile device, reliability and the high accuracy of the products compared to the competition.”

Applications and benefits of AR and georeferenced utilities

vGIS, paired up with GNSS, allows users to ‘see’ GIS utilities in real time through the ground. This improves situational awareness, helps to locate utilities faster, with fewer errors, and in a safe manner. vorarlberg netz is currently using AR at a pilot stage to develop the know-how, search, validate, and introduce practical applications. Currently, the company is benefiting most from four different applications:

1. Inspection of supply routes for constructions or plant coverings and location of faults along lines.
2. Restoration of lines in nature before construction activities.
3. Location of resources that are not easily visible, e.g. shut-off devices covered by gravel or snow.
4. Coordination and clarification of construction activities to external companies.

vorarlberg netz is also looking to integrate the visualisation of georeferenced utilities in combination with 3D models. The electricity and natural gas network grid operator uses a terrestrial laser scanning unit from Leica Geosystems to capture point cloud data of existing infrastructure which can further be converted to BIM models. This information is going to be the basis for the facility management, responsible for the maintenance of e.g. buildings or transformer stations.

“The use of modern BIM technologies in our company requires, in addition to the planning of new objects, the collection of inventory data using a laser scanner. In combination with 3D GIS data, this opens up new possibilities in the area of facility management and the visualisation of the digital twin with Augmented Reality,” says Andreas Mätzler, head of geoinformatics at vorarlberg netz.

Benefits of AR with GNSS for utilities include:

• Visualise GIS data in 3D on the fly to locate and find underground utilities.
• Spot faster and fix on the ground GIS data location issues, reducing collection costs.
• Improve route control for overcrowding, fouling and location of faults along cable routes.
• Simplify stakeout of cables by surveyors.
• Search and locate resources and subterranean infrastructure that are not readily visible, such as shut-off devices covered by gravel or snow.
• Improve site coordination and clarification of grave work.

Providing multiple services to transport energy and natural gas

Despite the transport of electrical energy and natural gas from the feed-in points of the transmission network by vorarlberg netz, the parent company illwerke vkw AG also performs general technical surveys, seabed surveys and engineering geodesy for tunnel advancing. For these endeavours, the company also uses Leica Geosystems solutions, including:

• Tachymeters
• GNSS receivers
• Levelling instruments
• Laser scanners

“We use Leica Geosystems products for surveying electric and gas lines as well as part of GIS services for external customers,” explains Marco Ess, head of grid- and geoinformation at vorarlberg netz.