The aerodynamic efficiency of wing can be improved by using morphing wing system actuated by smart material. Shape memory alloy (SMA) can be used in such system to replace conventional actuator in order to reduce the weight of the wing. SMA acts as an actuator, embedded inside the wing to achieve the desired camber profile during flight. This study explores the self-sensing capability of the SMA by changing the resistivity during actuation using voltage drop across the SMA as the input to the feedback system. The self-sensing system can reduce the weight and cost as sensors can be eliminated. The SMA actuator was controlled using Proportional-Integral-Derivative (PID) controller with LabVIEW software where the voltage drop across the SMA acts as input to control the shape of the wing. The calibration data was critical to design the morphing wing actuation for the wind tunnel testing. The data was also analyzed to determine the voltage required to change the geometry of the morphing wing and improve the aerodynamics behavior in terms of lift-to-drag (L/D) ratio. The wing model was tested at angle of attack between-12 degrees and 16 degrees at wind speed of 20m/s. The experimental results of wind tunnel testing showed that the morphing wing system produced improvement on lift, drag and lift-to-drag ratio as predicted from earlier work using computational fluid dynamics. L/D improved as much as 9.2 at 4 degrees AOA for SMA actuation of 3.5V and 10.79 at at 6 degrees AOA for SMA actuation of 4.8V.

This review paper aims to serve as a comprehensive guide on how to analyze the A320 aircraft dynamically and effects of gust in terms of stability, as well as the success of using adaptive control in various aircraft. Adaptive control methods, specifically Model Reference Adaptive Control (MRAC) and also Model Predictive Control (MPC), offer promising solutions to enhance the stability and resilience of aircraft under adverse conditions. These advanced control techniques have the big potential to significantly enhance the aircraft's ability to maintain stability and control in the face of the unforeseen dynamic variations. In short, this paper delves into several aspects that also include the aerodynamic properties of the A320 aircraft, longitudinal and lateral motions of the aircraft, implementation of the MRAC system for enhancing stability and sample investigation on the effects of wind gust on the A320 aircraft. By systematically exploring these aspects, this paper highlights the limitations of the traditional control methods and demonstrates how the adaptive control techniques such as MRAC and MPC could be effectively utilized to improve the stability of the various aircraft under failure conditions. The insights and guidelines presented in this study further contribute toward the advancement of control strategies in the aviation industry, subsequently promoting much safer and more reliable aircraft operations. The results presented in this review paper are a preliminary result to verify the model to implement MRAC and MPC in future works. The simulation used an A320 model that is disturbed by gust. The findings show that the pitch angle initially rises to its maximum and then eventually stabilizes to near zero after oscillating, which indicates the aircraft's nose moving up and down to counter the effect of the gust prior to its stabilization to its original position. This indicates that the aircraft is statically stable.

This paper presents the design and implementation of an onboard object detection system integrated with a fixed-wing unmanned aerial vehicle (UAV) flight controller. The system employs a Raspberry Pi 4 and Pi Camera 3 as a lightweight vision module running a fine-tuned YOLOv8n model for real-time aerial detection. A custom dataset of 83 annotated images was collected and used for transfer learning, achieving a mean Average Precision (mAP@50-95 = 0.871) across four target classes which are buildings, cars, houses and lakes. The optimized YOLOv8n model operates at 2-3 FPS with FP16 precision on the Raspberry Pi 4, maintaining stable inference and acceptable power consumption within an similar to 11 W system envelope. Field experiments verified onboard detection capability and operational stability under flight conditions. The results demonstrate the feasibility of deploying deep-learning-based vision models on compact, low-cost UAV platforms for aerial monitoring and environmental observation applications.

Design of morphing wing poses a multi -disciplinary challenge involving aerodynamics, structure, material, control and system integration. The design process requires iterations and trade-offs to achieve the optimal solution that meets the design objective. In this study, design methodology for a morphing wing as a high lift device using the shape memory alloy actuator (SMA) is presented. The use of SMA in the design offers greater advantage compared to conventional actuator but it also further increases the design complexity. For this research work, a novel high lift device is designed to fulfill the design requirements of a wing with flexible trailing edge deflection. Computational fluid dynamics analysis (CFD) is used to assess the changes of aerodynamics forces. Finite element analysis (FEA) is used to predict the structural changes required. The SMA actuator is designed to provide the required actuation force to achieve the trailing edge deflection. A wind tunnel testing is performed to verify the lift and drag coefficient produced by the high lift device. On the whole, it has been found that the novel design of high lift device is capable of improvement in lift coefficient and the experimental test has also demonstrated an increase of lift -to -drag (L/D) ratio at lower angle of attack of 4 degrees where the L/D for the original wing was 3.806 and the L/D for the wing with trailing edge down was 8.

In this paper, the thermomechanical characteristic behavior of a shape memory alloy (SMA) spring was studied. Under homogenous distribution of temperature by immersion in the hot and cold water, the thermal equilibrium of the SMA spring was obtained and its performance under different preloads applied was measured. The thermomechanical behaviors and properties of the SMA spring for one cycle were derived from the analysis of the displacement of contraction, pulling force produced and temperature versus response time through experimental tests. The experimental results showed that the performance of the SMA spring and the response time depend on the technique of the heating phase to activate it and the cooling phase to passivation it, as well as on the wire diameter and the preload applied. The maximum displacement contractions produced from 2.5 N and 1.5 N pulling forces for 0.51 mm and 0.38 mm wire diameter of the SMA spring were found as 49 mm and 35 mm respectively. The SMA spring was heated by increasing the temperature rate 0.3 degrees C H/s of water and the temperature was decreased by adding cold water at a rate -6.1 degrees C/s. The response time of the SMA springs that occurred at the temperature 74 degrees C and 82 degrees C were respectively 37 s and 50 s. The experimental results for both contraction-temperature and forcetime responses at different preload, as well as collection of contraction-forcetemperature responses to response time provide a good visualization as references for the design dimensioning and fabrication of the SMA spring as actuator, sensor and heat engine.

The aerospace industry's reliance on inspections for component safety and readiness prompts challenges in non-destructive testing (NDT), particularly on contoured surfaces. Conventional methods, such as ultrasonic and eddy current testing, require constant probe contact which leads to slow inspections and accuracy concerns. Additionally, technicians face risks during elevated point inspections, necessitating a safer and efficient solution. To address these challenges, this study proposes a specialized robotic arm for NDT inspections in aerospace. The robotic arm automates inspections, enhancing efficiency, accuracy, and technician safety. The research aims to validate the robotic arm's performance, certifying its capability for NDT inspections on curved surfaces which ushers in a new era of enhanced practices. Using CATIA software, the project progresses through preliminary, conceptual, and detailed design stages. The fabricated robotic arm integrates with a trajectory planning and feedback system, enabling curved surface scanning while maintaining a normal probe trajectory. The system yields a 4.3 percent of error emphasizing the system's precision, with rigorous testing using myRIO and infrared (IR) sensor confirming the robotic arm's ability to maintain a 2 -mm distance from the scanned surface. This validates the system's efficacy and its capacity to autonomously uphold a specified distance during scanning. This innovative robotic arm and control system significantly impact aviation NDT, improving inspection practices, safety, and industry standards. The study not only validates the robotic arm's effectiveness but also sets the stage for future innovations in robotic NDT, benefiting sectors reliant on quality control and safety. The dual emphasis on precision and safety underscores the transformative potential of this research.

Introduction Investigation of vibrational characteristics is important in the design of a structure for dynamic loading conditions. Objectives This research explains a comprehensive method of experimentally investigating modal properties of a shape memory alloy (SMA)-embedded 3D woven composite plate. Methods The SMA wire is embedded in three different 3D orthogonal interlock structures. Dynamic properties, such as the natural frequencies and the mode shapes, are obtained through the roving impact hammer method and the contribution of SMA and its positioning for improving modal properties is assessed. Also, the effect of binding yarns of different 3D configurations on modal properties is studied. Results SMA wire imparts a significant effect on dynamic properties as SMA at the center has given higher bending mode frequencies upon activation while the torsional mode frequencies are more affected when the SMA wire is embedded off-center. The binding yarns of 3D structures also play an important role in affecting dynamic properties as layer-to-layer interlocked structure shows higher increments in natural frequencies while the modified structure having strong interlocking of binding yarns with SMA wire has given the lower percentage increments as restricting SMA to contract upon activation. Conclusion Hence, the vibrational characteristics of SMA-embedded 3D woven composite plates are significantly affected by activating SMA wire depending upon the position of the SMA wire as well the 3D structure that holds the SMA wire.

The shape memory alloy (SMA) wire actuator is desirable to modify the structure properties and shape morphing ability particularly for the aircraft wing application. However, SMA wire embedded directly into a matrix system caused mismatch in coefficient of thermal expansion (CTE) which further led to delamination and structure failure issues. Thus, a soft material that integrated effectively with SMA actuator to achieve shape changing while resisting the external load is required. In this work, SMA wire is inserted through the gaps in corrugated 3D printed thermoplastic polyurethane (TPU) elastomeric structure to analyze the geometrical factors and its flexure performance. The flexure test results indicated that TPU with inactive SMA insertion has sustained higher flexure load with 21

Recently, 3D composites have gained prominence over 2D composites due to their remarkable through-the-thickness reinforcement that enhanced performances of structures subject to multi-directional stress conditions. However, it is at the expense of reduced in-plane properties. 3D composites also increased damage tolerance due to their high impact and delamination resistance properties, which are susceptible in 2D composites. In aeronautics, both are major concerns in primary structures such as lifting and control surfaces due to high vibrational loads from the airflow. Advancements in the aeroelasticity of aircraft structures show an increasing trend in using smart materials with composite structures for improved aeroelastic performance. An example is combining shape memory alloys (SMAs) with composites for improving damping, stiffness, and vibrational characteristics by utilizing stress generation and strain accommodation properties of SMAs in response to temperature and load, respectively. Published works are mostly numerical in nature, and experimental research is noticeably lacking as aeroelasticity is multidisciplinary and involves both structural and aerodynamic methodology. In this work, 3D composites with embedded SMA wires (for improved in-plane properties) are evaluated in terms of flutter performance in wind tunnel flutter testing under low airspeed conditions. Three 3D orthogonal interlock configurations with a different interlocking pattern of yarns with SMA wire were considered. These 3D configurations are layer-to-layer (L2L), through-the-thickness (TT), and a modified interlock (MF) structure that provides the strongest grip to SMA wire than L2L and TT. The effect of SMA positioning, at mid and near to trailing and leading edges of the cantilevered composite plate, on the aeroelastic flutter properties is also investigated. Results showed that activating SMA wires embedded in 3D structures have significantly improved post-flutter properties while there is a decrement in flutter speed and flutter frequency due to increased flexibility of deflected plate in the airflow by SMA-induced stresses. Among 3D structures, L2L with SMA near to trailing edge showed significant improvement in post-flutter properties by decreasing 22.2% in twist limit cycle oscillation (LCO) amplitude while L2L with SMA at mid showed a decrement of 9.5% for bending LCO amplitude. Hence, this work showed that embedding SMA is beneficial for mitigating the post-flutter vibrations but at the consequence of reduced flutter speed and frequency of flexible composite plate.

Insects use dynamic articulation and actuation of their abdomen and other appendages to augment aerodynamic flight control. These dynamic phenomena in flight serve many purposes, including maintaining balance, enhancing stability, and extending maneuverability. The behaviors have been observed and measured by biologists but have not been well modeled in a flight dynamics framework. Biological appendages are generally comparatively large, actuated in rotation, and serve multiple biological functions. Technological moving masses for flight control have tended to be compact, translational, internally mounted and dedicated to the task. Many flight characteristics of biological flyers far exceed any technological flyers on the same scale. Mathematical tools that support modern control techniques to explore and manage these actuator functions may unlock new opportunities to achieve agility. The compact tensor model of multibody aircraft flight dynamics developed here allows unified dynamic and aerodynamic simulation and control of bioinspired aircraft with wings and any number of idealized appendage masses. The demonstrated aircraft model was a dragonfly-like fixed-wing aircraft. The control effect of the moving abdomen was comparable to the control surfaces, with lateral abdominal motion substituting for an aerodynamic rudder to achieve coordinated turns. Vertical fuselage motion achieved the same effect as an elevator, and included potentially useful transient torque reactions both up and down. The best performance was achieved when both moving masses and control surfaces were employed in the control solution. An aircraft with fuselage actuation combined with conventional control surfaces could be managed with a modern optimal controller designed using the multibody flight dynamics model presented here.

To study the flight dynamics of a generic hybrid fixed-wing UAV, the full six-degrees-of-freedom equations of motion of the aircraft are derived. Unlike conventional fixed-wing aircraft or multirotor drones, the flight dynamics of the hybrid aircraft are influenced by both sets of propulsion systems - the main petrol engine and the 4 fixed-rotors. Hence, a derivation of the flight dynamics is presented here as a result of the contribution from both propulsion systems. For this initial attempt, the main petrol engine is fixed at its location and has the sole purpose of providing horizontal thrust only. The position of the petrol engine is located along the X-body axis hence, no moment is created about the center of gravity (CG) by the main horizontal thrust. The 4 fixed rotors, on the other hand, provide vertical thrust along the Z-body axis with the associated roll and yaw. All 4-rotors are positioned on the same X-Y plane on the aircraft body axis. The paper concludes with the aircraft 6 degrees-of-freedom mathematical model of the Vertical Take-off and Landing (VTOL) Fixed-Wing (FW) Unmanned Aerial Vehicle (UAV).

The flight performance limitations of fixed wing Unmanned Aerial Vehicles (UAV) and drones can be solved by merging the strength of both types of vehicles. By making a fixed wing UAV capable of vertical takeoff and land (VTOL), the flight-envelop and mission capabilities can be increased. Although some researchers have proposed designing a totally new hybrid aircraft with these capabilities, the work published here proposed incorporating a relatively simple quadrotor type system on existing successful fixed wing airframe to provide the VTOL capability, capitalizing the best from an already successful UAV. The study is focused on the converted aircraft longitudinal motion during transition from hover to forward flight. XFLR5 was used to obtain the aerodynamic coefficients and then, MATLAB and SIMULINK simulated the flight dynamic responses. The results show that the best transition performance is achieved when both the 4 rotors and the internal combustion (IC) engine are engaged together during the transition, producing no lost in altitude. The study also found that in the event the 4 rotors failed simultaneously during the transition, the aircraft can still complete the transition with only the IC engine functioning at 40N of thrust.

A conceptual design of Stirling engine suitable for onboard aircraft application is the motivation behind this study. The aim is to evaluate the suitability of the system to be integrated in aircraft as part of energy contributor by recycling the waste thermal energy. A parametric evaluation of an established Wobble-Yoke Stirling Engine state space model was performed to determine a suitable pre-compensator design that is able to produce the highest power output given the size and mass constraint. Simulation was performed using MATLAB in order to analyze the dynamic properties of the engine as a closed-loop system, with temperature, pressure and damping coefficient acting as controlling parameters. The parametric evaluation was conducted to determine the effect of assemble mass of piston, maximum displacement of piston and viscous damping coefficient to the performance of the system. The methodology can be used in the conceptual design process in order to determine the sizing and power output of the stirling engine system.

Many drone platforms have matured to become nearly optimal flying machines with only modest improvements in efficiency possible. “Chimera” craft combine fixed wing and rotary wing characteristics while being substantially less efficient than both. The increasing presence of chimeras suggests that their mix of vertical takeoff, hover, and more efficient cruise is invaluable to many end users. We discuss the opportunity for flapping wing drones inspired by large insects to perform these mixed missions. Dragonflies particularly are capable of efficiency in all modes of flight. We will explore the fundamental principles of dragonfly flight to allow for a comparison between proposed flapping wing technological solutions and a flapping wing organism. We chart one approach to achieving the next step in drone technology through systems theory and an appreciation of how biomimetics can be applied. New findings in dynamics of flapping, practical actuation technology, wing design, and flight control are presented and connected. We show that a theoretical understanding of flight systems and an appreciation of the detail of biological implementations may be key to achieving an outcome that matches the performance of natural systems. We assert that an optimal flapping wing drone, capable of efficiency in all modes of flight with high performance upon demand, might look somewhat like an abstract dragonfly.

The corrected figure is given below.