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For aerospace vehicles with uncertainty, strong nonlinearity, and high-performance requirements, the model predictive control (MPC) method has attracted many researchers' attention with its unique advantages. Although this method has a good effect, it is computationally expensive, especially for the nonlinear MPC. In addition, it cannot guarantee the stability performance requirements and limited flexibility in dealing with large initial errors. To overcome these limitations, this article is implemented to obtain a control scheme that can handle uncertainty, initial deviation, and has less online calculation. To ensure the stability requirements, the guardian maps (GM) theory is combined with multimodel predictive control, and a switching rule based on GM is proposed. Then, fully considering the characteristics of linear matrix inequalities used, the idea of "offline design and online optimization" is adopted to solve the control law, which reduces the burden of online computing. Furthermore, in the case of large initial errors, a transient trajectory design method is established to reconstruct the trajectory online, and to modify the tracking command. Simulation results verify the effectiveness of the designed control scheme. [ABSTRACT FROM AUTHOR]

Overall design in many air-breathing hypersonic vehicles (AHSVs) uses the integrated airframe/scramjet configuration formed with elongated fuselage and light structure, resulting in intricate aerodynamic–propulsive-elastic couplings. In this paper, a high-fidelity flexible AHSV dynamic modeling procedure is proposed at first, which consists of three main parts: i) panel method based aerodynamic modeling; ii) scramjet modeling; iii) finite-element-method (FEM) based aeroelastic modeling. Unsteady and viscous effects are estimated through linear piston theory and Eckert's reference temperature method, respectively. Additional models for shock interaction, ram-to-scram transition, and finite rate chemistry reaction are also included. To overcome the intractability of physics-based model, the Morris method is applied to identify the main influence factors during surrogate modeling. Then to investigate the flexible mode effect on the stability boundary, the principle of Null-controllability region (NCR) is employed, under control input saturation and bandwidth constraints. The X-43A like air-breathing hypersonic vehicle operating at cruise condition is studied for verification purpose, and the Monte-Carlo simulation results demonstrate the effectiveness of the proposed dynamic modeling and performance limitation analysis approach. [ABSTRACT FROM AUTHOR]

The application of an airplane to explore Mars may become an important research aera due to some distinctive advantages such as the large detection range and good maneuvering characteristics. Also, the resulting works have the strong forward-looking and driving actions which are helpful for mankind to realize the intergrated design dreams concerning aerospace technologies. This paper discusses the complex modeling and sliding control law design issues for Mars airplane. First, the particular features with regard to atmospheric environment on Mars are considered to explain the Martian flight principles as well as to provide the faced new challeges in comparison to the conventional airpalne on Earth. Afterwards, the mathematical model of Mars airplane is established using the isolation methods, and based on this built model the dynamic characteratics are analyzed under the Martian atmospheric environment in order to indicate the importance of the control actions. Furthermore, the sliding control law is proposed to meet the anticipated demands including robust stability and adaptive track response. Finally, a simulation example is given to verify the effectiveness of the proposed modeling and control methods, and the according works will also provide the good theoretical reserve and technical support to independently develop Mars airplane in the future. [ABSTRACT FROM AUTHOR]

This study investigates the optimal design problems for the hypersonic morphing vehicle. The correlations among the shock wave variation, propulsive performance, and control effect are discussed. The inversion design methods are applied to calculate the aerodynamic forces and moments of the hypersonic morphing vehicle based on the theories of the hypersonic computational mechanics. Then, the hypersonic morphing vehicle model is built, and the optimal performance indexes reflecting the waverider flight characteristics considering the appropriate flight conditions and the initial model parameters are presented. Furthermore, the variable metric algorithm is used to iteratively optimize the performance function. The optimum model parameters for the hypersonic morphing vehicle are then obtained with the control requirements. Finally, the effectiveness of the optimal design methods is verified by simulation. In general, the designs are preliminarily completed, along with the synthesis of the shape, aerodynamic force, propulsion, and the control action. We believe that this study provides helpful information on hypersonic morphing vehicles to guide future research. [ABSTRACT FROM PUBLISHER]