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Aerial Photography
40693 linekilometres had to be flown to cover the area to be
mapped with scale 1:30.000 and 1: 50.000 aerial photographs.
Photogrammetry Compilation
9378 stereo models had to be compiled. All geographic
information digitized was to be registered in 3D. Nine different
landuse classes had to be registered.
Field Compilation
1662 map sheets had to be verified in the field Geographic
names should be collected and approved. Administrative
boundaries down to “Desa” level should be included in the
maps. Roads had to be classified into six different classes and
symbols had to be collected for government offices, hospitals,
school etc.
Database Establishment
This is an minor activity in the analog map production, but for
digital geographic information it is a very significant task. For
all the information collected into the database each feature have
to have an unique code with reference to the quality and the data
collection method used.
Cartographic Processing
The map sheet design, the text and symbols had to be digitally
produced. A challenge was to produced a Cartographic product
that was similar to the scale 1:25.000 BAKOSURTANAL
specification for analog produced maps.
Offset Printing
The 1662 digitally produced maps had to be colour separated
into six colour and films for platemaking printed out utilizing an
image setter.
3. PROJECT IMPLEMENTATION
Implementation
Blom ASA of Norway chose a conservative technical approach
in implementation of this big mapping project.
With a limited time frame and with limited financial recourses,
only well tested equipment and software were chosen for the
project. In the project there were some money for maintenance
and training, but little for new investments.
For a project running over eight years it is very different to
predict what shall happen in the technical development in an
industry based on computer technology. If investments in new
equipment should be made, it had to be proven that this resulted
in a productivity gain.
At the time of the project start-up, it were the colour plotters to
be used that caused the biggest concern. At the time they were
very expensive and needed a lot of service.
All production had to take place in Indonesia and for most
Norwegian this is an unfamiliar work environment, with high
temperature and high humidity.
Hiring of personnel started in May 1993 and the first shipment
of equipment arrived in Indonesia July 1993.
4. TECHNOLOGY TRANSFERE
When the first expatriate experts arrived in Indonesia in June-
July 1993 they started their lessons in Bahasa Indonesia at the
same time as they worked on manuals for work procedures.
Ground Control Surveying
Trimble 4000SSE GPS receives, Sokkia Totalstations and Tirta
Harapan Pressure loggers were to be used. The pressure loggers
were used for establishing height control for the islands east of
Lombok. About 8000 kms of trigonometric leveling was
performed using the Sokkia Total stations.
Prior to the start up of the on going mapping project, the
Surveyors from the Indonesian partner, PT. NARCON had no
experience within the field of GPS technology. However they
had a lot of valuable experience from traditional field surveying,
also from remote areas.
Before the start up of the field operations, a course was given
comprising of GPS theory, demands for establishing the GPS
points and how to make an efficient schedule for GPS
observations. Based on this knowledge, the surveying teams
were sent to the field to start the establishing of monuments and
premark for aerial photography. Parallel to this work, the
Supervisors, one for each of the fire field teams, were given
additional training.
The placing of the first order ground control points were mainly
determine by the flight plan. During the flight mission
Kinematic GPS was utilized, this reduced the number of ground
control points needed by about 90% compared with methods for
aerial triangulation previously used. On the request from
BAKOSURTANAL one first order control point was
established close to the capital of each Kabupaten.
It was important to have the monuments and premarking in
place prior to the start up of aerial photography. Later the GPS
observations were made and finally the tidal measurements and
the leveling for height control were performed. Before departure
for field work about one week of training were given to the
surveyors in each of the different activities. All the Surveyors
had a lot of on the job training. The biggest challenge during the
ground control surveying was the communication between the
surveying teams and the transportation in remote areas with
very limited infrastructure.
The whole ground control operation was completed within the
two first years of the project.
Aerial Photography
The aerial photography for the project was sub-control to the
Indonesian company PT.EXSA. Blom-Narcon Cooperation
asked the sub-contracted to complete the aerial photography for
limited geographic areas (photo blocks) at one time before
moving into another area. PT.EXSA however explained that due
to the climatic conditions in Indonesia, it was not possible to
complete the aerial photography for such a big geographic area
within a limited timeframe. Blom-Narcon Cooperation had to
accept this fact and workc together with PT.EXSA to establish
good routines for utilizing kinematics GPS during flight
missions to get an accurate positions for each photo center.
As this in August 1993 was new technology, one expert from
the Agriculture University of Norway, Department of Surveying
was invited to take part in developing this new technology in
Indonesia. The university was asked to support the project in the
initial phase to develop quality control system for GPS
calculations of the projection centers. Monitoring of the quality
and approval of the negative films was a major task for about
12000 aerial photographs. A quality and photo coverage
monitoring system was developed using AutoCAD software.
The position of photocentres were plotted relative to the flight
plan and the quality criteria for both negative film and GPS
were monitored together with the photo coverage. Photo
laboratory personnel and draftsmen with experience from PT.
NARCON were trained to run this monitoring system for photo
coverage.