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[Studies in Computational Intelligence 481] Artur Babiarz, Robert Bieda, Karol Jędrasiak, Aleksander Nawrat (auth.), Aleksander Nawrat, Zygmunt Kuś (eds.) - Vision Based Systemsfor UAV Applications (2013, Sprin

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344 Conclusions<br />

Control algorithms are another important issues <strong>in</strong> development of <strong>UAV</strong>. There<br />

are three ma<strong>in</strong> applications of vision based algorithms <strong>in</strong> this area. <strong>UAV</strong> objects<br />

can be controlled by send<strong>in</strong>g commands by human terrestrial operator us<strong>in</strong>g gestures.<br />

Systems recogniz<strong>in</strong>g gestures might significantly improve the quality of<br />

control. The other approach is to use aerial vision <strong>in</strong>formation. However, the biggest<br />

challenges here are stabilization and denois<strong>in</strong>g of the video stream, calibration,<br />

<strong>in</strong> order to perform distortion compensation, and improvement of <strong>in</strong>tensity of<br />

illum<strong>in</strong>ation or acquisition noise, for example due to high temperature of the device<br />

surround<strong>in</strong>gs. The third application of vision based control algorithms is navigation<br />

of <strong>UAV</strong>s <strong>in</strong> an unknown dynamically chang<strong>in</strong>g environment. Geodesic<br />

terra<strong>in</strong> maps are commonly used <strong>in</strong> this area. However, there are a lot of disadvantages<br />

related with this approach. Such maps are often outdated and they are not<br />

<strong>in</strong>clude <strong>in</strong>formation about some tall build<strong>in</strong>gs or flora. The big problem here is<br />

also connected with the appearance of other fly<strong>in</strong>g units <strong>in</strong> a local environment of<br />

<strong>UAV</strong>s. Control of the drones and plann<strong>in</strong>g a mission us<strong>in</strong>g 3D maps is an important<br />

issue and big challeng<strong>in</strong>g problem. Therefore, it should be solved <strong>in</strong> order<br />

to simplify and precise the process of navigation <strong>in</strong> a dynamically chang<strong>in</strong>g<br />

environments.<br />

An important task dur<strong>in</strong>g design<strong>in</strong>g and construction of <strong>UAV</strong>s is process of<br />

test<strong>in</strong>g: simulations and real life experiments. The first step of test<strong>in</strong>g is utilization<br />

of data us<strong>in</strong>g advanced simulation environments. The <strong>UAV</strong> navigation algorithms<br />

can be implemented and followed by established trajectory. At the same time, it is<br />

possible to observe video streams acquired from virtual cameras, which are placed<br />

under <strong>UAV</strong> object. The video stream from a camera should be wirelessly transmit<br />

to human operator us<strong>in</strong>g ground base station, and should be encrypted due to the<br />

high risk of wireless data capture. Thus, a significant network bandwidth and dedicated<br />

image and sound compression algorithms are required.<br />

The aim of simulation tests and real life experiments are to obta<strong>in</strong> positive results<br />

us<strong>in</strong>g simulations. Such results are considered as a first stage of development<br />

and improvement of classification and detection algorithms. Multiple sources of<br />

<strong>in</strong>formation are used to improve the quality of recognition. But the other problem<br />

is aris<strong>in</strong>g here. The <strong>in</strong>creased amount of <strong>in</strong>formation sometimes can results <strong>in</strong><br />

deterioration of real time process<strong>in</strong>g. Therefore, dimensional reduction and cluster<strong>in</strong>g<br />

algorithms should be used to reduce the amount of data.<br />

The area of <strong>UAV</strong> development is broad and essentially new. Therefore, the algorithms<br />

and methods used <strong>in</strong> this field should be improved and <strong>in</strong>creased. All of<br />

the presented solutions are supported by analysis of applied techniques, analysis of<br />

new methods and results, and <strong>in</strong>spir<strong>in</strong>g discussions. The new methods applied <strong>in</strong><br />

this area show promis<strong>in</strong>g future, however, still there are a lot of challeng<strong>in</strong>g tasks<br />

for scientists and developers, which should be discussed and solved.

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