Phone Email

Technology and equipment: which method when

No single method can do everything. A terrestrial scanner sees details a drone never sees; a drone sees a roof no tripod can reach. Which instrument is used is decided not by the equipment available but by the task. This page names both: what we have and how we decide.

What we work with

Mobile laser scanners, a FARO Focus on its tripod and the drone: the equipment we survey with.

Zwei Mitarbeiter mit mobilen Laserscannern, dazwischen ein FARO Focus auf dem Stativ, darüber eine Drohne in der Luft

Terrestrial laser scanning

Instrument: FARO Focus Premium. Accuracy: below 1 cm, sufficient for detailed design and connection planning.

The scanner stands on a tripod and measures what it sees from each station. What it does not see does not exist in the capture — which is why the number of stations determines completeness, not the resolution of the instrument.

When it is the right method: when construction is based on the capture. Connection points, façade details, structural framework, plant rooms with dense geometry. Wherever a centimetre of deviation means rework on site.

Mobile mapping

Instruments: NavVis VLX and NavVis MLX. Output: more than 8,000 m² per day possible.

A wearable scanner that measures while you walk. No tripod, no station changes, no interruption to operations. For large areas it is many times superior to the tripod — not because it is more accurate, but because it manages in one day what the scanner needs a week for.

When it is the right method: floor areas, long corridors, building stocks across several buildings, surveys during ongoing operation. In short: wherever the area is the problem and not the detail.

Drone and photogrammetry

Instrument: DJI Matrice 4E. Use: roof, façade and terrain.

From overlapping aerial images, photogrammetry computes a point cloud and from it orthophotos and terrain and surface models. The advantage lies not in accuracy but in reach: a roof without scaffolding, a façade without an aerial work platform, a site without walking it.

When the drone is the wrong choice — and we state this deliberately, because nobody else does: no terrain model can be produced under vegetation. The camera sees leaves, not the ground beneath them. What you get is a surface model (DSM), and anyone who needs a terrain model (DTM) then needs a different method or a different date in winter.

GNSS and control points

Instrument: Emlid. Reference systems: ETRS89/UTM for position, DHHN2016 for height.

A capture without a spatial reference is a model floating in a vacuum. It can be evaluated in itself, but it cannot be combined with a cadastral plan, a neighbouring building or a second capture. Control points establish this reference — why this is not a formality is explained in the glossary entry georeferencing.

Which method when

The decision is made by the task, not by the building type:

  • Construction will be based on it → terrestrial scan. The centimetre counts.
  • It is about areas and operation → mobile mapping. The area counts.
  • It is high up or outdoors → drone. Reach counts.
  • It has to fit with other data → GNSS control points, in addition to one of the three.

In most projects it is not one method but a combination: envelope by terrestrial scanning, interiors by mobile mapping, roof by drone, everything tied to a common system via control points. That is one appointment and one point cloud, not three projects.

Further information