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The Ministry of Transport recently installed an analytical
stereoplotter and aerial triangulation software through
Italian aid. It is being used to compile mapping of
projected road routes.
The University of Zimbabwe now has an analytical plotter
and an analogue plotter with a semi automatic table.
Aerial triangulation is by the Bundle Adjustment method.
Technicians and students have completed a map of the
University Campus and are hoping in the future to use
terrestrial photogrammetry to help monitor the
deterioration and repair of the ruins at Great Zimbabwe.
Photogrammetry instrumentation, computer hardware
and software, and technical education were received
through a West German Aid agreement.
A commercial air survey company carries out the large
scale development and engineering mapping required by
the country. At present analogue stereoplotters are used
for aerial triangulation and data collection. Orthophoto-
mapping is carried out and the company has its own
aircraft and photolab, to satisfy the aerial photography
requirements of its own mapping and that of other
agencies. The company is hoping to move into the digital
mapping field in the near future.
GEOGRAPHICAL INFORMATION SYSTEMS AND
DIGITAL MAPPING
Geographical Information Systems are a very new area
of technology in Zimbabwe but a start has been made to
nationally co-ordinate activities in GIS.
A National Committee for Land and Geographical
Information Systems (LIS/GIS) was formed in response
to a call in 1989 by a senior member of the Department
of the Surveyor-General. This National Committee
(which reports to an Executive Committee) includes
members from government and local government
departments, technical and academic institutions and
commercial companies, and currently operates under the
aegis of the Surveyor-General.
The aims of the National Committee are primarily
concerned with the co-ordination and methodical
development of LIS/GIS technology in Zimbabwe. At the
first seminar on LIS/GIS entitled “Concepts and Issues
for Zimbabwe Decision Makers” the Chairman of the
Department of Surveying, University of Zimbabwe said
that the survey control network and existing mapping
provided the essential components to embark on a nation
wide land information system. The second LIS/GIS
seminar entitled “Users and Uses” concluded with a
number of recommendations, most of which the
Committee has adopted as a mandate.
Forging close ties with the user/potential user group,
keeping all parties informed of activities through
information — publicity, establishing standards and
encouraging adoption of a common referencing system
and symbology are the main points of the mandate. So
far, in response to the mandate, the Committee has
produced a draft policy document for national LIS/GIS but
the document will be under a process of evolution for
some time to come. The Committee has expressed its
59
intention to become a component of the Research
Council of Zimbabwe with the Committee for Remote
Sensing, but may later seek total autonomy. A newsletter
has been established to fill its information dissemination
role, and a subcommittee has been set up to evolve
standards, geocodes and common boundaries. The
Committee is in touch with a number of organisations,
both locally, regionally and internationally with the
intention of learning and gaining direction from similar
existing facilities. The Committee is currently compiling a
list of users and uses within Zimbabwe and hopes to
receive technical and administrative assistance for a
number of projects, through the World Bank Committee
for Environmental Information Systems.
Digital Mapping is also in early stages of development.
There are three photogrammetrical stereoplotters in the
country that are able to collect information digitally. A
Planicart E3 at the Department of the Surveyor-General
is linked via computer to Resource & Analytical Mapping
Systems (RAMS) software. Large scale mapping is
plotted and simultaneously stored in map files which are
then edited at interactive workstations. The map can
then be automatically scribed on a flat bed plotter.
Automatic scribing is, however, very limited due to the
poor selection of scribing points.
A large proportion of all the cadastral information of the
country has been entered into map files. Each file covers
1/32 of a degree square. All of the control network
including trigonometrical stations, town survey marks and
other bench marks, together with the attribute
information, are stored in vector computer files.
The Zeiss analytical plotter at the Ministry of Transport,
used for large scale mapping along proposed road sites,
collects digital topographic detail in the autocad files
which are then passed to the engineering section to
calculate (engineering) solutions for road construction.
The maps are output on a drum plotter.
Some large scale digital maps have been compiled on
the Department of Surveying's Zeiss analytical plotter.
Most of these have been done as exercises by students.
Soon the Department will provide some digital map sets
to the Institute of Mining Research as part of a joint
project.
A number of other Government Departments have
already invested in small systems which facilitate the
digitising of existing maps for the addition of other data
sets. The primary function of these systems is to develop
information systems.
DEVELOPMENTS AND ACTIVITIES IN REMOTE
SENSING
The establishment of the National Remote Sensing
Facility (NRSF) in Zimbabwe is a joint Technical
Co-operation project between the government of the
Republic of Zimbabwe and the Federal Republic of
Germany. Phase 1 of the project started in April 1988.
The NRSF is now in its second phase. Duration of
German support for the project is about eight years.
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