LiDar

Challenges and relevance of as-built documentation

There are still considerable gaps in as-built documentation in civil engineering. The plans often deviate from the actual situation in terms of position and height. This leads to costly re-measurements and delays. LiDAR (Light Detection and Ranging) is a technology that enables the rapid acquisition of millions of precise measuring points and provides a complete 3D image of the construction site in a short space of time - regardless of the light or weather conditions. The technology therefore addresses key challenges in as-built documentation and is becoming increasingly important.

Market analyses forecast growth in the global LiDAR market from around USD 1.7 billion in 2024 to over USD 3.7 billion by 2029, with an annual growth rate ofaround 18%. For the DACH region, a study estimates the market volume in 2021 at around USD 112million with an expected increase toUSD253million by 2030 . Against this backdrop, there is great potential for network operators and civil engineering companies to use LiDAR-supported documentation to make processes more efficient and safer.

2. Technological basics: How LiDAR works

Mobile LiDAR systems in civil engineering are used both on vehicles and as portable units (handheld scanners/backpacks):

• Vehicle-mounted scanners: multi-laser rotating mirror scanners such as Velodyne HDL32E or RIEGL VUX1HA generate millions of points per second and are often combined with 360° cameras.

• Handheld & backpack scanners: Devices such as Leica BLK2GO or GeoSLAM ZEB Go use SLAM algorithms and integrated IMUs for GPS-poor or confined environments.

Georeferencing is done via RTK/PPK-enabled GNSS, MEMS or FOGIMUs and an advanced Kalman filter that continuously estimates the 6D pose (position + orientation). Factory-calibrated lever arms and boresight angles as well as on-site geo-control points ensure accuracies<10cm (DIN18202:2019)

Standard workflows for data processing:

• Registration: Coarse via GNSS/IMU, precise via ICP/SLAM
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• Filtering: Removal of noise, outliers and reduction of point density.
  
  
• Modeling: Derivation of 3D meshes, profiles or BIM elements with software such as FARO Scene or Autodesk ReCap.

Digital applications in everyday civil engineering

The use of LiDAR in civil engineering is no longer limited to individual lighthouse projects. Rather, the technology has become an integral part of digital construction. Network operators, construction companies and planning offices are increasingly using LiDAR in their day-to-day business to make work processes more efficient, safer and more traceable.

A good example of this is DeepUp's solution. The portable 3D scanner and the associated web-based platform offer a complete solution for LiDAR-supported documentation in civil engineering. The scanners used are GNSS-linked and provide a georeferenced point cloud of the construction site. Site managers and planners can then use the platform to visualize and analyse this data and compare it directly with existing plans. This turns manual post-documentation into a digital and seamless workflow.

Typical fields of application:

• Pipeline cadastre: The precise recording of supply lines before and after installation facilitates subsequent maintenance work and helps to avoid damage caused by civil engineering measures. Deviations between the target and actual position are immediately visible.

• Trench monitoring: The volume calculation of excavation and filling quantities in real time enables an automated and documented mass balance. This reduces the manual effort required to determine quantities by up to 70%.

• As-built comparison: The combination of LiDAR data with BIM models enables exact target/actual comparisons in accordance with ISO19650-1. This supports quality assurance as well as billing and project approval.

A typical workflow includes:

• Planning and preparation: defining RTK base stations, control points and data formats.

• Data collection: Use of vehicle scanners on longer routes and handheld scanners in narrow trenches or areas with poor access.

• Data processing: Registration of point clouds with tools such as FARO Scene, filtering and quality control, export to common formats (e.g.LAS, E57).

• Analysis: Creation of height profiles, volume calculations, CAD floor plans or BIM models.

• Documentation: Transfer of data to existing CAD, GIS or BIM systems for further processing or archiving.

Economic and qualitative advantages

LiDAR-based 3D scanning has been proven to deliver significant efficiency gains in civil engineering by speeding up surveying processes, reducing costs and improving quality assurance. Compared to conventional methods, numerous individual measurements are no longer required, while the risk of errors is minimized thanks to seamless point clouds.

Key benefits at a glance:

• Time savings of 50-80% during measurement

• Cost reduction of 20-30% due to reduced personnel costs

• Increased accuracy(<10cm) thanks to precise georeferencing

• Less rework: up to 60% fewer corrections thanks to precise target/actual analyses

• Greater safety thanks to non-contact detection in hazardous environments

• Digital consistency: seamless workflows from the field to the planning office

This combination makes LiDAR a strategic investment for network operators and civil engineering companies that require precise as-built documentation and want to optimize their project workflows. Solutions such as those from DeepUp offer a tried-and-tested entry point with a particularly fast return on investment.

Outlook: Trends and potential

LiDAR has established itself as a key technology for precise as-built documentation in civil engineering. Future developments such as solid-state LiDAR without moving parts, higher scanner resolutions and advanced sensor fusion modules will further increase speed and cost efficiency. AI-supported algorithms for automatic classification and object recognition from point clouds are becoming increasingly important. The combination with augmented reality - as DeepUp is planning with the upcoming "DeepView" module - enables live visualizations on site and supports site managers in making decisions ("in situ"). All in all, LiDAR seamlessly integrates civil engineering into digital processes, increases transparency, improves safety and increases efficiency.