Abstracts of Journal Articles - Accepted for Publication

A Review of Control Strategies Used for Morphing Aircraft Applications

MS Parancheerivilakkathil, JS Pilakkadan, RM Ajaj (Khalifa University of Science and Technology, UAE), MR Amoozgar (University of Nottingham), D Asadi (Adana Alparslan Turkes Science and Technology University, Turkey), Y Zweiri (Khalifa University of Science and Technology, UAE) & MI Friswell (Swansea University)

Chinese Journal of Aeronautics

This paper reviews the various control algorithms and strategies used for fixed-wing morphing aircraft applications. It is evident from the literature that the development of control algorithms for morphing aircraft technologies focused on three main areas. The first area is related to precise control of the shape of morphing concepts for various flight conditions. The second area is mainly related to the flight dynamics, stability, and control aspects of morphing aircraft. The third area deals mainly with aeroelastic control using morphing concepts either for load alleviation purposes and/or to control the instability boundaries. The design of controllers for morphing aircraft/wings is very challenging due to the large changes that can occur in the structural, aerodynamic, and inertial characteristics. In addition, the type of actuation system and actuation rate/speed can have a significant effect on the design of such controllers. The aerospace community is in strong need of such a critical review especially as morphing aircraft technologies move from fundamental research at a low technology readiness level (TRL) to real-life applications. This critical review aims to identify research gaps and propose future directions. In this paper, research activities/papers are categorized according to the control strategy used. This ranges from simple PID controllers at one end to complex robust adaptive controllers and deep learning algorithms at the other end. This includes analytical, computational, and experimental studies. In addition, the various dynamic models used and their fidelities are highlighted and discussed.

High-energy Orbit Harvesting with Torsionally Coupled Mistuned Pendulums

PV Malaji (V P Dr. P G Halakatti College of Engineering & Technology, India), MI Friswell (Swansea University), S Adhikari (University of Glasgow) & G Litak (Lublin University of Technology, Poland)

Journal of Vibration Engineering Technologies

This article demonstrates the possibility of energy harvesting by mistuned pendulums with torsional coupling. Two pendulums of different lengths with coils and magnets at the pivots are used as electromagnetic harvesters. The ambient energy source to the system is considered in the form of harmonic base excitations. Torsional coupling is achieved by connecting the pendulums with a torsional spring. The non-linearity of the underlying dynamics arises due to mechanical coupling and forcing amplitude. Numerical results are presented to analyze the performance of the pendulum energy harvester under different torsional coupling values. Three different zones were identified based on coupling value, power output and frequency bandwidth. Based on the requirement of power magnitude and bandwidth, one can select a suitable zone. The dynamic behaviour of the pendulums in each zone is shown by bifurcation and phase diagrams. The results indicate periodic and quasi-periodic oscillations for different values of torsional coupling. The effect of load resistance on the energy harvesting and dynamics of the pendulums is presented. The harmonic balance method results are presented to verify the existence of high energy orbit solutions in respective zones. A good agreement between numerical and harmonic balance results is observed. The optimal choice of torsional coupling, load resistance along with optimal initial conditions enables the harvesting of more power over a broader frequency band. Cross recurrence plots are also presented to show synchronisation state of pendulums.

Link to paper using doi: 10.1007/s42417-022-00811-6