UAVs open up a whole new world

UAVs open up a whole new world

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South America’s smallest country has started leveraging the many benefits of UAV technology in areas where traditional remote sensing or survey techniques fall short owing to its deep forest cover

Unmanned aerial vehicles (UAVs), used for military applications for long, have now entered the civil market, opening up new possibilities within the mapping and remote sensing industry. With the ability to acquire highly accurate imagery from a low altitude, UAVs have proved to be helpful in the acquisition of remote sensing data in locations that are difficult to access or in regions where dense cloud coverage throughout the year makes it impossible for satellites to collect good-quality images.

Located in South America on the north of Brazil, Suriname is the smallest country in the region at just under 165,000 square km. With a number of national parks, including a UNESCO World Heritage Site — the Central Suriname Nature Reserve — in the upper Coppename River watershed, the country is famous for its unspoiled forest biodiversity. However, with 90% of it covered by tropical rain forests, Suriname is very hard to map using traditional remote sensing techniques. The introduction of the UAVs in 2012 formed a revolutionary breakthrough in the mapping business in Suriname with several applications being initiated in land management and mining in the past six months.

Mapping
Closely related to the application of UAVs to support traditional authorities in preserving their community boundaries, this technology finds its use in mapping households and facilities of traditional villages.

Suriname, with a population of around 0.5 million is made up of several distinct ethnic groups. To preserve the privacy and cultural integrity of such a diversity, data inventory by UAVs can take place without teams being actively and visibly present in the localities, thus avoiding social and cultural conflicts. Performing a settlement inventory and mapping the terrain in 3D provides the necessary data, e.g. to design water distribution networks or electrification projects. A first pilot project is currently being planned.

Mining
Suriname’s economy is dominated by the baux ite industry, which accounts for more than 15% of the GDP and 70% of export earnings. It has also recently started exploiting some of its sizeable oil and gold reserves.

Likewise, the most common use of UAV technology in Suriname is within the bauxite mine industry where weekly missions provide data to evaluate mine progression. By using low-altitude flights (100-150 metre above surface) images are acquired with an overlap of 75-80%. Following a six-hour post processing, both digital elevation models and ortho photos are available that provide up-to-date information regarding surface changes, calculating the amount of ore that is removed from the pit and transported to the different stockpiles.

Apart from providing an accurate tool to verify the transportation costs as billed by the contractor, mining companies now have weekly, accurate surveys to support their planning activities, something that could not have been possible in the same timeframe using traditional survey. When benchmarking the use of UAVs against traditional survey, a mining company calculated a cost ratio of 1: 187, a solid business case to invest in UAV technology to support planning and operations .

Border disputes
Mining and forestry are the two major growing industries currently present in the interiors of Suriname on both, a large industrial scale as well as a small individual scale. Delineation of concession boundaries is therefore a very crucial aspect in regulating the activities but nevertheless rather difficult due to the dense canopy cover. Inaccessibility of suitable take-off and landing spots, however, pose a challenge to the use of UAVs in the small mining industry.

Traditional communities that live in the interior of Suriname, rely on the forest and savannah to provide food, building materials and natural resources for their village. The presence of illegal operations along the community boundaries, often initiate disputes between the traditional communities and the operating companies or individuals. Obtaining legal proof of illegal border crossing activities is a necessity in such a situation, although often a difficult case to build.

This opens possibilities for the UAV business. Within the village boundaries, suitable take-off and landing locations can easily be found and maintained and permanent ground control points can be constructed. In Suriname, GISsat closed an agreement with a local community to provide baseline inventory data on a regular basis. The imagery is acquired from an altitude of 300 metre, thus covering a large area within one flight. The purpose of the operation is to monitor activities along the official community boundaries in order to provide legal proof for the local community when illegal mining or forestry activities take place. Although still executed on a small scale, the authorities are striving to get this supported by an international forum and to assist in setting up a national monitoring programme to support local authorities.

Project management
Baseline inventory and periodic monitoring form the t wo key aspects that define the application of UAV technology. Within the public works industry, UAVs were used to monitor as-built construction activities of a large social housing project. By comparing the imagery with the design plans, non-conformities could be identified during the construction phase and proper management decisions could be made before the construction reached its final stage. For the executing contractor, the imagery was used as a reference for progress overview.

Although still relatively new in Suriname, UAVs open up vast possibilities for land management, spatial monitoring and terrain visualisation, areas where traditional remote sensing or survey techniques fall short. Fast deployment, quick and highly accurate results and no impact by clouds are the key aspects that make this technology a winner for tropical environments.