System Identification and Heuristic Control of Segmented Ailerons for Enhanced Stability of Fixed Wing UAVs


Keywords: Fixed-wing UAV, PID Control, Segmented Control Surfaces, System Identification


Different from conventional aircraft, an investigation on system identification and control design has been carried out on a small
fixed wing unmanned aerial vehicle (UAV) with a multi-segment ailerons. The multi-segment aileron setup is configured as a multi-input
and single-output system and each segment is modeled as a control input. Experiments are conducted in a wind tunnel to determine the
frequency responses of the system and the corresponding transfer functions. Multiple PID controllers are designed and implemented in a
cascaded form for each control surface. Furthermore, a heuristic switching control strategy is implemented for the aircraft where the
multi-segment ailerons perform as a single-segment aileron in a normal flight condition, and adapts to multi-segment control when
encountering severe turbulence or a large angle reference change. Experimental results reveal that although each control surface has
the capability for stabilization of the aircraft, the proposed control strategy by combining the multiple actuation surfaces reduces
the mean squared errors for the roll angle up to $37$ percent in the highly turbulent environment providing superior disturbance
rejection properties to the aircraft.

Author Biographies

Liuping Wang, RMIT University

Liuping Wang received the Ph.D. degree from The University of Sheffield, Sheffield, U.K. She was with the University of Toronto, Toronto, ON, Canada, for eight years in the field of process control. From 1998 to 2002, she was with The University of Newcastle, Callaghan, NSW, Australia. In 2002, she joined RMIT University, Melbourne, VIC, Australia, where she is currently a Professor of Control Engineering. She has authored or co-authored over 190 scientific papers in systems and control. She co-authored a book with Prof. Cluett "From Process Data to Process Control: Ideas for Process Identification and PID Control" (Taylor and Francis, 2000). She co-edited two books with Prof. Garnier "Continuous Time Model Identification From Sampled Data" (Springer-Verlag, 2008) and "System Identification, Environmental Modelling and Control" (Springer Verlag, 2011). She authored the book "Model Predictive Control Design and Implementation Using MATLAB" (Springer Verlag, 2009). She is the Lead Author of the book "PID and Predictive Control of Electrical Drives and Power Converters Using MATLAB" (Wiley-IEEE, 2015). She is the author of the recent book "PID control system design and automatic tuning using MATLAB/Simulink" (Wiley-IEEE Press, 2020).

Abdulghani Mohamed, RMIT University

Abdulghani Mohamed received the Ph.D. degree in aerospace engineering from RMIT University, Melbourne, VIC, Australia. He has successfully made some noteworthy contributions to aeronautical engineering. He has developed the world's most stable Micro Air Vehicle through inventing and patenting a novel biomimetic sensor inspired by birds. His research has significant impact with respect to enabling safer and more efficient flight of aircraft in turbulent weather. He is a multidisciplinary Researcher involved in a number of areas, such as robotics, aerodynamics,turbulence, biomimetics, sensors, dynamics, and control. His current research interests include numerous media outlets, such as scientific magazine articles, interviews on radio and TV, and videos that have attracted a significant view count on social media websites. Dr. Mohamed received a number of awards, including the prestigious 2015 Young Innovators Award.

Alex Fisher, RMIT University

Alex Fisher received the Ph.D. degree in aerospace engineering from RMIT University, Melbourne, VIC, Australia He has been working with RMIT university for last 10 years. He has conducted extensive research into the feasibility of autonomously soaring unmanned aircraft using updrafts in urban environments, including development and testing of new autopilot firmware. He has also designed, implemented, and tested hardware and software for a safety assurance system for unmanned aircraft. His current research interests include Unmanned aerial systems, Micro aerial vehicles, Autonomous systems, Sensing control, Aerodynamics, Fluid mechanics.

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