A photogrammetric flight was performed in December 2016 as BVLOS (Beyond Visual Line of Sight) operation over Penguin Island (South Shetland Islands, Western Antarctica). Images were taken by the PW-ZOOM fixed-wing UAV equipped with a digital SLR Canon 700D camera. The flight was performed at 550 m ASL and covered a total distance of 231.58 km.The plane take-off and landing site was near the H. Arctowski Polish Antarctic Station (Arctowski) on King George Island, South Shetlands. The main aim of the mission was to collect environmental data to estimate the size of penguin and pinniped breeding populations and to map vegetation cover and landforms. The plane returned to Arctowski with 1630 images of Penguin Island with the ground sample distance (GSD) lower than 0.07 m. The images allowed us to locate and identify individuals of two penguin species (Adélie and chinstrap), and individuals of two species of pinnipeds (Southern elephant seal and Weddell seal). Three types of tundra communities were mapped together with numerous landforms such as: volcanic, mass movement, fluvial, coastal and aeolian ones. The UAV BVLOS photogrammetric operation proved to be very robust in gathering valuable qualitative and quantitative data necessary for monitoring distant and isolated polar environments.
An unmanned aerial vehicle (UAV) as an alternative to manned aircrafts is an excellent, less invasive, safe tool, especially in sensitive polar regions. Here we used a fixed-wing UAV to collect data on seabird and pinniped populations in hardly accessible Antarctic areas. The implementation of an auto-piloted UAV equipped with a digital camera (Canon EOS 700D, 35 mm f/2.0 lens) allowed us to collect high-quality material applicable to a quantitative analysis of the fauna populations. A successful photogrammetric mission, at an altitude of 550 m above sea level, was accomplished during one Beyond Visual Line of Sight flight above hard-to-access Penguin Island and Turret Point Oasis (King George Island). Obtained selected RGB images were processed to generate a panoramic image stitch with resolution of 0.07 m ground sampling distance. A total of 4290 (SD = 33.08) breeding individuals of two penguin species, Adélie (Pygoscelis adeliae) and chinstrap (Pygoscelis antarcticus), 426 (SD = 7.78) individuals of the southern elephant seal (Mirounga leonina) and 6 individuals of the Weddell seal (Leptonychotes weddellii) were identified in both study areas. Additionally, 222 (SD = 2.0) individuals of the southern giant petrel (Macronectes giganteus) and 76 (SD = 1.0) of the Antarctic shag (Phalacrocorax atriceps bransfieldensis) in the Turret Point area were recognized. The presented observations on the natural history of the investigated fauna together with the available literature may be useful in future research on population trends. A comparison with available historical data for both investigated areas suggests a decrease of 68.29% in both penguin species in the 1980-2016 period. The presented results confirmed that UAVs are useful for remote census work for Antarctic seabirds.
PurposeThe purpose of this paper is to present a study on methods for load spectrum (LS) determination and extrapolation, basing on data obtained from experiments.Design/methodology/approachA sequence of loads registered in flight becomes an object of analysis aimed to calculate full cycles of loads, and on this basis two possible types of LS are determined, i.e. as the transfer array, or in classic form (as the plot presenting appearances of load increments, called “incremental load spectrum”). While the use of incremental LS enables just application of deterministic extrapolation methods, the transfer array enables application of the stochastic method of extrapolation that consists of random redistribution of the transfer array cell values.FindingsThe paper presents a comparison between the results of application of deterministic or stochastic extrapolation methods. Attention was focused on the LS registered during thermal flights. The stochastic extrapolation method is less conservative than the deterministic ones, and enables better adjustment of estimated LS to the reality.Originality/valueThe novel extrapolation method consists of cumulation of the results of stochastic redistribution of the values in transfer array obtained from the experiment.
The aim of this article is to show geomorphological mapping of remote Antarctic locations using images taken by a fixed-wing unmanned aerial vehicle (UAV) during the Beyond Visual Line of Sight (BVLOS) operations. We mapped landform assemblages developed in forelands of Ecology Glacier (EGF), Sphinx Glacier (SGF) and Baranowski Glacier (BGF) in Antarctic Specially Protected Area No. 128 (ASPA 128) on King George Island (South Shetland Islands) and inferred about glacial dynamics. The orthophoto and digital elevation model allowed for geomorphological mapping of glacial forelands, including (i) glacial depositional landforms, (ii) fluvial and fluvioglacial landforms, (iii) littoral and lacustrine landforms, (iv) bodies of water, and (v) other. The largest area is occupied by ground moraine and glacial lagoons on EGF and BGF. The most profound features of EGF are the large latero-frontal moraine ridges from Little Ice Age and the first half of the 20th century. Large areas of ground moraine, frequently fluted and marked with large recessional moraine ridges, dominate on SGF. A significant percentage of bedrock outcrops and end moraine complexes characterize BGF. The landform assemblages are typical for discontinuous fast ice flow of tidewater glaciers over a deformable bed. It is inferred that ice flow velocity decreased as a result of recession from the sea coast, resulting in a significant decrease in the length of ice cliffs and decrease in calving rate. Image acquisition during the fixed-wing UAV BVLOS operation proved to be a very robust technique in harsh polar conditions of King George Island.
ABSTRACT:A program to monitor bird and pinniped species in the vicinity of Arctowski Station, King George Island, South Shetlands, Antarctica, has been conducted over the past 38 years. Annual monitoring of these indicator species includes estimations of breeding population sizes of three Pygoscelis penguin species: Adélie, gentoo and chinstrap. Six penguin colonies situated on the western shores of two bays: Admiralty and King George are investigated. To study changes in penguin populations Unmanned Aerial Vehicles were used for the first time in the 2014/15 austral summer season. During photogrammetric flights the high-resolution images of eight penguin breeding colonies were taken. Obtained high resolution images were used for estimation of breeding population size and compared with the results of measurements taken at the same time from the ground. During this Antarctic expedition eight successful photogrammetry missions (total distance 1500 km) were performed. Images were taken with digital SLR Canon 700D, Nikon D5300, Nikon D5100 with a 35mm objective lens. Flights altitude at 350 -400 AGL, allowed images to be taken with a resolution GSD (ground sample distance) less than 5 cm. The Image J software analysis method was tested to provide automatic population estimates from obtained images. The use of UAV for monitoring of indicator species, enabled data acquisition from areas inaccessible by ground methods.
The history of UAVs is relatively long and many such vehicles are in service for different tasks. They can be used even in environments inhospitable for humans, e.g. because of extreme temperature. Moreover, they can perform a task that is difficult or impossible for a manned aircraft because of its size and usually relatively high airspeed. The photogrammetric tasks belong to this group, especially if we need to take high-resolution pictures during low level flight. The advantages of a small UAV for such mission are more evident if we want to investigate the natural environment, where the wild animals are. The paper presents the small UAV designed for a special task, which is counting of the penguins in Antarctica. Inhabited area, extreme weather conditions, the fearfulness of penguins and the goal of the mission put up certain requirements for the UAV. It had to be a reliable, stable platform, which is able to carry photogrammetric equipment and to perform precise flight to cover all investigated areas. The presented UAV was used on such missions in Antarctica in 2014 and 2015. All mentioned tasks were successfully accomplished.
Recent developments in unmanned aerial vehicles (UAVs) have resulted in high-resolution digital elevation models (DEMs) of vulnerable coastal environments, including beach–foredune topography. If performed repetitively, they can offer an excellent tool to determine the spatial and temporal changes in the sediment budget, which may be required for proper land management. However, the quality of a UAV, slope parameters, and vegetation significantly influence DEM accuracy. The aim of this study is to compare precise GPS-RTK transects across a section of the South Baltic coast in Poland with those obtained from a DEM based on high-resolution and high-accuracy images obtained by a wind-resistant, high-quality fixed-wing UAV during beyond visual line of sight operation (BVLOS). Different land cover classes, slope inclination, and general curvature, as well as surface roughness, were taken into consideration as possible factors influencing the uncertainty. The study revealed that marram grass greatly affects the accuracy of the UAV-derived model and that the uncertainty of the UAV-derived DEM increases together with increasing slope inclination and, to a lesser degree, with increasing general slope curvature. We showed that sediment budget determinations with the use of a UAV-based DEM are correct only where grass cover is sparse, in our study, up to 20% of the area.
The tailless fixed-wing aircraft have a very compact design and therefore are very attractive as portable unmanned aerial vehicle (UAV) platforms. There is a special need for using such platforms in case of operations in such backlands as Antarctica, because very often the equipment necessary for preparing improvised airfields near Antarctic scientific bases and organizing the UAV flights must be hand-carried. The main aim of this paper is to present the design activity and testing of a number of UAV configurations to be used for aerial monitoring in Antarctic areas and collecting data of local ecosystems. Two UAV flying-wing platforms-MONICA-1 and MONICA-2-were developed, differing largely with respect to wing-loading and weight-to-power ratios. The lightweight Skywalker X-8 built from the kit and used as a baseline configuration was adapted for special photogrammetric missions. It was found that the main advantage of such light UAV consists in a very simple takeoff system (i.e. bungee), however due to low wing loading a usage of this UAV is limited to the so-called 'weather windows' of relatively low wind, which do not frequently occur in Antarctica. MONICA-1 is much less sensitive to gust but as a heavy platform it is more difficult to handle in harsh Antarctic environment. To be able to operate in much wider range of the wind, vertical gust and heavy turbulence, typical for Antarctic zones, a special UAV platform-called MONICA-2-was designed and manufactured. MONICA-2 platform of higher wing loading is smaller than the X-8 and at the same time is able to carry the same photogrammetry equipment. The effort of designers focused on achieving low sensitivity to gust and turbulence by increasing the critical angle of attack and natural static and dynamic stability in the whole range of operational speeds. The paper contains the selected design details and some observations from the flight tests.
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