To enable a carrier-based unmanned aerial vehicle (UAV) to track the desired glide trajectory and safely land on the deck with the presence of system faults, this paper proposes a neural network-based adaptive sliding mode fault-tolerant control (NASFTC) method. Firstly, the dynamic model of the carrier -based UAV, the actuator fault model, the additional unknown fault model, and the control framework of the automatic carrier landing system (ACLS) were developed. Subsequently, controllers for both longitudinal and lateral channels were designed by using the NASFTC method. The controller consists of three parts: the adaptive laws for compensating the actuator faults, the RBF neural network for compensating the additional unknown faults, and the sliding mode method for ensuring overall trajectory tracking. Then, the Lyapunov function theorem was applied to carry out the stability analysis. Finally, comparative simulations under three different scenarios were conducted. The comparative results show the effectiveness of the proposed NASFTC method, which has fault-tolerant ability and can successfully control the aircraft to execute carrier landing task regardless of the actuator partial loss fault and the additional unknown fault.

Carrier-based unmanned aerial vehicle (UAV) is prone to faults during missions, leading to abrupt changes in flight dynamic and increasing the difficulty of landing. To address this, this paper proposes a fault-tolerant carrier landing control method with fixed-time convergence and prescribed performance abilities. This method integrates a fault disturbance observer and a prescribed performance controller. The fault disturbance observer estimates and compensates for disturbances caused by faults, enhancing fault tolerance. Meanwhile, the prescribed performance controller ensures that the attitude tracking error remains within predefined bounds despite disturbances, ensuring safe landing. A carrier landing control system based on this method is developed for automatic carrier landing tasks. Numerical simulation tests demonstrate that the proposed control scheme can achieve precise and rapid landing control even with elevator bias and the aileron partial loss faults. Finally, by using a simulated wingtip damage mechanism to induce faults, real flight tests are carried out. The flight tests results demonstrate that the UAV maintains stable attitude and trajectory tracking despite the presence of faults, further verifying the effectiveness and reliability of the proposed method, establishing a foundation for future practical engineering applications.

The spanwise morphing wing can change its aerodynamic shape to suit its flight environment, thereby having the potential to improve the flight performance of the aircraft, especially in gusty conditions. To investigate the potential of morphing wings, the aerodynamic performance of a spanwise morphing wing with a flapping wingtip in a gust environment was analyzed in this paper. The aerodynamic characteristics of the morphing wing are hard to measure accurately, and thus a wind tunnel test was carried out to study the influences of morphing parameters, such as the morphing length, amplitude and frequency on the gust alleviation effect. The flow mechanism of the designed spanwise morphing wing was analyzed in detail by the instantaneous lift results of the wind tunnel test and the flow field results of the CFD method. The results have shown that with appropriate morphing parameters, the spanwise morphing wing designed in this paper can effectively achieve gust alleviation during flight. The conclusions obtained in this paper can be useful guidance for the design of morphing aircraft.

Carrier-based unmanned aerial vehicles (UAVs) require precise evaluation methods for their landing and arresting safety due to their high autonomy and demanding reliability requirements. In this paper, an efficient and accurate simulation method is presented for studying the arresting hook engaging arresting cable process. The finite element method and multibody dynamics (FEM-MBD) approach is employed. By establishing a rigid–flexible coupling model encompassing the UAV and arresting gear system, the simulation model for the engagement process is obtained. The model incorporates multiple coordinate systems to effectively capture the relative motion between the rigid and flexible components. The model considers the material properties, arresting gear system characteristics, and UAV state during engagement. Verification is conducted by comparing simulation results with experimental data from a referenced arresting hook rebound. Finally, simulations are performed under different touchdown points and roll angles of the UAV to analyze the stress distribution of the hook, center of gravity variations, and the tire touch and rollover cable response. The proposed rigid–flexible coupling arresting dynamics model in this paper enables the effective analysis of the dynamic behavior during the arresting hook engaging arresting cable process.

Landing control for carrier-based unmanned aerial vehicles (UAV) is highly challenging due to severe environment disturbance. This paper proposes a reinforcement learning-based anti-disturbance approach to solve these problems. A relative motion model is established, integrating UAV and carrier dynamics, air wake disturbances, and deck motion, along with an Automatic Carrier Landing System (ACLS). A robust trajectory tracking controller is designed using the Deep Deterministic Policy Gradient (DDPG) algorithm to improve the landing system's precision and reliability. The proposed control framework comprises three components: the UAV actuation system, flight dynamics model, and the DDPG-based controller. Numerical simulations were conducted to evaluate performance under oscillating carrier deck motion, and the landing accuracy of the proposed method is compared with that of the other methods. A comparative analysis has been conducted, and the results indicate that the DDPG-based approach exhibits enhanced robustness and accuracy, effectively mitigating disturbances and ensuring precise landings. This study validates the proposed strategy as a promising solution for UAV carrier landing in challenging conditions.

The engagement of the arresting hook with the arresting cable is a critical maneuver that is essential to the safe operation of aircraft landing on aircraft carrier. A comprehensive understanding of the engagement process dynamics is necessary to optimize landing performance and ensure the safety and efficiency of carrier operations. In this paper, an efficient and accurate simulation and analysis method is presented for studying the arresting hook engaging arresting cable process. The Finite Element Method and Multibody Dynamics (FEM-MBD) approach is employed. By establishing a rigid-flexible coupling model encompassing the aircraft frame, arresting hook, carrier deck and arresting gear system, the dynamic model for the engagement process is obtained. The model incorporates multiple coordinate systems to effectively capture the relative motion between the rigid and flexible components, enabling a thorough understanding of the dynamics characteristics. The analysis conducted in this paper takes into account various factors, including the material properties of the components, the characteristics of the arresting gear system, and the state of the aircraft during the engagement process. The analysis method is verified by comparing the simulation results with experiments of arresting hook rebound obtained from reference. Finally, simulations are performed to analyze the engagement process under different touchdown points and rolling angle of aircraft. The simulation results provide valuable insights into the distribution of stresses during the arresting hook and cable engagement, the center of gravity variations, as well as the response of the tire touch and rollover cable under specific scenarios. The proposed rigid-flexible coupling arresting dynamics model in this paper enables effective analysis of the dynamic behavior during arresting hook engaging arresting cable. The results obtained from this analysis offer valuable insights into the performance of the engagement process, which can be used to improve the design of carrier-based aircraft and techniques for carrier landing.