Design of a Path Tracking Controller for Unmanned Aerial Vehicle in Global Vision System

Bespilotne letjelice imaju sve veću upotrebu i važnost u svakodnevnom životu. Kroz povijest se mijenjala njihova upotreba pa postoji nekoliko vrsta. Sve većom upotrebom u poljoprivredi, geodeziji te za zabavu javila se potreba za zakonskom regulativom. Najveći izazov kod bespilotnih letjelica je njihovo upravljanje i točno pozicioniranje. Za rješavanje tog problema potrebno je dobro odrediti matematički model za sintezu sustava upravljanja. Model heksakopera je izveden korištenjem Newtonovih zakona. Korištenjem kvaterniona, u odnosu na Eulerove kutove, smanjuje se nestabilnost te ubrzava numerički izračun. Projektirani regulator za slijeđenje željene trajektorije ima raspoložive informacije o trenutnoj poziciji i orijentaciji letjelice. Glavno svojstvo letjelica je njihova nestabilnost. Kako bi se upravljalo preko računala, modificirani je kontroler heksakoptera tako da Arduino, uz dodatne elemente za filtriranje signala, generira upravljački signal. Algoritam upravljanja implementiran je u robotski operativnom sustavu - ROSu. Na kraju su prikazani rezultati algoritma.The use and importance of Unmanned Aerial Vehicles are increasing in everyday life. Throughout history, their use has been changed and there are several types. Legal regulations had to be published because of their increasing use in agriculture, geodesy and for entertainment. The biggest challenge for unmanned aerial vehicles is control and accurate positioning. To solve this problem, it is necessary to define a mathematical model for the synthesis of the control system. The model of flying hexacopter is derived using classical Newton laws. By using quaternions, relative to the Euler angles, instability decreases and the numerical calculations accelerate. The designed controller for the trajectory tracking has available information on the current position and orientation of the aircraft. The main property of such devices is their instability. In order to control the hexacopter from the computer, the hexachopter controller is modified so that an Arduino, with some additional elements for filtering signals, can generate a control signal. Algorithm for control is implemented in the robotic operating system - ROS. Results of the control algorithm are presented in the end of the paper