Robust control of unmanned aerial vehicle with four rotors

Mikro zračna vozila danas predstavljaju jednu od najaktivnijih grana mobilne robotike. Napredak tehnologije omogućio je razvoj agilnih i kompaktnih letjelica sa sve širom primjenom u industriji i svakodnevnom životu. Sve složenije primjene zahtijevaju određeni stupanj autonomnog djelovanja za što je nužno osigurati pouzdanu primjenu etjelica u složenim realnim okolinama. Jedan od koraka je i razvoj i implementacija naprednijih robusnih algoritama koji će omogućiti kretanje letjelica u realnim uvjetima uz prisutne nepoznate poremećaje. Ovaj rad bavi se izradom i primjenom quadrotor helikoptera u evaluaciji obrađenih upravljačkih zakona. U sklopu rada obrađena je kinematika i dinamika krutog tijela sa šest stupnjeva slobode koje predstavlja quadrotor. Izveden je puni matematički model sustava koji je zatim lineariziran korištenjem razumnih pretpostavki. Na temelju ineariziranog modela provedena je sinteza upravljačkih zakona za linearni PID regulator te robusne regulatore s kliznim režimom rada prvog i drugog reda. Izrađena je računalna simulacija pomoću koje su ispitane i uspoređene performanse pojedinih upravljačkih zakona za slučajeve sa i bez prisutnih vanjskih poremećaja. Praktični dio rada sastoji se od odabira komponenti za izradu fizičkog modela quadrotor helikoptera te njegovog sastavljanja i testiranja. Sa izrađenim modelom moguće je upravljati daljinski no moguće mu je i zadavati samostalne misije pomoću softvera za autonoman let.Micro air vehicles are regarded as one of the most active areas of research in the field of mobile robotics. Rapid advances of technologies has enabled development of very agile and compact air vehicles with wide range of applications both in industry and everyday life. Increasing number of sophisticated applications require certain degree of autonomy of the air vehicles, for which certain safety standards have to be achieved first. One of the imperatives is development and implementation of more advanced robust control algorithms which will enable air vehicles to safetly perform useful tasks in unknown environment. Main topic of this master’s thesis is the application of quadrotor helicopter platform in evaluation of described robust control laws. Kinematics and dynamics of six degrees of freedom rigid bodies, which include quadrotors, was studied in detail. A full dynamical model of quadrotor was derived and linearized using reasonable assumptions. Linearized model was then used to design control laws for linear PID controller and robust sliding mode controllers of first and second order. Computer simulation was made and used for numerical evaluation and performance comparison of derived control laws in cases both with and without external disturbances. Practical part of thesis consists of components selection, building and testing of a functioning quadrotor helicopter. This quadrotor can be flown via remote control but is also capable of executing autonomous missions recieved from mission planer software for autonomous vehicles