ers (related 
anner), four 
rs (Xo, Yo, 
del, and the 
essential to 
magery. 
on the LSS 
spect to the 
1ate system, 
red. Special 
ameters, see 
| Z- axes, at 
' coordinate 
)bservations 
  
  
n to 1.95 m. 
behavior, at 
e Z-axis are 
. This may 
the relative 
1 introduced 
vements are 
etre (Figure 
/alues of the 
e. X-, Y- and 
to to 25 mm 
rom 0.25mm 
esults, using 
sth distances 
Al-Hanbali, Nedal 
(between 0.6 m and 1.25 m). Also, the relative measurements are more accurate than the absolute measurements. This is 
important since relative measurements are normally used. 
The deformation measurement results show that the calibrated parameters can be used to provide results suitable for 
industrial applications in which required precision for movements are in the order of 0.1 mm. 
  
Deformation errors 
(mm) 
| 
  
  
Figure 9: The X, Y and Z axes deformation errors calculated based on the calibrated parameters due to the introduced 
movements along the Y and Z axes at a depth distance of 1.2 m and 1.5m. 
5 CONCLUSION 
The local scaling approach can be used satisfactorily since measured precision is approximately equal to the expected 
precision of the LSS derived from the mathematical model for calibration purposes, Al-Hanbali (1998). Thus, 
deformations trends on a surface can be extracted and illustrated reliably and precisely using the local scaling approach, 
which is a simple and a quick procedure. 
The calibrated testing results show that the LSS system has better RMS values and mean errors for depth distances 
ranging from 0.6 meters up to 1.25 meters, Al-Hanbali (1998). Also, the relative measurements are more accurate than 
the absolute measurements, which is logical and it is important to be verified. 
The assessment proves that for depth distances less than 1.5 m, the LSS provides reliable and precise measurements. 
Furthermore, this demonstrates that the LSS deformation measurement precision can be satisfactorily implemented in 
industrial applications (i.e. 0.1 mm precision), thereby achieving the major objective of the DAP research. 
ACKNOWLEDGEMENT 
This paper is the result of a research project named The Dynamic Alignment Project. The motivation behind using the 
Laser Scanning System (LSS) is to develop a fast, non-contact measurement method for dynamic deformation 
monitoring. This development may complement and/or replace the state-of-the-art surveying engineering methods using 
electronic theodolite or electronic total station systems. 
The Dynamic Alignment Project (DAP), which provided the financial support for my research work, is a collaborative 
research and Development project involving the department of Geomatics Engineering at The University of Calgary, 
the Natural Science and Engineering Research Council of Canada (NSERC), the National Research Council of Canada 
(NRC), and a number of large industrial firms in Western Canada. The principle collaborating industrial partner is 
Kadon Electro Mechanical Services Ltd. of Calgary. The funding provided through the DAP by NSERC, Kadon, and 
the other industrial partners is gratefully acknowledged. 
I would like to thank the Visual Information Technology Group at the National Research Council Canada, for their 
support while I worked as a guest researcher. Special thanks and appreciation to Mr. Jacques Domey and to Mr. Marc 
Rioux, and also, to Luc Cournoyer, J.-Angelo Beraldin, and François Blais who supported me and answered my 
questions related to the Laser Scanning System technology. Furthermore, Luc Cournoyer helped us by providing his 
technical support and assistance to perform the lab tests (at The NRC labs) and the on-site test (at the Sheerness 
Generating Station) using the NRC laser scanner and his help is appreciated. 
  
International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part B5. Amsterdam 2000. 15