Lasergrammetric readings

Lasergrammetric readings

Lasergrammetry consists of a laser beam acquisition of points referenced in space, representative of the subject to be modeled. 3D scanners can raise several million points per second by assigning them X, Y, Z coordinates and, in some cases, RGB data from photographs taken by the hardware as well. It is therefore necessary to determine an acquisition procedure to cover the whole of a subject, in a geometrically correct and complete manner, avoiding any undercuts.

Unfortunately, it is never possible to deliver a high quality final work to the quality of a raw data set, although it is possible to improve this initial data at the cost of many hours of manual retouching or through deep learning process automation. It is on this principle that we consider it crucial to have a good knowledge of the most appropriate data acquisition and processing process aimed at improving the gross post-acquisition model.

The quality of the starting data is intrinsically linked to:

  • The quality and accuracy of the acquisition equipment,
  • Knowledge of the options and cases of use of the equipment,
  • The incidence and quality of light,
  • Knowledge of techniques and treatment programs.

All of these concurrent parameters are used to judge the quality of the raw and retouched data that will be the basis of any lasergrammetric work. The data processed can thus contribute to the elaboration of various reconstructions, both scientific and extension, depending on the final aim of the projects to which they are linked: point clouds, mesh model, file format BIM compatible, online presentation, etc…

It remains the formatting of these final data according to their usefulness, as well as their storage and classification for later reuse as the basis of other projects.

Workflow Lasergrammétrique PANORAMA

For examples of lasergrammetric achievements made by our platform, we urge you to visit our cloud of points Gallery at the address: http://panorama.ulb.ac.be/potree

In order to deliver high-precision data, PANORAMA has acquired thanks to a FNRS background a last generation laserscan FARO S-350 perfectly suitable for outdoor applications thanks to its small size, its very low weight and its high range. The FocusS 350 provides good results, even under harsh conditions, in tight, dusty or humid locations, in the rain or in direct sunlight. A compensation tool allows to optimize the quality of the data directly on site. The built-in GPS and GLONSSA receiver allow easy determination of positions. HDR imagery and HD photos ensure accurate results and high-quality data.

  • Distance accuracy at ± 1mm,
  • Range from 0.6 m to 350 m,
  • Index IP 54,
  • On-site compensation,
  • Full color HD Photo overlay up to 165 megapixels.

The lasergrammetric programs mastered by PANORAMA

In order to create different functional workflows according to many constraints due to models and computer equipment, the PANORAMA Platform team is proficient in many programs related to lasergrammetry and data processing derived from this survey method. We continue to improve our processes by continually testing the programs related to this discipline.

  • FARO scene
  • Realworks
  • Meshlab
  • CloudCompare
  • Reality capture
  • Potree converter