Embed Size (px)
Citation preview
1385 Woodroffe Ave.
Ottawa, Ontario
K2G 1V8
October 27, 2015
Mr. Patrick Dawson
1385 Woodroffe Ave.
Ottawa, Ontario
K2G 1V8
Dear Mr. Dawson:
Kindly find attached our report entitled “Investigating Geographic Information System
Technologies: A Global Positioning System Jobsite Calibration for the City of Ottawa.” We
submit this report as one of many requirements for our diplomas in Civil Engineering
Technology at Algonquin College.
This report comprises five chapters. The first chapter is an introduction, which provides
background information regarding the technological concepts involved in the system we created.
It also describes the motivation behind the project along with its scope and limitations. Next, the
second chapter outlines the process we followed in designing and creating our calibration file.
The third chapter provides the methodology that we followed to test our system and chapter four
is a summary of the analysis of the testing results. Finally, the fifth chapter is a conclusion
providing recommendations and a discussion explaining and justifying these recommendations.
Hopefully this report helps you to gain some insight into the ideas we have entertained over the
past ten months. We thank you for the guidance and input you provided in compiling this report.
The research and writing processes involved in this report were both demanding and time-
consuming, but they were great preparation for our careers moving forward. Thank you for the
opportunity.
Sincerely,
Ronald Darraugh Brandon Nussey Simon Sweeney Bryan Dewar
Attached: Technology report
Investigating Geographic Information System Technologies: A Global
Positioning System Jobsite Calibration for the City of Ottawa
Ronald Darraugh
040 744 459
Brandon Nussey
040 752 041
Simon Sweeney
040 752 162
Bryan Dewar
040 633 694
Algonquin College
Civil Engineering Technology
Algonquin Centre for Construction Excellence
Tuesday, October 27, 2015
A technology report submitted to Professor Patrick Dawson in partial fulfillment of the
requirements for a diploma in Civil Engineering Technology
Summary
In this report a practical investigation of a commonly used application of Geographic
Information Systems: a Global Positioning System (GPS) surveying kit; was completed. More
specifically, it includes a description of how a digital file was created. This digital file can be
used in combination with a GPS kit, and standard digital construction drawings in order to
localize or calibrate a site remotely. The system was evaluated based on its degree of accuracy.
The topic was explored at the request of an industry with the use of many of their resources, in
an attempt to minimize surveying and labour expenses. This report offers a potential means of
cutting down on survey expenses and accelerating contract schedules.
The report is broken down into five individual chapters. The first chapter introduces the topic
and provides some background information describing GPS technology and its common
applications. The second chapter provides more complete and specific details as to how the
digital calibration file was designed and created. In the third chapter, the two testing methods
used to measure the accuracy of the system are described. In the fourth chapter, the test results
are analyzed. The last chapter reflects on the success of the system and makes recommendations
and then thoroughly discusses the reasons for them. It is concluded that this project creates an
innovative improvement for jobsite calibration and can be used in many productive manners. It is
recommended that the industry partner use the digital calibration file.
It was decided that since the level of accuracy is well within industry standards for many
construction activities, the use of this file can save many hours of survey and labour work. The
calibration file that was created is not only accurate, but based on testing, appears to provide data
that is less distorted and reaches a wider scope than the individual files currently in use.
Although the system will need some double checking, it can be used as a very strong starting
point for many contracts.
Table of Contents
List of Illustrations ...........................................................................................................................v
Glossary ......................................................................................................................................... vi
Symbols......................................................................................................................................... vii
Chapter Page
1.0 Introduction ..............................................................................................................................1
2.0 Design ........................................................................................................................................8
2.1 Control Network ............................................................................................................8
2.2 Calibration Geometry.....................................................................................................8
2.3 Procedure .....................................................................................................................10
3.0 Methodology ...........................................................................................................................12
3.1 Practical Test ................................................................................................................12
3.2 Digital Test...................................................................................................................13
4.0 Analysis of Results .................................................................................................................14
4.1 Practical Test Results ...................................................................................................14
4.2 Digital Test Results ......................................................................................................15
5.0 Conclusion ..............................................................................................................................18
5.1 Review .........................................................................................................................18
5.2 Recommendations ........................................................................................................19
Works Cited ............................................................................................................................21
Appendices ..............................................................................................................................22
Appendix A: Typical survey control monument installation schematic ......................22
Appendix B: Control monument report from Ontario COSINE database ..................23
Appendix C: Full practical testing results ....................................................................24
Appendix D: Full digital testing results .......................................................................25
List of Illustrations
Figure Page
1. The basic concept of GIS software. ........................................................................................................ 1
2. A ripped orange peel representing data transfer distortion . ................................................................... 3
3. A typical survey control monument in the field . ................................................................................... 4
4. Effective geospatial range of IBSS base station used for the creation of the geographic localization
reference system . ................................................................................................................................... 7
5. Good calibration geometry . ................................................................................................................... 9
6. Bad calibration geometry . ..................................................................................................................... 9
7. Achieved calibration geometry . ........................................................................................................... 10
8. A Trimble site calibration computation report . ................................................................................... 13
Table Page
I. Practical testing results showing average measured deviations from theoretical values. .................. 14
II. Individual job site calibration computation results showing scale factors, rotation angles, and
maximum horizontal and vertical residuals. ...................................................................................... 15
v
Glossary of Terms
AutoCAD ...............................computer software used in the design and drafting of construction
drawings
Calibration .............................the process of providing real world, site specific, geographic data
to a GNSS; the same as localization
Calibration geometry .............the usable area resulting from the shape created by the baselines
connecting the control points used in a calibration
Coordinate system ..................the collection of numbers and labels that describe positional
information of a feature
Easting ...................................horizontal coordinate running along x-axis
Elevation ................................vertical coordinate running along z-axis
Extrapolation .........................process of estimating data outside of a range of measured values
Geodetic .................................an adjective referring to the science of dividing and measuring the
Earth, geodesy
GPS survey kit ........................a combination of a base and rover that connects to satellite
networks to provide survey capabilities
Interpolation ..........................process of estimating data inside of a range of measured values
Localization............................ the process of providing real world, site specific, geographic data
to a GNSS; the same as calibration
Northing .................................horizontal coordinate running along y-axis
Survey control ........................reference points of known northing, easting, and elevation
vi
Symbols
°,’,” ............................................................................................. angular degrees, minutes, seconds
∆ ............................................................................................................................. delta or ‘change’
m ............................................................................................................................................. metres
mm .................................................................................................................................. millimetres
+/- ................................................................................................................................. plus or minus
2-D .......................................................................................................................... two-dimensional
3-D ........................................................................................................................ three-dimensional
GIS ................................................................................................. Geographic Information System
GNSS ......................................................................................... Global Navigation Satellite System
GPS ......................................................................................................... Global Positioning System
IBSS ..................................................................................................... Internet Base Station Service
MTM ................................................................................................ Modified Transverse Mercator
SCS ............................................................................................................. Site Controller Software
vii
1
1.0 – Introduction
A geographic localization reference system is created and evaluated for accuracy in order to
improve the process of localizing individual construction job sites within the city of Ottawa.
A Geographical Information System (GIS) is essentially “a system for marrying data sets with
geography” [1]. Systems of this nature allow people to digitally layer multiple sources of
information onto maps and use them as a tool for planning and building. For example, GIS
software has the ability to combine data types such as imagery, geographic coordinates,
elevation, and survey control into a comprehensive, working model that can then be used for
construction processes such as laying out site features including building foundations and
utilities. Figure 1 shows the basic idea behind GIS software.
Figure 1. The basic concept of GIS software [2].
The curved, three dimensional surface of the Earth is often represented in two dimensional media
such as maps or construction drawings both for illustrative and construction designing purposes.
2
The computer program AutoCAD is generally accepted as the construction industry’s standard
for preparing these types of drawings and plans. These drawings may be printed for use or
perhaps adapted in a digital format to be used in conjunction with a geographic information
system software program. The function of these types of software is to accurately represent and
build designs for construction projects using actual, geodetically sound coordinates for reference
and have these designs built accordingly.
An example of a common coordinate system used to model three-dimensional surfaces as two-
dimensional representations is the Modified Transverse Mercator (MTM) coordinate system.
Distortion of information is an unfortunate by-product of this type of data transfer. Figure 2
shows a common analogy for the distortion of information created by data transfer. If the Earth’s
surface is imagined as an orange peel, laid out on a flat surface such as a table or piece of paper,
it would be effectively impossible for the orange to be displayed as it once was. The peel of the
orange has been ripped and when placed on the paper it has bulges and wrinkles in its shape.
These rips, bulges, and wrinkles represent the distortion of information that is created during a
transfer from a 3-D reality to a 2-D medium.
3
Figure 2. A ripped orange peel representing data transfer distortion [3].
Mitigation of the distortion of information is attempted by various means. A common industry
practice is to localize individual job sites to link theoretical coordinates to real, physical locations
on the Earth. If the theoretical coordinates are imagined to be similar to those used in the board
game Battleship, one cannot walk around and find these coordinates labeled anywhere. In order
to use these coordinates practically without distortion of data, there must be some input of real
values into the system. The process of localizing or calibrating the City of Ottawa as if it were
one large jobsite provides this input of real world data in an attempt to ‘iron out the wrinkles’ in
the orange peel by providing data that represents the ground surface. This process is completed
by measuring the three-dimensional position of points with known coordinates, such as survey
control monuments, and giving theoretical coordinates a real position on the ground. As a result,
after calibration, the GPS base and rover system can be used to locate arbitrary site features that
have theoretical geographic coordinates. Figure 3 illustrates how a typical survey control
monument might appear in the field.
4
Figure 3. A typical survey control monument in the field [4].
For a more comprehensive diagram of a survey control monument with specifications, please see
Appendix A. This localization process can be completed with the application of a common GIS
technology: a global positioning system (GPS) device. A GPS base station and rover kit
combination connect to a network of satellites to precisely triangulate position and height within
a given coordinate system. There are two common types of base stations that are used. A
common practice is to set up an individual local base station on a job site and use it to
communicate corrections to a rover in the field. Local bases transmit corrections to the rover via
a radio signal and can cover circular areas of with 2 to 3 kilometer radiuses, centred on the base
station itself. This type of base station has limitations. The industry partner’s equipment includes
a more effective base station type: an Internet Base Station Service (IBSS). An IBSS can
communicate via internet connections through cellular networks resulting in increased effective
ranges of coverage. Typically, the effective range of an IBSS base is a circular area of
approximately 30 kilometres centred on the base station’s location. The immediately obvious
5
advantage of an IBSS base station is an increased range of coverage. This allows a single base to
provide corrections to multiple rover kits on multiple job sites as opposed to setting up individual
local base stations on singular sites. However, an IBSS base station does not eliminate the need
to localize job sites, effectively ‘tying’ or ‘pinning’ their specific, individual plans down to the
ground.
The idea behind this investigation is to localize the entire city of Ottawa as if it were one large,
comprehensive jobsite in order to create a city-wide calibration file. If done correctly, this could
effectively eliminate the need to calibrate individual job sites. The potential for savings on labour
intensive and time consuming localizations is a very interesting and challenging area to explore.
A city-wide calibration has the potential to be an incredibly useful tool for localizing individual
construction job sites. However, this type of tool must meet certain requirements in order to be
feasible and worthwhile. For example, the system must maintain a high degree of effective
accuracy. Therefore, it is logical to examine such a system based on accuracy, which is defined
below.
Accuracy is defined in metres and reflects the repeatability of precise measurements and the
location of features within the typical range of tolerance deemed acceptable by industry
standards. For many rough construction activities, +/- 1-50mm is acceptable.
This report comprises five chapters. Following this introduction, Chapter 2 provides detailed
description of the processes involved in creating the digital calibration file. Chapter 3 provides a
detailed description of the methodology used to test the accuracy of the system and Chapter 4
summarizes the analysis of test results. Finally, Chapter 5 recommends the implementation of the
system and discusses why this recommendation is made.
6
Readers of this report will gain an understanding of the discipline of geodesy which encompasses
major concepts that are used every day in common technologies. For example, global
navigational satellite systems (GNSSs), which allow us electronic location of various points of
interest on the surface of the planet, would not be possible without the framework set in place by
geodesy. The subject of geodesy includes concepts such as geographic coordinate systems, map
projections, datums, geoid models, and traditional land surveying methods. This report will be of
interest to anyone who is geodetically inclined, including land surveyors, cartographers,
construction companies and workers, and geographic information system technicians. An
understanding of the information presented in this report provides readers with an introduction to
the concepts involved in map making, global positioning system (GPS) devices, and land
surveying techniques.
The scope of this report has actual physical and spatial limitations. The idea is to set up an
internet base station service (IBSS), with an effective communication range of 30 kilometres,
and use this base station to localize multiple jobsites within its range. Local base stations that use
radio signal to communicate corrections are excluded from the project as their effective range of
coverage is too small. Also, this is not the type of base station that will be used in the creation of
the system and thus it makes sense to exclude it from the investigation. Due to the range limits of
the base station being used, a circular area with a radius of 30 km, centred on the base’s location
is the spatial limit of the system. This area encompasses most of the city of Ottawa and so that is
what is considered to be the scope of the project. Figure 4 shows the spatial extent of the
effective range of the IBSS base station.
7
Figure 4. Effective geospatial range of IBSS base station used for the creation of the geographic localization reference system [5].
8
2.0 – Design
2.1 – Control Network
In order to perform the Ottawa-wide localization, also referred as a calibration, a network of
reliable survey control points needed to be obtained from which to measure and record
coordinate data. Information was gathered from a combination of the following sources: the
National Resources Canada online database, the Ontario Government’s Control Survey
Information Network Exchange (COSINE) online database, and City of Ottawa survey control
monuments obtained from the Ottawa Light Rail Transit project. Appendix B provides an
example of a control point report from the COSINE database.
2.2 – Calibration Geometry
The points needed to surround the city in order to ensure effective calibration geometry. For GPS
survey work, a good practice for creating effective calibration geometry is to use points around
the perimeter of the geographical area being calibrated. The reasoning for choosing points
around the perimeter of the intended area of calibration involves basic data principles.
Interpolation is a standard practice used to make predictions about intermediate points within any
measured range of data. Extrapolation involves trying to make predictions using the same data,
but outside the range of measured points. When extrapolation is attempted, the accuracy and
reliability of data is unknown. Good calibration geometry requires the application of the
principles of interpolation and extrapolation. The area created between the control points
measured in the calibration process can be considered to represent an area where reliable
interpolation can be done. Ideally, a properly calibrated jobsite should fall entirely within this
area. Figure 5 shows an example of desirable calibration geometry.
9
Figure 5. Good calibration geometry [6].
Anywhere within the calibrated area can be trusted, provided it meets required testing
parameters. Any area outside this range would require extrapolation of data which could lead to
errors. Figure 6 illustrates poor calibration geometry.
Figure 6. Bad calibration geometry [6].
10
Therefore, in order for the calibration to be effective across the city of Ottawa, the control points
measured in the calibration should surround the city as completely as possible. Figure 7 shows
the calibration geometry that was targeted.
Figure 7. Achieved calibration geometry [5].
2.3 - Procedure
The control points that were selected were found in the form: Northing, Easting, and Elevation.
The next step was to take this data and enter it into a rover kit’s data collector unit. A Trimble
GPS base and rover with its Site Controller Software SCS Version 3.4 was used. This software
allows the creation of a digital jobsite which can include a design in the form of AutoCAD line
work, three dimensional models of structures, and control points to use in site localization. The
control points were entered into the data collector manually using its key pad. Once control point
information was entered, the rover was setup by connecting it to the base. After opening a newly
11
created job file, chosen settings included using a published coordinate system relevant to this
part of Ontario: MTM Zone 9. The Canadian Geoid Model HT2 was also chosen. Upon choosing
these settings and entering the list of control points, the software then notifies the user that it is
using a published coordinate system and asks if the user would like to adjust it with a site
calibration. If not, the GPS rover can locate features of known coordinates within roughly one to
two metres. This degree of accuracy is not close enough to use for building and for this reason, a
site calibration must be performed. However, the one to two metre range of accuracy is good
enough to use to roughly locate the control points.
After this preliminary research and setup, the next steps were to go out and find these points and
measure their position, horizontally and vertically, to adjust the published coordinates with a site
calibration. Once a point is located, the rover kit is set up with a two-metre rod and support bipod
on the control point, as plumb as possible using a fish eye level. Then, using the software
options, the time taken to measure the point is chosen. The longer the points are measured, the
more accurate and precise the measurements will be. With this in mind, it was chosen to measure
each point for ten minutes. After all of the points were measured and satisfactory calibration
geometry was achieved, the site calibration was complete.
12
3.0 – Methodology
In order to determine the accuracy of the calibration, two tests were performed: a practical test
and a digital test. The practical test had a process similar to the creation of the system. The
digital test involved using the GPS software to analyze and compare the results of the city-wide
calibration with those of the individual site calibrations.
3.1 – Practical Test
The practical test involved creating a job file with the new calibration and using it to locate site
features. In an attempt to test the system objectively, the survey control points measured as part
of the testing phase were not any of the points used in the creation phase of the system. This tests
the ability of the new calibration to accurately locate arbitrary features. This test was completed
by adding control points to a newly created job file, connecting the rover kit to the base station,
and then rechecking the system setup by measuring the coordinate values of control points. The
GPS rover kit was set up on arbitrarily selected control points and allowed to measure data for
one minute. After the coordinate measurement, the software on the data collector informs the
user whether or not the measured values fall where they should in relation to their theoretical
coordinates and the measured values of the calibration’s original control points, within
predetermined ranges of tolerance. The range of horizontal and vertical tolerance chosen was +/-
50 mm. Ten different control points from the City of Ottawa survey control network were
measured four times each. The software also shows the user the difference between theoretical
and measured northing, easting, and elevation values as an indication of the accuracy achieved in
each respective category.
13
3.2 – Digital Test
The digital test forms a basis for comparison of the city-wide calibration with individual jobsite
calibrations. This test is a feature that is available as part of the Trimble software, which
compares the geometry of the measured area to a theoretical model. After any calibration is
completed, an option becomes available to view a report of computed calibration results. These
include the measured horizontal scale factor, horizontal rotation angle, and maximum horizontal
and vertical residuals. The residuals are the theoretical control point values subtracted from the
measured values. Figure 8 shows an example of a calibration computation report done using the
software.
Figure 8. A Trimble site calibration computation report [7].
This site calibration computation test was run on the city-wide calibration as well as 35 jobsites
that were calibrated individually in order to compare values.
14
4.0 – Analysis of Results
The two methods of testing the city-wide calibration were done for different reasons to determine
different parameters. The practical test is essentially an experimentation of the calibration file,
done in order to measure its ability to locate site features accurately. The digital test provides
information which can be used to make theoretical evaluations of the quality of calibration files.
4.1 – Practical Test Results
The practical test is important because it determines whether or not the city-wide calibration is
usable and reliable. It is a good field test of how accurately the calibration will be able to layout
site features such as curbs or sewers. If the calibration can consistently locate features within +/-
1-50mm, then it can be used with confidence for many construction applications. The results of
the practical testing were recorded and are shown in Table I.
Table I. Practical testing results showing average measured deviations from theoretical values.
Point ∆ Northing (m) ∆ Easting (m) ∆ Elevation (m)
168 0.042 0.013 0.026
142 0.050 0.009 0.038
143 0.032 0.020 0.010
145 0.035 0.002 0.010
73 0.055 0.036 0.049
3 0.014 0.021 0.014
170 0.050 0.003 0.011
171 0.042 0.005 0.012
59 0.037 0.005 0.008
173 0.036 0.008 0.014
Average= 0.039 0.012 0.019
15
The results of the practical testing show that the city-wide calibration is capable of locating
points, both horizontally and vertically, within the desired accuracy range of +/- 1-50 mm. This
means that if this calibration is used, the user can be confident they will be able to locate and lay
out construction site features within this range. There are many applications where this accuracy
range is deemed tolerable. For example, tasks such as stripping topsoil, installing silt fencing,
and roadway embankment excavation typically allow accuracy within +/-50mm. This means that
the city-wide calibration could be used to carry out these tasks with no significant issues. The
results of this practical testing show that the city-wide calibration is accurate.
4.2 – Digital Test Results
The digital testing that was performed provides information about the theoretical quality of
calibration files. The test itself computes the transformations resulting from assigning theoretical
coordinate values to real locations measured on the ground. The values that this test gives
include scale factors, rotation angles, and maximum vertical and horizontal residuals. The results
of the digital testing were recorded and are shown in Table II.
Table II. Individual job site calibration computation results showing scale factors, rotation angles, and maximum horizontal and vertical residuals.
Job Scale Factor
Rotation
Angle (°,',") Horizontal
Residual (m) Vertical
Residual (m)
∆ Scale
Factor
∆ per
100m (m) ∆ per
1000m (m)
Individual site average 0.999914835 0° 33' 52.3" 0.020 0.036 0.0001068955 0.01068954 0.1068954
City-wide calibration 0.999996488 0° 00' 1.0" 0.017 0.007 0.0000035118 0.00035118 0.0035118
16
The scale factor and rotation angle values reflect how much the software needed to change the
original AutoCAD design in order for the theoretical geometry of the site and ground coordinates
to align properly. Using the orange peel analogy, this is the process of ironing out the wrinkles
and thus mitigating transformation distortion. The more that the scale factor deviates from a
value of 1 and the higher the rotation angle, the less accurate the calibration will be. Any
potential inaccuracy of the device is compounded by the scale factor. When extrapolated over
given distances, the changes in scale factor and rotation angle show an approximation of the
potential inaccuracy. For example, the average individual site calibration scale factor was found
to be 0.999914835. This means that for a site with a 1000m radius, the scaling of the design
could lead a person using the calibration to layout a site feature at the extent of the site
incorrectly, by as far off as 106.9mm. This degree of error could lead to potential costly
mistakes. The city-wide calibration resulted in a scale factor of 0.999996488. Considering the
same site with a 1000m radius, the scaling of the design in this case would lead to an error of no
more than 3.5mm. When applied to even larger sites, the error becomes cumulative as the size of
the site increases. Therefore, it is critical to achieve a scale factor that is a close to 1 as possible.
Smaller rotation angles are also desirable as they transform the data less. The results of the
digital testing show that the city-wide calibration creates better scale factors and rotation angles
than individual site calibrations, on average.
The horizontal and vertical residual values reflect the accuracy of the measured values from a
site calibration. Generally, it has been observed that as the time of measurement of control points
during calibration increases, the residuals decrease. This has an impact on the accuracy of the
calibration as well. Smaller residual values positively impact the scale factors and rotation angle
that result from computing the site. As a result, smaller residual values reflect more accurate
17
sites. The digital testing showed that the city-wide calibration had smaller horizontal and vertical
residuals than average individual sites. This means that the city-wide calibration will create less
transformation than the individual site calibrations and is more accurate and reliable.
18
5.0 – Conclusion
It is concluded that the digital calibration file created in this project provides an innovative,
accurate, and effective solution for the process of calibrating individual job sites.
5.1 - Review
This report investigates a common application of Geographic Information System technology.
More specifically, the creation of a usable digital jobsite calibration file for the City of Ottawa is
outlined. The way this file can be used in combination with a Global Positioning System survey
kit is also explained. Two test methods were carried out: one practical and one theoretical. The
test results are included and analyzed regarding the overall accuracy of the calibration. This
project was performed at the request of an industry partner, a local civil construction company.
The intended goal of this project was to create a calibration file that can be used for contracts in
the City of Ottawa, eliminating the need to calibrate individual job sites. If successful, this file
has the potential to save many hours of surveying and labour.
The analysis informs the recommendation that the digital calibration file be used. The calibration
geometry achieved suggests that it is capable of covering most of the City of Ottawa. As the
company that it was created for takes on a large number of contracts in the city, the calibration
file has multiple future benefits.
The calibration file that was created needed to be accurate, first and foremost. The desired degree
of accuracy was within the range of +/- 1-50mm. The practical testing that was carried out
showed that the created file was capable of achieving this accuracy range. In fact, the average
19
distance of uncertainty that was determined through practical testing was found to be 39mm in
Northing, 12mm in Easting, and 19mm in elevation.
The digital testing of the theoretical accuracy of the calibration file produced a scale factor of
0.999996488 as compared to average individual site calibrations which had a scale factor of
0.999914835. This means that over given distances, digital designs will be distorted less using
the city-wide calibration. For example, across 1000m of space on a job site, the average
individual site calibration scale factor would result in a compounded distortion error of
106.9mm. Over the same 1000m job site, the new city-wide calibration would result in only
3.5mm of similar error. The digital testing also gave an indication of the rotation angle resulting
from the calibration. In the case of the individual site calibrations, the average rotation angle was
0° 33' 52.3", whereas the city-wide calibration showed rotation by only 0° 00' 1.0". A smaller
rotation angle means less transformation of original design data and thus the digital jobsite
design will be closer to the intended design.
5.2 - Recommendations
Based on the accuracy of the new calibration file, as well as its potential for eliminating many
hours of labour and survey work, it is recommended that the file be implemented by the industry
partner. In order to confirm that the file is reliable, further testing would need to be done. This
might include implementing the calibration on a given site and measuring existing features to
continue the practical testing phase. However, without any further testing, the calibration file
already has the capability of providing accurate information for many rough construction
processes. For example, tasks such as stripping topsoil, laying out job site limits, and laying out
various types of construction fencing can all be done reliably with the calibration file as it exists
20
presently. This can allow the company to start rough work before calibrating the site,
accelerating contract schedules. Furthermore, if the calibration is tested on a site and found not to
be accurate enough for some applications like fine grading granular materials, and an individual
site calibration is still necessary, the city-wide calibration can be used to aid the process. The
city-wide calibration has the ability to locate arbitrary points with known coordinates within +/-
1-50mm and so it would be a great tool for locating control points inside its area of spatial
coverage.
Throughout the creation phase of this project, the digital file was saved after measuring each
control point. This means the potential exists for future modification of the file. This
modification could include re-measuring some of the control points in an attempt to achieve
lower residuals and thus a more accurate calibration. It may also include measuring more control
points around the city in an attempt to broaden the effective range of the calibration. Regardless
of any future modifications, the new calibration file achieved the desired outcomes and is a
useful tool that can be used for multiple productive applications.
21
Works Cited
[1] J. C. Aguirre, "The Unlikely History of the Origins of Modern Maps," Smithsonian.com, 14 June 2014.
[Online]. Available: http://www.smithsonianmag.com/history/unlikely-history-origins-modern-maps-
180951617/?no-ist. [Accessed 18 February 2015].
[2] Henrico County GIS Office, "Geographic Information Systems," Henrico County, Virginia, 25 March
2015. [Online]. Available: http://henrico.us/gis/. [Accessed 25 March 2015].
[3] J. B. Krygier, "Geography 353 Cartography and Visualization," Ohio Wesleyan University, 10 May
2014. [Online]. Available:
http://krygier.owu.edu/krygier_html/geog_353/geog_353_lo/geog_353_lo05.html. [Accessed 25
March 2015].
[4] K. Shipley, "Okinawa," Land Surveyors United, 6 September 2012. [Online]. Available:
http://landsurveyorsunited.com/photo/okinawa?xg_source=activity. [Accessed 25 March 2015].
[5] "Ottawa 5003553.63m N and 445777.46m E," Google Earth, 4 September 2013. [Online]. [Accessed
26 October 2015].
[6] R. Darraugh, "GPS Basics," Ottawa, 2015.
[7] Trimble Navigation, "Trimble Site Controller Software Version 3.41," Trimble Navigation Limited,
Sunnyvale, 2015.
[8] State of New Jersey Department of Transportation, "Minimum Guidelines for Aerial
Photogrammertic Mapping (Metric)," State of New Jersey Department of Transportation, 19 March
2009. [Online]. Available:
http://www.state.nj.us/transportation/eng/documents/photogrammetry/Section4.htm. [Accessed
25 March 2015].
[9] Ministry of Natural Resources, "COSINE Online Service Retrieval Home Page," Government of
Ontario, 19 October 2015. [Online]. Available: http://www.applications.lrc.gov.on.ca/cosine/cgi-
bin/COSN_RetrFuncts.asp?task=gen_homepage. [Accessed 10 March 2015].
22
Appendix A – Typical survey control monument installation schematic [8].
23
Appendix B – Typical survey control monument report from Ontario COSINE database [9].
24
Appendix C – Full practical testing results.
Point ∆ Northing (m) ∆ Easting (m) ∆ Elevation (m)
168 0.070 0.033 0.066
0.036 0.003 0.007
0.030 0.011 0.012
0.031 0.005 0.017
142 0.045 0.001 0.020
0.048 0.020 0.078
0.052 0.013 0.048
0.055 0.000 0.006
143 0.038 0.016 0.011
0.013 0.021 0.024
0.042 0.021 0.004
0.035 0.020 0.000
145 0.032 0.001 0.012
0.032 0.001 0.003
0.031 0.004 0.019
0.043 0.003 0.004
73 0.030 0.010 0.059
0.051 0.025 0.023
0.052 0.054 0.051
0.085 0.056 0.064
3 0.015 0.004 0.038
0.011 0.023 0.007
0.011 0.029 0.011
0.017 0.029 0.001
170 0.052 0.002 0.008
0.047 0.009 0.023
0.054 0.002 0.007
0.048 0.000 0.005
171 0.040 0.008 0.014
0.046 0.008 0.013
0.044 0.001 0.014
0.037 0.001 0.008
59 0.039 0.011 0.011
0.032 0.005 0.004
0.040 0.000 0.005
0.037 0.005 0.011
173 0.030 0.010 0.005
0.037 0.008 0.012
0.041 0.006 0.016
0.037 0.007 0.024
25
Appendix D – Full digital testing results.
Job Scale Factor Rotation Angle
Horizontal Residual (m)
Vertical Residual (m)
∆ Scale
Factor
∆ per 100m
(m) ∆ per 1000m (m)
1 0.999951215 0° 40' 28.0" 0.020 0.332 0.0000487850 0.005 0.049
2 0.999783542 0° 37' 37.0" 0.013 0.015 0.0002164577 0.022 0.216
4 0.999920995 0° 35' 39.0" 0.022 0.010 0.0000790054 0.008 0.079
5 0.999803369 0° 34' 0.0" 0.012 0.007 0.0001966311 0.020 0.197
6 0.999970234 0° 40' 47.0" 0.026 0.117 0.0000297657 0.003 0.030
7 1.000038218 0° 38' 5.0" 0.003 0.034 0.0000382182 0.004 0.038
8 0.999888363 0° 24' 16.0" 0.020 0.029 0.0001116371 0.011 0.112
9 0.999975328 0° 35' 22.0" 0.005 0.000 0.0000246719 0.002 0.025
10 0.9999397 0° 30' 46.0" 0.027 0.030 0.0000603000 0.006 0.060
11 0.999976318 0° 0' 4.0" 0.014 0.011 0.0000236819 0.002 0.024
12 0.999831348 1° 3' 42.0" 0.034 0.037 0.0001686519 0.017 0.169
13 0.99996064 0° 38' 29.0" 0.007 0.019 0.0000393596 0.004 0.039
14 0.99990145 0° 33' 48.0" 0.021 0.014 0.0000985498 0.010 0.099
15 0.99986819 0° 30' 9.0" 0.007 0.009 0.0001318100 0.013 0.132
16 0.999997381 0° 24' 2.0" 0.010 0.008 0.0000026186 0.000 0.003
17 0.999884607 0° 31' 12.0" 0.037 0.039 0.0001153926 0.012 0.115
18 1.000032253 0° 44' 30.0" 0.021 0.001 0.0000322525 0.003 0.032
19 0.999942053 0° 36' 11.0" 0.020 0.020 0.0000579470 0.006 0.058
20 0.999964558 0° 39' 27.0" 0.017 0.014 0.0000354417 0.004 0.035
21 1.000162536 0° 41' 46.0" 0.027 0.082 0.0001625355 0.016 0.163
22 0.999886388 0° 28' 34.0" 0.023 0.000 0.0001136122 0.011 0.114
23 0.99998362 0° 39' 47.0" 0.032 0.050 0.0000163800 0.002 0.016
24 0.999943226 0° 22' 12.0" 0.057 0.010 0.0000567737 0.006 0.057
25 0.999951644 0° 33' 14.0" 0.015 0.123 0.0000483564 0.005 0.048
26 0.999970467 0° 34' 35.0" 0.031 0.034 0.0000295335 0.003 0.030
27 0.999982137 0° 26' 29.0" 0.010 0.011 0.0000178629 0.002 0.018
28 0.999936356 0° 36' 38.0" 0.009 0.012 0.0000636443 0.006 0.064
29 0.999934603 0° 33' 19.0" 0.015 0.019 0.0000653973 0.007 0.065
30 0.99974627 0° 23' 9.0" 0.012 0.020 0.0002537298 0.025 0.254
31 0.999695036 0° 26' 1.0" 0.029 0.025 0.0003049645 0.030 0.305
33 0.999937099 0° 39' 41.0" 0.019 0.017 0.0000629014 0.006 0.063
34 0.999918229 0° 26' 35.0" 0.022 0.020 0.0000817706 0.008 0.082
35 1.000051219 0° 51' 57.0" 0.021 0.005 0.0000512186 0.005 0.051
36 1.000096052 0° 38' 37.0" 0.031 0.040 0.0000960522 0.010 0.096
37 0.999194569 0° 24' 24.0" 0.022 0.045 0.0008054310 0.081 0.805
