Developing Method Using Field Surveying Techniques and
Instruments to Create 3D Terrain Model
Faheem Muhammad
Office of Science, Science Undergraduate Laboratory Internship (SULI)
Savannah State University
SLAC National Accelerator Laboratory
Menlo Park, CA
August 13, 2012
Prepared in partial fulfillment of the requirements of the Office of Science, Department of
Energy’s Science Undergraduate Laboratory Internship under the direction of Georg Gassner &
Catherine LeCocq at (SLAC) National Accelerator Laboratory.
Participant:
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Research Advisor:
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TABLE OF CONTENTS
Abstract
Introduction
Instruments and Method
Results
Discussion and Conclusions
Acknowledgments
ii
ABSTRACT
Developing a Method Using Field Surveying Techniques and Instruments to Create 3D Terrain
Model. FAHEEM MUHAMMAD (Savannah State University, SLAC National Accelerator
Laboratory, Menlo Park, CA 94205).
Creating a method using field surveying techniques and instruments such as
Zoller and Froehlich (Z&F) Imager 5006i 3D Laser Scanner, the Leica GPS Real Time
Kinematic System (RTK) and position targets. The software utilized are the Z&F Laser Control,
LFM Modeler, LFM Server, MicroStation V8i, Matlab, Surfer, and Arc Map to generate contour
lines to create a 3D topographic map. First I will learn techniques about how to operate the Z&F
3D Laser Scanner, the Leica GPS RTK, and the purpose of the position targets. Second the Leica
GPS RTK will be used to measure the (X,Y,Z) coordinates of selected points in my selected land
region to prepare for scans. Third perform scans at selected coordinates in order to obtain the
maximal view of the land. Fourth take scans and use computer software for image processing,
object modeling, numerical analysis and for the creation of contour lines to create the 3D
topographic map.
INTRODUCTION
The purpose of this research is to develop a method based on surveying instruments in
order to create a 3D topographic map of the SLAC facility. The instruments utilized included:
the Zoller and Froehlich (Z&F) Imager 5006i 3D Laser Scanner, the Leica GPS Real Time
Kinematic System (RTK) and the position targets. The software utilized included: the Z&F Laser
Control software, the Bentley MicroStation V8i software, LFM Server, LFM Modeller, Surfer,
Matlab, and ArcMap. Methodology included: utilizing the Leica GPS, the Z&F Imager 3D laser
scanner, Z&F Laser Control Software, LFM Server software, LFM Modeller software
MicroStation V8i software, Matlab, Surfer, and ArcMap. First utilize the Leica GPS to measure
(X, Y,Z) coordinate points for target and scanner locations in our project area. When the points
are measured the 3D laser scanner and targets will be setup and scanned around the project area.
When the area is completely scanned, scans are used in computer software to model, analyze,
register, and process scan data in order to create a 3D topographic map of project area. The
topographic map will display all the dimensions of the land and all the objects in the project area.
The main purpose of this research is to create and utilize a surveying method to create a small
topographic map of the project area. Given that this research method is successful the same
methodology will be applied to create a topographic map of the entire SLAC National
Accelerator Center facility.
Instruments & Methods
This research project purpose is to create a method by using field surveying techniques
and instruments in order to form a topographic map of the SLAC facility. The instruments that I
used for this research included the Zoller and Froehlich (Z&F) Imager 5006i 3D Laser Scanner,
the Leica GPS Real Time Kinematic System (RTK), position targets, the Z&F Laser Control
Software, the Bentley MicroStation V8i software, the LFM Modeller software, LFM Server
software Matlab, Surfer and Arc Map to generate contour lines to form a 3D
topographic map.
The Z&F 3D laser scanner is a tool that is used in the surveying field. The
Z&F uses a laser to collect data points; the laser rotates in a horizontally 360 and 310
degrees vertically at a rapid pace; The Z&F 3D Laser Scanner scans 1,016,727
Pixel/Second, can collects 800 million points per scan, reaches up to 79 meters in
distance and can complete a scan in the matter of minutes. I am using the Z&F 3D
laser scanner because it performs high resolution scans in 3 dimensions at a fast rate.
This scanner will allow me to cover a larger area in a shorter amount of time and
because of its high resolution, I can obtain high detail scans that will help me determine the
scanner location in the area I scan. [Fig1]
The rover style Leica GPS (RTK) Real Time Kinematic is an instrument that
Figure 1, Z&F 3D Laser
anner
determines the (X,Y,Z) coordinates of a point by measuring the time it takes the satellites signals
to reach the GPS receiver on earth” (1). The Leica GPS RTK improves the positioning accuracy
by comparing the signals received by a newly GPS reference station in real time. “Parker Krylon
nails” or PK nails are thick nails with indentation in the middle of its head” that is driven into the
Figure 2. Leica GPS RTK Real Time Kinematic System
asphalt, to serve as a place marker for the Leica GPS RTK
to set into when it’s time to measure the distance of the (X,
Y, Z) coordinates of a point.
In order for the scanner and scanning process to work properly 6 unknowns need to be
solved for. Three unknowns are the (X, Y, Z) coordinate position and the other three unknowns
are the 3D orientation of the scanner. We measured three points in the area for one scan to solve
for the six unknowns positions of the scanner. The Z&F scanner is set up over a point using a
tripod and then level the scanner to match the (X,Y, Z) coordinates that were measured by the
Leica GPS. We position the scanner to face an open area in the selected region of that we
thought was a good angle to capture the most area. The aim was to reduce the numbers of scans
but to capture the maximum scan area in order to attain the best view of the selected region. Next
the two targets are setup on the left and right side of the instrument to help the scanner solve for
its orientation. Also the targets are used in the registration process to serve as a detector point
for the scanner to verify its location in the scan. To register a scan means to combine one or more
scan files by position and orient all scans in a common coordinate system.
For object modeling, image processing, registration, and data analysis we uses computer
software such as the Z&F Laser Control, LFM Modeller, LFM Server, MicroStation V8i, Matlab,
Surfer, and ArcMap. The Z&F Laser Control is used for the registration of the scans from the
Z&F 3D Laser Scanner. MicroStation V8i and LFM Modeller, LFM Server, is used for object
editing, modeling, image processing, and data analysis. We use software such as Matlab, Surfer,
and ArcMap use for data analysis, image processing, test and measurements, and numerical
computation to create contour lines on the land area. Contour lines connect points of equal
elevation to visualize the height and the slope of the land area and this creates a topographic map.
The complete method that will be used for my research project includes the use of the
Leica GPS RTK, the Z&F Imager 3D laser scanner, LFM Modeller, LFM Server, Z&F Laser
Control Software, MicroStation V8i software, Matlab, SURFER, and ArcMap. We will first use
the Leica GPS to determine the (X, Y, Z) coordinate points for the Z&F 3D Laser Scanner and
the targets. We perform scans with the Z&F 3D Laser Scanner at those marked positions in the
project area. When the area is completely scanned, they are next exported to the Z&F Laser
Control for registration. After the scans are registered they are uploaded into the MicroStation
V8i software where scans can be edited and modeled. After the scans are edited, Matlab, Surfer,
or the ArcMap software is used to generate contour lines of the scanned area. The contour lines
are next put into the form of a topographic map which will display all dimensions of the land
including the roads and the location of the buildings in the selected project region.
Results
The goal of my research was to develop a method that
uses the Z&F 3D laser scanner, the Leica GPS RTK, position
targets, and Bentley MicroStation V8i, LFM Modeller, Z&F
Laser Control software, Surfer, ArcMap, and Matlab software
to generate contour lines to create a small three dimensional
topographic map of a selected region of land. [See Fig 2].The
method was successful, but the end result was not a three
dimensional topographic map. Instead the end result is a scan
overview of the selected land region. A scan overview is the
collection of 15 scans which were renamed to FM001,
FM002, FM003, FM006, FM007, FM008, FM016, FM022,
FM023, FM028, FM029, FM031, FM036, FM038, and
FM043[See Table 1]. The registered scans are compiled as
one that shows all the data points created by the scanner in
a low resolution pixilated scan photo. [See Fig 3]
Figure 3.Selected Region of Land
Scan
FM001
FM002
FM003
FM006
FM007
FM008
FM016
FM022
FM023
FM028
FM029
FM031
FM036
FM038
FM043
Easting
1849269.791
1849285.545
1849317.016
1849305.073
1849281.757
1849263.003
1849316.425
1849337.668
1849340.903
1849289.436
1849299.348
1849242.952
1849260.098
1849319.960
1849344.309
Northing
603198.861
603225.272
603233.820
603157.148
603166.417
603171.066
603215.154
603202.184
603170.952
603184.925
603203.361
603198.955
603118.534
603129.437
603155.945
Table 1 Scan Coordinate Positions
Height
96.073
94.605
92.118
91.178
91.428
93.663
91.072
90.959
91.196
91.185
91.088
95.368
95.084
95.302
95.184
Figure 3. Scan Over View
The scan overview allows
me to see the entire area in a three
dimensional aerial view. In Figure
3 shows the exact location of the
scanner positions, the area scanned,
the roads, the buildings, the trees,
and the dimensions of the land area
in
a
detailed
low
resolution
pixilated scan photo. In the scan
overview we notice two important
blind areas, where the scanner
could not collect good data points
due to bad positioning of the
scanner which resulted in a blind
spot. The first blind spot was a
portion of the parking lot that was
cut out because the Z&F 3D Laser Scanner was position in front of a trailer, and this blocked that
scanner from collecting the data on the other side of the trailer which was the parking lot. The
second blind spot is a portion of the back right hill that has fewer data points because the setup of
scanner was position at a bad angle. However the scan overview did display data points of
equally elevation in the parking lot and on the two back hills where contour lines could be
created.
Discussion & Conclusion
My initial research project was to create a method using the Zoller and Froehlich (Z&F)
Imager 5006i 3D Laser Scanner, the Leica GPS Real Time Kinematic System (RTK), position
targets, the Z&F Laser Control software, the Bentley MicroStation V8i software, LFM Modeller
software, LFM Server software, Matlab, Surfer and ArcMap to generate contour lines to form a
three dimensional topographic map of a selected land region. The end result of my research is a
three dimensional scan overview that shows the exact location of the scanner positions, the area
scanned, the roads, the buildings, the trees, and the dimensions of the land area in a detailed low
resolution pixilated scan photo. The scan overview also displays data points of the selected land
region that can be used to create contour lines which can be formed into a three dimensional
topographic map. We were not able to process where contours lines because of time. In order to
create the contour lines for the scans, the buildings needed to be excluded from the scan so that
the contour lines won’t be mapped on the buildings, but only map on the grass and asphalt to
show all the different elevations of the land the project area. [See Fig 3.] For future research this
method of surveying could be used to create a 3D topographic which is useful to engineers,
because it provides full detail layout of a land region in three dimensions, which highlights the
different elevations in that land region. The map can be determine how, where and what can
build in the land.
Acknowledgements
I would like to thank the Department of Energy for providing the Summer Undergraduate
Laboratory Internship (SULI). I would also like to that the SLAC National Accelerator Center
for being the host laboratory for the research I conducted. I would also like to thank my mentors
Georg Gassner and Catherine LeCocq for providing interesting research and for selecting me to
work with the Alignment Engineering Team at SLAC. I would also like to thank Michael
Gaydosh and Hans Imfield for teaching me how to use the instruments.
Reference Page
(1)GPS Basics, Introduction to GPS (Global Positioning Systems) Version 1.0. Switzerland: Leica, 1999.