Hybrid Fly-by-Wire Quadrotor Controller

Abstract

This article presents one solution to a quadrotor control problem that is based on a discrete automaton. This automaton combines classical PID and more sophisticated LQ controllers to create a hybrid control system. This closed loop control concept is expanded with an open loop controller that enables the aircraft to perform aggressive flying maneuvers. The combination of open and closed loop controllers builds a hybrid controller concept that allows directed and autonomous flying of the quadrotor aerial vehicle. Proposed control concept was tested on an elaborate mathematical model. The article discusses these test results and presents the means to develop such a controller.

U radu je opisan hibridni upravljački koncept bespilotne letjelice pogonjene s četiri rotora, koji objedinjuje klasične PID regulatore i naprednije LQ regulatore primjenom Mooreova automata. Takav je hibridni koncept upravljanja u zatvorenoj petlji nadograđen upravljanjem u otvorenoj petlji koje omogućuje ostvarenje agresivnih letačkih manevara. Osim toga, kombinacija upravljanja u otvorenoj i zatvorenoj petlji omogućuje i daljinsko upravljanje letjelicom zasnovano na vizualnoj povratnoj vezi. Predloženi sustav upravljanja letjelicom testiran je na iscrpnom matematičkom modelu letjelice.

Key words:

• Hybrid control
• Rotorcraft
• Unmanned aerial vehicle

Ključne riječi:

• bespilotna letjelica
• hibridno upravljanje
• rotokopter

Additional information

Notes on contributors

Matko Orsag

Matko Orsag received his B.S.E.E. in 2008 at the University of Zagreb, Croatia. He is currently employed at the Faculty of Electrical Engineering and Computing, University of Zagreb, as a research assistant and a full-time Ph.D. student funded by the Ministry of Science, Education and Sports, Republic of Croatia. His main areas of interest are autonomous systems, robotics and intelligent control systems. During his undergraduate years he received several student awards, as well as a 2008. bronze plaque “Josip Lončar” for overall outstanding academic achievement. He also received the University of Zagreb Rector Award for the best student projects in 2006. He is a coauthor of several papers presented at international conferences and published in proceedings.

Marina Poropat

Marina Poropat works at “Tehnozavod-Marušic, Security & Communication Systems”, as a project manager. She got her degree at the Faculty of Electrical Engineering (2003–2009, course: Automatics) where she wrote her thesis on the theme of “LQR control algorithm on a four-rotor aircraft”. During her student days she was a member of BEST, an international student organization where she developed her soft skills and especially her interest in marketing and design. Her major roles include coordinating different projects, both local and international, as well as being member of the board of the Local BEST Group Zagreb. Born in a bilingual surrounding her mother tongue are both Croatian and Italian, she speaks English fluently, German and Japanese passively.

Stjepan Bogdan

Stjepan Bogdan received his Ph.D.E.E. in 1999, M.S.E.E. in 1993 and B.S.E.E. in 1990 at the University of Zagreb, Croatia. Currently he is an associate professor at the Faculty of Electrical Engineering and Computing, University of Zagreb. His main areas of interest are discrete event systems, intelligent control systems, and autonomous systems. He is a coauthor of three books and numerous papers published in journals and proceedings. He serves as associate editor of IEEE Transactions of Automation Science and Engineering, Journal of Intelligent and Robotic Systems, Transactions of the Institute of Measurement & Control and Journal of Control Theory and Applications.