With the steady increase of air traffic column, an auxiliary decision tool is required to compensate the operation redundancy deficiency of more sectors of air traffic control. To solve the problem of nonconflict high-density departure and arrival traffic flow, this method is expected to rapidly establish and maintain safe separation with more flexible changing strategies for aircraft heading and speed. This paper proposes an improved reinforcement learning framework to achieve conflict detection and resolution. The proposed framework includes the first development of an air traffic flow model based on a multiagent Markov decision process. The goal reward function was then maximized by improved Monte-Carlo tree search combined with an upper confidence bound tree. Three simulation scenarios were designed for illustrating the improvements of the proposed algorithm, with the results indicating that the algorithm could establish and maintain safe separation between 20 agents in the simplified hexagon-shaped airspace of Huadong, China. Furthermore, the proposed method was demonstrated to reduce the number of conflicts between aircraft agents by up to 26.32% compared to previous research.
{"title":"An Efficient Aircraft Conflict Detection and Resolution Method Based on an Improved Reinforcement Learning Framework","authors":"Qiucheng Xu, Zhangqi Chen, Fangfang Li, Zhiyuan Shen, Wenbin Wei","doi":"10.1155/2023/6643903","DOIUrl":"https://doi.org/10.1155/2023/6643903","url":null,"abstract":"With the steady increase of air traffic column, an auxiliary decision tool is required to compensate the operation redundancy deficiency of more sectors of air traffic control. To solve the problem of nonconflict high-density departure and arrival traffic flow, this method is expected to rapidly establish and maintain safe separation with more flexible changing strategies for aircraft heading and speed. This paper proposes an improved reinforcement learning framework to achieve conflict detection and resolution. The proposed framework includes the first development of an air traffic flow model based on a multiagent Markov decision process. The goal reward function was then maximized by improved Monte-Carlo tree search combined with an upper confidence bound tree. Three simulation scenarios were designed for illustrating the improvements of the proposed algorithm, with the results indicating that the algorithm could establish and maintain safe separation between 20 agents in the simplified hexagon-shaped airspace of Huadong, China. Furthermore, the proposed method was demonstrated to reduce the number of conflicts between aircraft agents by up to 26.32% compared to previous research.","PeriodicalId":13748,"journal":{"name":"International Journal of Aerospace Engineering","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135305822","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zhe Hu, Liang Xiao, Jun Guan, Wenjun Yi, Hongqiao Yin
In this paper, a novel guidance law based on a reinforcement learning (RL) algorithm is presented to deal with the maneuvering target interception problem using a deep deterministic policy gradient descent neural network. We take the missile’s line-of-sight (LOS) rate as the observation of the RL algorithm and propose a novel reward function, which is constructed with the miss distance and LOS rate to train the neural network off-line. In the guidance process, the trained neural network has the capacity of mapping the missile’s LOS rate to the normal acceleration of the missile directly, so as to generate guidance commands in real time. Under the actor-critic (AC) framework, we adopt the twin-delayed deep deterministic policy gradient (TD3) algorithm by taking the minimum value between a pair of critics to reduce overestimation. Simulation results show that the proposed TD3-based RL guidance law outperforms the current state of the RL guidance law, has better performance to cope with continuous action and state space, and also has a faster convergence speed and higher reward. Furthermore, the proposed RL guidance law has better accuracy and robustness when intercepting a maneuvering target, and the LOS rate is converged.
{"title":"Intercept Guidance of Maneuvering Targets with Deep Reinforcement Learning","authors":"Zhe Hu, Liang Xiao, Jun Guan, Wenjun Yi, Hongqiao Yin","doi":"10.1155/2023/7924190","DOIUrl":"https://doi.org/10.1155/2023/7924190","url":null,"abstract":"In this paper, a novel guidance law based on a reinforcement learning (RL) algorithm is presented to deal with the maneuvering target interception problem using a deep deterministic policy gradient descent neural network. We take the missile’s line-of-sight (LOS) rate as the observation of the RL algorithm and propose a novel reward function, which is constructed with the miss distance and LOS rate to train the neural network off-line. In the guidance process, the trained neural network has the capacity of mapping the missile’s LOS rate to the normal acceleration of the missile directly, so as to generate guidance commands in real time. Under the actor-critic (AC) framework, we adopt the twin-delayed deep deterministic policy gradient (TD3) algorithm by taking the minimum value between a pair of critics to reduce overestimation. Simulation results show that the proposed TD3-based RL guidance law outperforms the current state of the RL guidance law, has better performance to cope with continuous action and state space, and also has a faster convergence speed and higher reward. Furthermore, the proposed RL guidance law has better accuracy and robustness when intercepting a maneuvering target, and the LOS rate is converged.","PeriodicalId":13748,"journal":{"name":"International Journal of Aerospace Engineering","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135691530","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Dual numbers were applied to the dynamics of a rigid-flexible combination system (RFCS) with time-varying configuration in this paper. The six-dimensional spinor form of the motion of flexible modules, including the dual vector, dual momentum, dual inertia operator, dual coupling coefficient operator, and dual-modal coordinates, was derived using the dual numbers that could represent spiral motion in a compact form. On this basis, the integrated dynamic model of a rigid-flexible combination system with a time-varying configuration was proposed. And then, the relative dynamics equations between two rigid-flexible combination systems which both have time-varying configuration were provided. An on-orbit assembly mission of flexible modules transported and operated by free-flying space robots (FFSRs) is presented as an exemplary application of relative dynamics. Simulation results illustrate the complex coupling effects on the relative motion between two rigid-flex combination systems with time-varying configuration.
{"title":"Integrated Dynamics of Space Rigid-Flex Combination System with Time-Varying Configuration","authors":"Yaen Xie, Xianliang Zhang, Xiangshuai Song, Xiaobin Lian, Jian Zhang","doi":"10.1155/2023/9980780","DOIUrl":"https://doi.org/10.1155/2023/9980780","url":null,"abstract":"Dual numbers were applied to the dynamics of a rigid-flexible combination system (RFCS) with time-varying configuration in this paper. The six-dimensional spinor form of the motion of flexible modules, including the dual vector, dual momentum, dual inertia operator, dual coupling coefficient operator, and dual-modal coordinates, was derived using the dual numbers that could represent spiral motion in a compact form. On this basis, the integrated dynamic model of a rigid-flexible combination system with a time-varying configuration was proposed. And then, the relative dynamics equations between two rigid-flexible combination systems which both have time-varying configuration were provided. An on-orbit assembly mission of flexible modules transported and operated by free-flying space robots (FFSRs) is presented as an exemplary application of relative dynamics. Simulation results illustrate the complex coupling effects on the relative motion between two rigid-flex combination systems with time-varying configuration.","PeriodicalId":13748,"journal":{"name":"International Journal of Aerospace Engineering","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135733807","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Landing control of unmanned aerial vehicles (UAVs) is challenging because of the strong nonlinear dynamics, multivariable, model uncertainties, wind variations, and sensor noise. Motivated by this fact, this paper investigates an automatic landing system (ALS) that includes trajectory generation and guidance law for the first flight test of a turbine-based combined cycle technology demonstrator. Specifically, the control scheme increases the original model’s order to generate a reasonable monotone-decreasing throttle reference flare trajectory by the pseudospectral method. Subsequently, the guidance law based on innovative multivariable active disturbance rejection control is designed to robustly track the reference altitude and velocity simultaneously with high accuracy. The multivariable extended state observer (ESO) incorporated decoupling algorithm enhances the estimation capability and accuracy of potential problem in cross-coupling dynamics compared to the traditional ESO. It is proven that the closed-loop error dynamic has bounded-input bounded-output stability and an explicit upper bound is given. Numerical simulation verifies that the presented approach has better robustness and higher tracking accuracy for external disturbances and parametric uncertainties than the existing benchmark autolanding controller. Finally, flight tests show that the proposed ALS can land the vehicle effectively and safely under severe wind conditions.
{"title":"Automatic Landing System Design for Unmanned Fixed-Wing Vehicles via Multivariable Active Disturbance Rejection Control","authors":"Zonghua Sun, Liaoni Wu, Yancheng You","doi":"10.1155/2023/9395447","DOIUrl":"https://doi.org/10.1155/2023/9395447","url":null,"abstract":"Landing control of unmanned aerial vehicles (UAVs) is challenging because of the strong nonlinear dynamics, multivariable, model uncertainties, wind variations, and sensor noise. Motivated by this fact, this paper investigates an automatic landing system (ALS) that includes trajectory generation and guidance law for the first flight test of a turbine-based combined cycle technology demonstrator. Specifically, the control scheme increases the original model’s order to generate a reasonable monotone-decreasing throttle reference flare trajectory by the pseudospectral method. Subsequently, the guidance law based on innovative multivariable active disturbance rejection control is designed to robustly track the reference altitude and velocity simultaneously with high accuracy. The multivariable extended state observer (ESO) incorporated decoupling algorithm enhances the estimation capability and accuracy of potential problem in cross-coupling dynamics compared to the traditional ESO. It is proven that the closed-loop error dynamic has bounded-input bounded-output stability and an explicit upper bound is given. Numerical simulation verifies that the presented approach has better robustness and higher tracking accuracy for external disturbances and parametric uncertainties than the existing benchmark autolanding controller. Finally, flight tests show that the proposed ALS can land the vehicle effectively and safely under severe wind conditions.","PeriodicalId":13748,"journal":{"name":"International Journal of Aerospace Engineering","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136108293","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Rotor blades are one of the key components of helicopter. If the blades are damaged, the safety and reliability of the helicopter will be seriously affected. Therefore, it is necessary to investigate the damage identification of the rotating blades. In this paper, a rotating cantilever beam is used to model the rotor blade. Based on the assumed mode method and Hamilton’s principle, the equation of motion is formulated, and the correctness of the model is verified by numerical and experimental studies. Altogether, two methods are used to identify the damages on the blade. The first one is the cluster analysis method based on the fuzzy C-mean theory. In order to reduce the dimension of the signal features, the singular value decomposition is introduced. The second method is the curvature of frequency response function method that can be used to determine the exact position of damages. Simulation results show that one can use fuzzy C-mean method to determine whether there is damage on the blade firstly and then determine the exact position of the damage through the curvature of frequency response function method.
{"title":"Damage Identification of Rotating Blades Based on Fuzzy C-Means and Frequency Response Function Curvature Methods","authors":"Ruize Cui, Zefeng Wang, Zhiguang Song","doi":"10.1155/2023/6011397","DOIUrl":"https://doi.org/10.1155/2023/6011397","url":null,"abstract":"Rotor blades are one of the key components of helicopter. If the blades are damaged, the safety and reliability of the helicopter will be seriously affected. Therefore, it is necessary to investigate the damage identification of the rotating blades. In this paper, a rotating cantilever beam is used to model the rotor blade. Based on the assumed mode method and Hamilton’s principle, the equation of motion is formulated, and the correctness of the model is verified by numerical and experimental studies. Altogether, two methods are used to identify the damages on the blade. The first one is the cluster analysis method based on the fuzzy C-mean theory. In order to reduce the dimension of the signal features, the singular value decomposition is introduced. The second method is the curvature of frequency response function method that can be used to determine the exact position of damages. Simulation results show that one can use fuzzy C-mean method to determine whether there is damage on the blade firstly and then determine the exact position of the damage through the curvature of frequency response function method.","PeriodicalId":13748,"journal":{"name":"International Journal of Aerospace Engineering","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136108706","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper studies the model-free robust adaptive cruise control problem of a vehicle with unknown nonlinear dynamics and disturbances. First, under backstepping control framework, the position tracking errors with different spacing strategies are used to design a virtual control law, which provides a velocity reference. Then, a novel data-driven sliding surface whose parameters are updated by designing estimation algorithm is developed to handle the unknown uncertainties and disturbances. Finally, the model-free robust backstepping adaptive cruise control (MFRB-ACC) method including PI control, model-free control, and robust control is designed. The novelty of the proposed control technique lies in its strong robustness, which is not based on the precise vehicle model. The designed data-driven sliding surface releases the necessity for the accurate mathematical model of the vehicle and guarantees the inherent robustness of the controller, in particular to uncertainties, modelling error, or external disturbance. Moreover, the designed controller contains three terms such that it has an effective decoupling ability and strong robustness. The effectiveness and superiority of the designed MFRB-ACC method are validated on MATLAB, and the simulation results show that compared to the PID algorithm, the designed MFRB-ACC algorithm can track its preceding vehicle with lower tracking error under different spacing strategies, different operating conditions, and low sampling frequencies. Especially at a sampling frequency of 0.1 s, the error under the PID-ACC increases from 0.2 m at a sampling frequency of 0.01 s to 2 m, and the error under MFRB-ACC has little change compared to the error at a sampling frequency of 0.01 s.
研究了具有未知非线性动力学和扰动的车辆的无模型鲁棒自适应巡航控制问题。首先，在反步控制框架下，利用不同间距策略下的位置跟踪误差设计了虚拟控制律，为速度控制提供了参考。然后，开发了一种新的数据驱动滑动表面，其参数通过设计估计算法来更新，以处理未知的不确定性和扰动。最后，设计了无模型鲁棒反推自适应巡航控制（MFRB-ACC）方法，包括PI控制、无模型控制和鲁棒控制。所提出的控制技术的新颖性在于其强大的鲁棒性，而不是基于精确的车辆模型。设计的数据驱动滑动表面释放了对车辆精确数学模型的必要性，并保证了控制器的固有鲁棒性，特别是对不确定性、建模误差或外部扰动的鲁棒性。此外，所设计的控制器包含三项，使其具有有效的解耦能力和较强的鲁棒性。在MATLAB上验证了所设计的MFRB-ACC方法的有效性和优越性，仿真结果表明，与PID算法相比，在不同的间距策略、不同的运行条件和低采样频率下，所设计的MF RB-ACC算法能够以较低的跟踪误差跟踪前车。尤其是在0.1的采样频率下 s、 PID-ACC下的误差从0.2增加 m，采样频率为0.01 s到2 m、 并且MFRB-ACC下的误差与0.01的采样频率下的误差相比几乎没有变化 s
{"title":"Model-Free Robust Backstepping Adaptive Cruise Control","authors":"Yanan Zhang, Jiacheng Song","doi":"10.1155/2023/8839650","DOIUrl":"https://doi.org/10.1155/2023/8839650","url":null,"abstract":"This paper studies the model-free robust adaptive cruise control problem of a vehicle with unknown nonlinear dynamics and disturbances. First, under backstepping control framework, the position tracking errors with different spacing strategies are used to design a virtual control law, which provides a velocity reference. Then, a novel data-driven sliding surface whose parameters are updated by designing estimation algorithm is developed to handle the unknown uncertainties and disturbances. Finally, the model-free robust backstepping adaptive cruise control (MFRB-ACC) method including PI control, model-free control, and robust control is designed. The novelty of the proposed control technique lies in its strong robustness, which is not based on the precise vehicle model. The designed data-driven sliding surface releases the necessity for the accurate mathematical model of the vehicle and guarantees the inherent robustness of the controller, in particular to uncertainties, modelling error, or external disturbance. Moreover, the designed controller contains three terms such that it has an effective decoupling ability and strong robustness. The effectiveness and superiority of the designed MFRB-ACC method are validated on MATLAB, and the simulation results show that compared to the PID algorithm, the designed MFRB-ACC algorithm can track its preceding vehicle with lower tracking error under different spacing strategies, different operating conditions, and low sampling frequencies. Especially at a sampling frequency of 0.1 s, the error under the PID-ACC increases from 0.2 m at a sampling frequency of 0.01 s to 2 m, and the error under MFRB-ACC has little change compared to the error at a sampling frequency of 0.01 s.","PeriodicalId":13748,"journal":{"name":"International Journal of Aerospace Engineering","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43160077","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Recently, flow control using vortex generators (VGs) and a Gurney flap (GF) has received considerable attention, but independently. The purpose of this study is to perform a numerical investigation into the lift augmentation effects of a tiltrotor wing with the combination of VGs and GF. The numerical results were obtained with the Reynolds-averaged Navier-Stokes (RANS) equations, and the turbulence was solved by the Spalart-Allmaras one-equation turbulence model. The separate and joint performances of these two control devices at different angles of attack are determined. It is shown that the combined configuration can provide greater lift augmentation than either device individually. Compared with the baseline wing, the implementation of both devices increases the stall angle of attack from 10° to 22°, and the maximum lift coefficient is improved by 82.33%.
{"title":"Lift Augmentation on a Tiltrotor Wing Using the Combination of Vortex Generators and Gurney’s Flap","authors":"Hao Chen, Siliang Du, Zhong Chen","doi":"10.1155/2023/6646817","DOIUrl":"https://doi.org/10.1155/2023/6646817","url":null,"abstract":"Recently, flow control using vortex generators (VGs) and a Gurney flap (GF) has received considerable attention, but independently. The purpose of this study is to perform a numerical investigation into the lift augmentation effects of a tiltrotor wing with the combination of VGs and GF. The numerical results were obtained with the Reynolds-averaged Navier-Stokes (RANS) equations, and the turbulence was solved by the Spalart-Allmaras one-equation turbulence model. The separate and joint performances of these two control devices at different angles of attack are determined. It is shown that the combined configuration can provide greater lift augmentation than either device individually. Compared with the baseline wing, the implementation of both devices increases the stall angle of attack from 10° to 22°, and the maximum lift coefficient is improved by 82.33%.","PeriodicalId":13748,"journal":{"name":"International Journal of Aerospace Engineering","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46452429","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper studies the multiple geosynchronous spacecraft refueling problem (MGSRP) with multiple servicing spacecraft (Ssc) and fuel depots (FDs). In the mission scenario, multiple Ssc and FDs are parked in the geosynchronous Earth orbit (GEO) initially. Ssc start from FDs and maneuver to visit and refuel multiple GEO targets with known demands. These capacitated Ssc are expected to rendezvous with fuel-deficient GEO targets and FDs for the purpose of delivering the fuel stored in FDs to GEO targets. The objective is to find a set of Pareto-optimal solutions with minimum fuel cost and mission duration. The MGSRP is a much more complex variant of multidepot vehicle routing problems mixing discrete and continuous variables. A two-nested optimization model is built. We propose a new multiobjective hybrid particle swarm optimization to solve the outer-loop problem, and the design variables are the refueling sequence, task assignment, time distribution, and locations of FDs. In the inner-loop problem, branch and bound method is used to find the optimal decision variable for a given outer-loop solution. Finally, numerical simulations are presented to illustrate the effectiveness and validity of the proposed approach.
{"title":"Multiobjective Mission Planning for Multiple Geosynchronous Spacecraft Refueling","authors":"Linjie Kong, Yang Zhou","doi":"10.1155/2023/6623461","DOIUrl":"https://doi.org/10.1155/2023/6623461","url":null,"abstract":"This paper studies the multiple geosynchronous spacecraft refueling problem (MGSRP) with multiple servicing spacecraft (Ssc) and fuel depots (FDs). In the mission scenario, multiple Ssc and FDs are parked in the geosynchronous Earth orbit (GEO) initially. Ssc start from FDs and maneuver to visit and refuel multiple GEO targets with known demands. These capacitated Ssc are expected to rendezvous with fuel-deficient GEO targets and FDs for the purpose of delivering the fuel stored in FDs to GEO targets. The objective is to find a set of Pareto-optimal solutions with minimum fuel cost and mission duration. The MGSRP is a much more complex variant of multidepot vehicle routing problems mixing discrete and continuous variables. A two-nested optimization model is built. We propose a new multiobjective hybrid particle swarm optimization to solve the outer-loop problem, and the design variables are the refueling sequence, task assignment, time distribution, and locations of FDs. In the inner-loop problem, branch and bound method is used to find the optimal decision variable for a given outer-loop solution. Finally, numerical simulations are presented to illustrate the effectiveness and validity of the proposed approach.","PeriodicalId":13748,"journal":{"name":"International Journal of Aerospace Engineering","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43385762","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hong Xiao, Hongwei Guo, Mingqi Li, Yu Zhang, Rongqiang Liu, Jianguo Tao
The variable-sweep wing is very attractive for cross-speed domain aircraft. The shear-sliding rigid-flexible coupled skin variable-sweep wing and its associated mechanism are designed and optimized. The variable-sweep wing has smooth continuous deformation and rigid-flexible coupling features. The calculation model of the sliding skin patch segmentation strategy is established, and the aerodynamic characteristics of the two-dimensional airfoil before and after the deformation of the wing skin are analyzed. According to the deformation characteristics of sliding skin, the configuration of the associated mechanism is determined, and the kinematic characteristics of the reference points of each skin are calculated. The kinematic simulation verifies the force of the mechanism model at the joint of skin surfaces during the deformation process. Considering the aerodynamic heat at supersonic speed, the heat transfer, heat distribution, and structural thermal modes between the flow field and the skin are calculated based on the finite element method. The dynamic characteristics of the swept wing with different flight speeds and different morphologies are analyzed. The natural frequencies are found to be reduced by about 30% to 50% compared to cold models at supersonic speeds. Based on the results of the thermal fluid-solid coupling calculation, the skeleton structure of the swept wing is optimized, and the skeleton structure with 25% mass reduction and better performance is obtained.
{"title":"A Shear-Sliding Rigid-Flexible Coupled Skin Variable-Sweep Wing Design and Heat-Fluid-Structure Multifield Coupling Analysis","authors":"Hong Xiao, Hongwei Guo, Mingqi Li, Yu Zhang, Rongqiang Liu, Jianguo Tao","doi":"10.1155/2023/7078091","DOIUrl":"https://doi.org/10.1155/2023/7078091","url":null,"abstract":"The variable-sweep wing is very attractive for cross-speed domain aircraft. The shear-sliding rigid-flexible coupled skin variable-sweep wing and its associated mechanism are designed and optimized. The variable-sweep wing has smooth continuous deformation and rigid-flexible coupling features. The calculation model of the sliding skin patch segmentation strategy is established, and the aerodynamic characteristics of the two-dimensional airfoil before and after the deformation of the wing skin are analyzed. According to the deformation characteristics of sliding skin, the configuration of the associated mechanism is determined, and the kinematic characteristics of the reference points of each skin are calculated. The kinematic simulation verifies the force of the mechanism model at the joint of skin surfaces during the deformation process. Considering the aerodynamic heat at supersonic speed, the heat transfer, heat distribution, and structural thermal modes between the flow field and the skin are calculated based on the finite element method. The dynamic characteristics of the swept wing with different flight speeds and different morphologies are analyzed. The natural frequencies are found to be reduced by about 30% to 50% compared to cold models at supersonic speeds. Based on the results of the thermal fluid-solid coupling calculation, the skeleton structure of the swept wing is optimized, and the skeleton structure with 25% mass reduction and better performance is obtained.","PeriodicalId":13748,"journal":{"name":"International Journal of Aerospace Engineering","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42932514","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The automatic carrier landing process is a significant and complex due to the plant variation of carrier-based aircraft. To reasonably identify the stability interval for specific performance, an adaptive control strategy based on the guardian map approach is proposed. Prescribed performance, namely, stability margin, damping requirements, or flying quality requirements, is analytically formulated using a guardian map. The null space of guardian maps restricts the prescribed performance regarding the poles’ location. The feasible corridor of control parameters is generated based on the null space of guardian maps. Besides, a velocity-adaptive prescribed performance control method is proposed to conduct the attitude control of carrier-based aircraft. Simulation shows that the short-period mode of carrier-based aircraft will be driven from unstable to stable as the velocity decreases. Moreover, simulation results demonstrate the proposed control method and indicate that the attitude loop control of carrier-based aircraft possesses more underdamped responses as the velocity decreases.
{"title":"Velocity-Adaptive Prescribed Performance Control for Carrier-Based Aircraft Based on Guardian Maps","authors":"Chenliang Li, Jizhou Lai, Boyi Chen, Yanbin Liu","doi":"10.1155/2023/5541378","DOIUrl":"https://doi.org/10.1155/2023/5541378","url":null,"abstract":"The automatic carrier landing process is a significant and complex due to the plant variation of carrier-based aircraft. To reasonably identify the stability interval for specific performance, an adaptive control strategy based on the guardian map approach is proposed. Prescribed performance, namely, stability margin, damping requirements, or flying quality requirements, is analytically formulated using a guardian map. The null space of guardian maps restricts the prescribed performance regarding the poles’ location. The feasible corridor of control parameters is generated based on the null space of guardian maps. Besides, a velocity-adaptive prescribed performance control method is proposed to conduct the attitude control of carrier-based aircraft. Simulation shows that the short-period mode of carrier-based aircraft will be driven from unstable to stable as the velocity decreases. Moreover, simulation results demonstrate the proposed control method and indicate that the attitude loop control of carrier-based aircraft possesses more underdamped responses as the velocity decreases.","PeriodicalId":13748,"journal":{"name":"International Journal of Aerospace Engineering","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49342971","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：