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Cargo airships: International Competition

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Journal of Transportation Technologies 2014年第3期4卷 187-195页

作者： Barry E. Prentice Robert Knotts Airship Association London UK I.H. Asper School of Business University of Manitoba Winnipeg Canada

The advance of transportation technology depends on science and economics. During the 1930s, airships and airplanes competed head-to-head for the Atlantic passenger market. When World War 2 broke out, everything changed. Over the next five years, the combined combatants built over half of a million military airplanes. By the end of the war, four-engine, high-altitude bombers and jet engines were developed. Further investment in airplane technology was stimulated by the Cold War. All this public investment was adapted to civilian passenger jet airplanes. By 1980, dedicated jet airplanes were in use as cargo carriers. Despite the growth of the cargojet market over the past three decades, rising fuel costs and environmental concerns are changing the economics of airships and airplanes again. Investment in large cargo airships is returning. Much of the technology developed for fixed-wing aircraft can be applied to cargo airships. New materials, better engines, control systems and engineering eliminate the need for large ground crews and improve airship reliability and safety. However, two fundamental design issues have yet to be resolved: structural integrity and buoyancy control. A worldwide competition is underway on three continents to develop the dominant design for a cargo airship. This paper examines the alternative design approaches and presents the status of the international competition.

关键词： Cargo airships Dominant Design World Developments

Analysis and Simulation of the Stratospheric Quasi-zero Wind Layer over Korla, Xinjiang Province, China

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Advances in Atmospheric Sciences 2019年第10期36卷 1143-1155页

作者： Rui YANG Lingkun RAN Yuli ZHANG Yi LIU Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Guangzhou Meteorological Observatory Guangzhou 511430 China University of Chinese Academy of Sciences Beijing 100049 China

The stratospheric quasi-zero wind layer (QZWL) is a transition region with low zonal wind speeds in the lower stratosphere at an altitude of ~20 km. The zonal wind direction above the QZWL layer is opposite to that below the QZWL layer and the north –south wind component is small. The atmospheric wind field near the stratospheric QZWL is an important factor affecting the flight altitude and dynamic control of stratospheric airships. It is therefore necessary to study the stratospheric QZWL to provide better environmental information for these aircraft. High-resolution radiosonde data were used to analyze the characteristics of the stratospheric QZWL over Korla, Xinjiang Province, China. A weak wind layer in which the wind direction suddenly reversed from westerly to easterly was observed at ~20 km in the lower stratosphere, characteristic of the stratospheric QZWL. The Weather Research and Forecasting model was used to simulate the profiles of the horizontal wind speed and direction over Korla. The forcing effect of each diagnostic term in the equation on the zonal wind speed was analyzed. The results showed that the advection term was the dominant factor forcing the zonal wind speed. The wave term had a secondary forcing role, although the forcing effect of the wave term on the zonal wind speed was significant in some regions.

关键词： numerical simulation radiosonde stratospheric airships stratospheric quasi-zero wind layer

Continuous Sliding Mode Controller with Disturbance Observer for Hypersonic Vehicles

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IEEE/CAA Journal of Automatica Sinica 2015年第1期2卷 45-55页

作者： Chaoxu Mu Qun Zong Bailing Tian Wei Xu the Department of Electrical Engineering and Automation Tianjin University the School of Electrical and Electronic Engineering Huazhong University of Science and Technology

In this paper, a continuous sliding mode controller with disturbance observer is proposed for the tracking control of hypersonic vehicles to suppress the chattering. The finite time disturbance observer is involved to make that the continuous sliding mode controller has the property of disturbance rejection. Due to continuous terms replacing the discontinuous term of traditional sliding mode control, switching modes of velocity and altitude firstly arrive at small regions with respect to disturbance observation errors. Switching modes keep zero and velocity and altitude asymptotically converge to their reference commands after disturbance observation errors disappear. Simulation results have proved the proposed method can guarantee the tracking of velocity and altitude with continuous sliding mode control laws, and also has the fast convergence rate and robustness. © 2014 Chinese Association of Automation.

关键词： airships Altitude control Controllers Disturbance rejection Errors Hypersonic aerodynamics Hypersonic vehicles Robustness (control systems) Vehicles

Trajectory Tracking of Vertical Take-off and Landing Unmanned Aerial Vehicles Based on Disturbance Rejection Control

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IEEE/CAA Journal of Automatica Sinica 2015年第1期2卷 65-73页

作者： Lu Wang Jianbo Su the Department of Automation Key Laboratory of System Control and Information Processing Ministry of Education Shanghai Jiao Tong University

We investigate the trajectory tracking problem of vertical take-off and landing (VTOL) unmanned aerial vehicles (UAV), and propose a practical disturbance rejection control strategy. Firstly, the nonlinear error model is established completely by the modified Rodrigues parameters, while considering dynamics of the servo actuators. Then, a hierarchical control scheme is applied to design the translational and rotational controllers based on the time-scale property of each subsystem, respectively. And the linear extended state observer and auxiliary observer are used to deal with the uncertainties and saturation. At last, global stability of the closed-loop system is analyzed based on the singular perturbation theory. Simulation results show the effectiveness of the proposed control strategy. © 2014 Chinese Association of Automation.

关键词： Aircraft control airships Closed loop control systems Closed loop systems Disturbance rejection Landing Perturbation techniques State estimation Takeoff Trajectories Unmanned vehicles Vehicles

Decoupling Trajectory Tracking for Gliding Reentry Vehicles

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IEEE/CAA Journal of Automatica Sinica 2015年第1期2卷 115-120页

作者： Zixuan Liang Zhang Ren Xingyue Shao the Science and Technology on Aircraft Control Laboratory Beihang University

A decoupling trajectory tracking method for gliding reentry vehicles is presented to improve the reliability of the guidance system. Function relations between state variables and control variables are analyzed. To reduce the coupling between control channels, the multiple-input multiple-output (MIMO) tracking system is separated into a series of two single-input single-output (SISO) subsystems. Tracking laws for both velocity and altitude are designed based on the sliding mode control (SMC). The decoupling approach is verified by the Monte Carlo simulations, and compared with the linear quadratic regulator (LQR) approach in some specific conditions. Simulation results indicate that the decoupling approach owns a fast convergence speed and a strong anti-interference ability in the trajectory tracking. © 2014 Chinese Association of Automation.

关键词： airships Altitude control Channel estimation Hypersonic vehicles Intelligent systems MIMO systems Monte Carlo methods Sliding mode control Telecommunication repeaters Trajectories Vehicles

Adaptive Sliding Mode Control for Re-entry Attitude of Near Space Hypersonic Vehicle Based on Backstepping Design

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IEEE/CAA Journal of Automatica Sinica 2015年第1期2卷 94-101页

作者： Jingmei Zhang Changyin Sun Ruimin Zhang Chengshan Qian the Flight Control Research Center Key Laboratory of Measurement and Control of Complex Systems of Engineering Ministry of Education School of Automation Southeast University the College of Information and Control Nanjing University of Information Science & Technology

Combining sliding mode control method with radial basis function neural network (RBFNN), this paper proposes a robust adaptive control scheme based on backstepping design for re-entry attitude tracking control of near space hypersonic vehicle (NSHV) in the presence of parameter variations and external disturbances. In the attitude angle loop, a robust adaptive virtual control law is designed by using the adaptive method to estimate the unknown upper bound of the compound uncertainties. In the angular velocity loop, an adaptive sliding mode control law is designed to suppress the effect of parameter variations and external disturbances. The main benefit of the sliding mode control is robustness to parameter variations and external disturbances. To further improve the control performance, RBFNNs are introduced to approximate the compound uncertainties in the attitude angle loop and angular velocity loop, respectively. Based on Lyapunov stability theory, the tracking errors are shown to be asymptotically stable. Simulation results show that the proposed control system attains a satisfied control performance and is robust against parameter variations and external disturbances. © 2014 Chinese Association of Automation.

关键词： airships Angular velocity Attitude control Backstepping Control theory Design Functions Hypersonic aerodynamics Hypersonic vehicles Navigation Radial basis function networks Sliding mode control Uncertainty analysis Vehicles

A Predator-prey Particle Swarm Optimization Approach to Multiple UCAV Air Combat Modeled by Dynamic Game Theory

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IEEE/CAA Journal of Automatica Sinica 2015年第1期2卷 11-18页

作者： Haibin Duan Pei Li Yaxiang Yu the Science and Technology on Aircraft Control Laboratory School of Automation Science and Electrical EngineeringBeihang University (BUAA)

Dynamic game theory has received considerable attention as a promising technique for formulating control actions for agents in an extended complex enterprise that involves an adversary. At each decision making step, each side seeks the best scheme with the purpose of maximizing its own objective function. In this paper, a game theoretic approach based on predatorprey particle swarm optimization (PP-PSO) is presented, and the dynamic task assignment problem for multiple unmanned combat aerial vehicles (UCAVs) in military operation is decomposed and modeled as a two-player game at each decision stage. The optimal assignment scheme of each stage is regarded as a mixed Nash equilibrium, which can be solved by using the PP-PSO. The effectiveness of our proposed methodology is verified by a typical example of an air military operation that involves two opposing forces: the attacking force Red and the defense force Blue. © 2014 Chinese Association of Automation.

关键词： Aircraft control airships Combinatorial optimization Computation theory Decision making Military operations Military vehicles Particle swarm optimization (PSO)

Robust Tracking Control of Uncertain MIMO Nonlinear Systems with Application to UAVs

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IEEE/CAA Journal of Automatica Sinica 2015年第1期2卷 25-32页

作者： Yanlong Zhou Mou Chen Changsheng Jiang the College of Automation Engineering Nanjing University of Aeronautics and Astronautics

In this paper, we consider the robust adaptive tracking control of uncertain multi-input and multi-output (MIMO) nonlinear systems with input saturation and unknown external disturbance. The nonlinear disturbance observer (NDO) is employed to tackle the system uncertainty as well as the external disturbance. To handle the input saturation, an auxiliary system is constructed as a saturation compensator. By using the backstepping technique and the dynamic surface method, a robust adaptive tracking control scheme is developed. The closed-loop system is proved to be uniformly ultimately bounded thorough Lyapunov stability analysis. Simulation results with application to an unmanned aerial vehicle (UAV) demonstrate the effectiveness of the proposed robust control scheme. © 2014 Chinese Association of Automation.

关键词： Aircraft control airships Backstepping Closed loop control systems Closed loop systems Nonlinear systems Robust control Unmanned aerial vehicles (UAV) Unmanned vehicles