ABSTRACT
[...]the following 13 conference papers have been selected for publication in this peer-reviewed special issue: Topczewski S., Żugaj M.;Bibik P., “Impact of Actuators Backlash on the Helicopter Control During Landing on the Moving Vessel Deck” Kopecki G., “Aircraft Control With the Use of Model Reference Adaptive Control” Rodzewicz M., “Comparative fatigue properties estimation of composite structural nodes” Kowalski M., Goraj Z.;Goliszek B., “The use of FEA and semi-empirical equations for weight estimation of a passenger aircraft” Olejnik A., Dziubiński, A.: Kiszkowiak. Ł., “CFD simulation of engine nacelle cooling on pusher configuration aircraft” Goraj Z., Kowalski M., Kiszkowiak Ł.;Olejnik A., “Simulation of a passenger aircraft flight with the wing tip cut” Bridel G., Goraj Z.;Kiszkowiak Ł., Brevot Jean-G. and Devaux J., Szczepański C., Vrchota P., “Air combat training - high energy at lowest cost” Kwiek A., Galiński C., Bogdański K., Hajduk J.;Tarnowski A., “Results of Simulation and Scaled Flight Tests Performed on a Rocket-Plane at High Angles of Attack” Rogalski T., Rzucidło P., Noga St.;Prusik J., “Unmanned Aircraft Automatic Flight Control Algorithm in an Immelmann Manoeuvre” Kretov A., “Sensitivity Factors of Aircraft Mass for the Conceptual Design” Noga St., Maciejowska K.;Rogalski T., “Vibration Analysis of an Aviation Engine Turbine Shaft Shield” Samolej S., Dec G., Rzońca D., Majka A.;Rogalski T., “Regular Graph-based Free Route Flight Planning Approach” Pieniążek J.;Cieciński P., “Safety analysis of the optionally-piloted airplane landing” The articles deal with different solutions for future aerospace challenges in the areas of novel configuration, aerodynamics, design methods, multidisciplinary optimization, UAV and stress analysis. [...]I would like to thank the Editor-in-Chief of the AEAT, Prof. Philip Webb, for his agreement, and support of all editorial team of AEAT in making this issue possible.
ABSTRACT
This paper presents a heterogeneous configuration of the multirotor unmanned aerial system (UAS) that features the combined characteristics of the helicopter and quadrotor in a single multirotor design, featuring the endurance and energy efficiency similar to a helicopter, while keeping the mechanical simplicity, control, and manoeuvrability of the standard quadrotor. Power needed for a rotorcraft to hover has the inverse relation with the rotor disc. Therefore, multiple small rotors of the quadrotor are energetically outperformed by a large rotor of the helicopter, for a similar size. Designing the stable control system for such a dynamically complex multirotor configuration remains the main challenge as the studies previously carried out on these designs have successfully demonstrated energy efficiency but at the cost of degraded attitude control. Advancements in the energetics of the multirotor results in enhanced endurance and range that could be highly effective in remote operation applications. However, a stable control system is required for accurate positioning. In this paper, a cascaded PID control approach is proposed to provide the control solution for this heterogeneous multirotor. Automatic tuning is proposed to design the PID controller for each loop of the cascade structure. A relay feedback experiment is conducted in a controlled environment, followed by identification of the open-loop frequency response and estimation of dynamics. Subsequently, PID controllers are tuned through approximated models with the help of tuning rules. A custom-designed flight controller is used to experimentally implement the proposed control structure. Presented experimental results demonstrate the efficacy of the proposed control strategy for heterogeneous multirotor UAS.