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TERRESTRIAL LIDAR FOR INDUSTRIAL METROLOGY APPLICATIONS: 
MODELLING, ENHANCEMENT AND RECONSTRUCTION 
Artur Fidera, Michael A. Chapman, Jingook Hong 
Department of Civil Engineering, Ryerson University, Toronto, CANADA 
mchapman@ryerson.ca 
Commission V, WG V/1 
KEY WORDS: Lidar, Industrial, Scanning, Accuracy Enhancement, Reconstruction 
ABSRACT: 
Time-of-flight laser scanners represent an emerging technology for capturing 3D data. They use a pulsed laser with a 
high data acquisition rate. The reflectance of surface varies by properties of materials and is an issue when scanning. 
Laboratory experiments were conducted using different types of piping materials. This paper examines the effects of 
scanning with various types of materials, which are used in industrial piping system, in terms of measurement accuracy. 
Maximum coverage angles of point clouds and diameters for each pipe are measured and compared. Application of a 
masking tape and dulling spray was found to be effective in improving the accuracy of the data. 
  
   
  
  
   
  
  
   
  
  
  
  
  
  
   
  
1. INTRODUCTION 
Over the past several years, ground-based laser scanners 
have been introduced to the area of industrial applications such 
as chemical refinery plants and piping network construction. 
Light Detection and Ranging (LiDAR) scanners measure the 
range by pulsed laser. They often employ a high-speed rotating 
mirror to scan the laser over surface of objects. 
Industrial piping systems, in general, consist of piping 
networks, which are made of various types of materials such as 
metals, steels, and PVC. The reflectance of the surface 
materials is one of the major factors to be considered in order 
to capture sufficient 3D data with a desired accuracy. 
This paper presents experimental tests of different piping 
materials and accuracy analyses based on coverage angles of 
point clouds and diameter measurements. Different types of 
media were applied to objects’ surfaces and examined to see if 
there was any improvement in the coverage angles and 
measurement accuracies. 
2. LABORATORY EXPERIMENT 
2.1 Objectives 
The purpose of these experiments is to examine the effects 
of reflecting surface materials on laser scanning measurements. 
Reflectance of surface material is an issue for scanning, and 
data capture is often impossible without sufficient laser beam 
reflection, which is sensed by a photo-detector in a scanner 
head. One of the major factors in the acquisition of field data is 
the reflectance of materials. Therefore, it is worthwhile to 
examine reflectance properties in order to acquire appropriate 
laser scanning data. 
The scanner (Cyrax 2500) uses a pulsed time-of-flight 
(TOF) laser with a wavelength of 532nm and the energy of 
laser mainly depends on physical and geometric factors. 
Physical factors can include the material’s magnetic 
permeability and electric permittivity. Geometric factors 
include the angle of incidence and roughness of the surface. In 
this experiment, geometric factors were studied by angle 
coverage observations and the alteration of the physical factors 
was studied by application of different media on the surfaces. 
For this project, the study of various materials is limited to 
specific materials used in industrial piping system such as 
brass, cast iron, aluminum, stainless steel, and PVC. However, 
extended studies of different materials can be conducted for 
other applications such as bricks, concrete, and. wooden objects, 
which are major component of buildings and urban structures. 
Observation of coverage angles and measurement of diameters 
were carried out for different materials based on their point- 
cloud data. Dulling spray and masking tape are applied to the 
surfaces as a roughness enhancing medium and the effects will 
be studied to see if there is any improvement in the data 
accuracy. The results of the study can improve the overall 
accuracy of a measurement process for applications related to 
industrial piping systems. 
2.2 Experiment Set-up 
The test field was set up in an enclosed area and the model 
space volume was approximately 2m x 2m x 2m. The test field 
was illuminated using normal fluorescent lights without any 
natural light source. The lighting conditions were uniform for 
the entire test and the temperature and humidity were normal in 
the room. There was no interference in the air such as wind or 
dust during the measurement process. 
Different types of circular-cylindrical materials were 
mounted on the table and they were aluminum, brass, cast iron, 
galvanized iron, stainless steel, glass, and PVC. The diameters 
of each object were measured by a digital caliper with the 
precision of 0.01mm. The model space and testing objects is 
shown in Figure 1. 
To quantify and analyze the effects of reflectance on different 
surface materials, the scanner stations were set Up 
approximately 2.9m from the model space. The distance from a 
laser scanner to the scanning objects was between 2.5 to 3.3m. 
The maximum coverage angle between two tangent points on a 
cylindrical object can, theoretically, be between 176° to 178° on 
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