LASER SCANNER APPLICATION ON COMPLEX SHAPES OF ARCHITECTURE. 
PROFILES EXTRACTION PROCESSING AND 3D MODELLING. 
| Luigi FREGONESE 
Research Assegnist 
E-mail: luigi.fregonese@polimi.it 
lor Cristiana ACHILLE 
a E-mail: achillec@idraS5.iar.polimi.it 
986 3" year Course of Doctorate 
DIIAR - Department of Hydraulic, Environmental, Street Infrastructures and Survey Engineering 
cer Survey Division - Polytechnic of Milan - ITALY 
- Laboratory of "Survey, Digital Mapping and GIS” 
P.za Leonardo Da Vinci 32 - 20133 Milano - ITALY 
tel. +39 2 2399 6533 fax +39 2 2399 6550 
KEY WORD: Survey, Laser Scanner, DSM. 
  
  
  
The realization of an exhaustive model of architectural complexities requires sophisticated dedicated instruments and modelling 
surveying. 
i Latest 3D modelling tools (Alias WaveFront - Studio Tools) allow to use and to implement of realistic modelling tecniques which 
Lon deeply differ from the traditonal approach. These tools generate surfaces from clouds of points surveyed by laser technology and are 
‘leaders’ in completing the reverse engineering modelling process. The main purpose of this work is to decide if these 
y methodologies are able to 'surpass' traditional euclidean solid modelling (applied to finite elements from graphics primitives) in 
order to build a refined model of the architectural object (complex surface analysis; intelligent filtering; semiautomatic breakline; 
surface and object based on interpolation and fitting; nurbs; 3D mesh). 
jo", 
ation Of course also the problem of the metric documentation of 5 
ge Cultural and Environmental Heritage has today a great 
importance, considering also the development of new national 
= or local normative laws for protection, like risx maps for 
archaeological and artistic goods. New technologies and new 
1 techniques, that offer today high accuracy together with high 
productivity, can support new quality standards and also drive 
to set-up further refinements in the methodologies considered 
  
by these rules and laws. 
  
  
Several basic and applied researches have been carried out and 
  
terminated at a national and international level that range from 
  
  
the use of traditional surveying techniques (photogrammetry, 
  
  
  
  
remote sensing, GPS, laser scanner) to the definition of visual 
reality techniques and to the formation of relational databases Fig. 1 Laser Scanner Data (5.110.826 points). 
where, apart from the metric and representative information, 
The research it is now working on the management of point 
details fi ifferent fields of stud jated logy, : 
eis from different fields of seid are associated (geology clouds obtained from L.S.; in particular some main topics are: 
Bistory of architeecure, arcfiaeologs, eq a) the pre-treatment of data derived from average precision 
aerial and terrestrial L.S. in order to remove noise from the 
measurements and to regulate the point clouds so as to 
create three dimensional models that are useful both as a 
basis for studies founded on the finite element method and 
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