6B-4-2
and meteorological data.
The moving observation is to identify the mentioned four kinds
of informations by the vehicle mounted equipment. And it is
fundamental data for spatial extension of mentioned fixed-point
observation.
2. DEVELOPMENT OF SPATIAL DATA ACQUISITION
TOOL
2.1 Functions of Developed System
The basic functions of developed spatial data acquisition tool
are classified to main three parts:
1) Data Acquisition
View imageries are observed and recorded by CCD or Video
Camera. And GPS and 3D sensor instruments that mounted
on platform measure its spatial location and sensor (camera)
condition. All of data can be refereed with the same GPS time.
2) Data Collection/Calibration
All of collected data is transferred to the computer and each of
them integrated in the same time dimension. About recorded
imageries, some of interested area stereo pair imageries are
selected and captured from the video recorder according to the
every collected time. Finally all of interested area imageries
are accumulated with location and camera condition data as an
analysis.
3) Mapping
3-Dimensional measurement is performed by referring
accumulated other condition data. Resulting to the spatial data
acquisition, map is generated with the scale range from
1:25,000 to 1:50,000.
2.2 System Configuration
Our developed tool or system configuration is illustrated as in
Figure.1.
CCD Camera
(Field Work)
Video/Computer
Interface
3D Sensor
(Lab. Work)
RS232C
i Range Finder
i (FieldWork)
Fig. 1 System Configuration
Both left and right sides of this figure are image and reference
data recording parts at fieldwork. Mainly CCD camera is used for
observation and normal video camera is for recording and
monitoring. Continuous field view image is collected and
recorded to video recorder automatically. The platform that we
suppose, is crane at the fixed-point observation and land-based
vehicle at moving observation respectively. GPS receiver is used
for camera positioning
The middle of its is data analysis part at lab. work. At the first
step, recorded continuous image is re-played for searching
interested point by our human eyes and captured and digitized as
the digital stereo pair images with 1,500 width X 1125 depth,
RGB by video/computer interface. Here is to generate the 3D
data (mentioned four kinds of informations) from the digitized
stereo imageries and orientation parameters that obtained by
platform mounted equipment.
2.2 Orientation Parameters
Our developed system supposes following conditions;
1) Exterior orientation parameters
Camera Position (Xo, Yo, Zo) is provided by GPS receiver.
Camera Condition (co, , k ) by 3D sensor.
3) Inner Orientation parameters
All of them are estimated by mentioned later Lab. level
experiment.
2.3 Lab. Level Experiment for System Evaluation and 3D
Accuracy Verification
In order to confirm on the camera capabilities and to estimate
inner orientation parameters, Lab. level experiment was carried
out.
Figure.2 is the photo of its experiment.
Fig.2 Lab. Level Experiment
1 ) Experiment
Target for 3D Measurement
The configurations of actual Lab. level experiment and axis
definition are shown in Figure 3. White circle points are used for
control of camera calibration and black circle points are the
verification of accuracy respectively. The camera with 3D sensor
can move on dotted line. So that base line can be controlled by
manual operation.