Jeyapalan, Kandiah
AS BUILT SURVEYS OF ROAD SIDE FEATURES FOR GIS, VISUALIZATION, AND VIRTUAL REALITY
K.Jeyapalan!, D.Bhagawati”
"Professor of Civil Engineering
428 Town Engineering Hall
kjp@iastate.edu
"Graduate Research Assistant
GIS Support and Research Facility
218 Durham Hall
dwipen@iastate.edu
Iowa State University
Ames, IA 50011
KEY WORDS: GIS, Soft Photogrammetry, Videologging, Virtual Reality, 3D View
ABSTRACT
The paper describes Total Station, Differential Global Positioning System (DGPS), Videologging softphotogrammetric
and virtual reality methods of collecting data on road side features of urban, city and rural roads for creating a
Geographic Information System (GIS). Total station can be used in mapping at a scale of 1"— 25ft or less; DGPS at 1"—
50 ft or less and Video images with softphotogrammetry at 1"— 25 ft or less. Data collecting using Total Station and
DGPS are time consuming in the field where as soft photogrammetry uses more office time. Virtual Reality can be used
for 3D visualization, fly through, and 3D view of proposed modifications.
INTRODUCTION
Recent advances in GPS, Total Station and Soft photogrammetry enable surveyors and photogrammetrists to undertake
"As Built Surveys" of road side features at a cost that is affordable within the maintenance budget of state, city and
county agencies. Typically, a preliminary survey for road development and construction cost between $15,000 to
$20,000 per mile. An “As Built” survey is attractive if the cost is less than $ 1,000/mile. A mapping accuracy 1” = 100’
is sufficient in a rural area where as a mapping accuracy of 1” = 50’ and I” = 25’ may be required in urban and
metropolitan areas, respectively. The most accurate method of doing an “As Built” survey is by Total Station, but it is
more costly and time consuming than GPS, videologging and soft photogrammetry.
Videologging, using digital cameras, GPS, Inertial Navigation System (INS) and tilt sensors, are currently used for
inventory and visual verification of roadside features. Soft photogrammetry has developed to an extent that it is now
available, at an affordable cost, for a PC and Unix workstation. Videologging images and soft photogrammetry can be
used to do “As Built” surveys wherever DGPS cannot be used and Total Station are cost prohibitive.
The objectives of this paper are to present the results of the “As Built” surveys done in Oregon and Washington by
Olympia and Thurston county in cooperation with Iowa State University (ISU) and Mandli Corporation using Total
Sation, DGPS and videologging.
The paper describes the procedure and gives results of:
* aGIS for roadside features in rural, urban and metropolitan area by Total Station and DGPS
* inventory survey by videologging
® an “As built” survey by Soft photogrammetry,
® virtual reality
Conclusion and recommendation follow.
406 International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part B5. Amsterdam 2000.
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