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Considering the strong nonlinearity of Unmanned Aerial Vehicles (UAVs) resulting from high Angle of Attack (AoA) and fast maneuvering, we present a multi-model predictive control strategy for UAV maneuvering, which has a small amount of online calculation. Firstly, we divide the maneuver envelope of UAV into several sub-regions on the basis of the gap metric theory. A novel algorithm is then developed to determine the ploytopic model for each sub-region. According to this, a Robust Model Predictive Control based on the Idea of Comprehensive optimization (ICE-RMPC) is proposed. The control law is designed offline and optimized online to reduce the computational expense. Then, the ICE-RMPC method is applied to design the controllers of sub-regions. In addition, to guarantee the stability of whole closed-loop system, a multi-model switching control strategy based on guardian maps is put forward. Finally, the tracking performance of proposed control strategy is demonstrated by an illustrative example.

An integrated approach that considers the performance limitations of tracking control systems for air-breathing hypersonic vehicles is proposed. First, a set of ascent trajectories is obtained as candidates for tracking control through a trajectory design method that considers the available acceleration. Second, the basic theory of performance limitations, which is adopted to calculate the limits on control performance through the trajectory, is integrated. The open-loop dynamics of air-breathing hypersonic vehicles is responsible for these limits on the control system. Comprehensive specifications on stability, tracking accuracy, and robustness are derived, and the flight envelope with constraints and control specifications is identified. Simulation results suggest that trajectory design should consider restrictions on control performance to obtain reliable solutions. Keywords: Bandwidth constraints, Hypersonic vehicles, Performance limitations, Robust performance, Trajectory tracking control

Aiming to the complex operation condition and strong coupling dynamic characteristics of hypersonic vehicles, this paper develops a parametric model which is suitable to the control integrated design. First, the necessities and research status of the control integrated design of hypersonic vehicles are discussed. Then, the typical hypersonic waverider shape is geometrically parametrized using the quadratic curve and class/shape function methods. After that, the forces and moments of the hypersonic vehicle are estimated based on the surface element method in combination with the engineering estimation formulas, and the nonlinear dynamic parametrization model is built. Furthermore, the analytical expressions of forces and moments are obtained by means of the sensitive analysis strategies as a result that the complicated nonlinear dynamics model is changed to the iterative design model. Finally, an illustrative example is provided to verify the feasibility of this proposed method, and the according results show that the developed parametrization model enables to meet the requirements of the control integrated design.

This paper has researched the influence on body shape design of hypersonic vehicle on flight performance and control stability. Control-oriented parametric model is established, and some important geometric parameters of the parametric model are put into the expression of aerodynamic coefficient to measure the degree of influence on performance. The results show that the length of the elevator influences the control effect and the upper angle of forebody effects on the balanced force and moment significantly. Consequently, the geometric parameters are easily determined in model design and the number of iterations between body system and control design is reduced.

The equivalent sample theory and its application in analysis of networked control system (NCS) are presented. After analyzing NCS's scheduling in master-slave mode, the characteristics of time delay and sample are summarized. Looking on master station visiting the slave station as a special sample process, the theory of equivalent sample is presented. And based on it, the stability of a kind of NCS is analyzed. The criterion to determine the upper bound of transmission delay is introduced, which guarantees the stability. Finally, an example with simulation shows the availability and usability of this analysis method.

In the light of the broad range of hypersonic flight conditions, a design method of switching control based on guardian maps is proposed to guarantee the global stability within the flight envelope. First, a linear parameter varying (LPV) model of a hypersonic vehicle is established over a range of hypersonic flight conditions. The parameters of controller are determined by pole placement technology with the target pole locations at the boundaries of the parameters variation range. Second, a new range of flight conditions that ensures system stability with current controller is analyzed based on guardian maps. The execution of the iterative process is used to determinate the set of controller parameters overall the flight envelope with initial target pole locations. By switching controller parameters the closed-loop performance is guaranteed over the entire flight envelope. The simulation shows that the proposed design method has the ability to ensure the global stability over the flight envelope, and achieving good tracking performance.

The Flush Airdata Sensing (FADS) system and its pressure model are presented briefly. The improved algorithm for calculating the impact pressure, static pressure and modifying coefficient are studied. First, the non-linear equations are simplified using Moore-Penrose inverse. Then the impact pressure and static pressure are computed with the improved iteration and BP neural network. Both the two improved algorithms meet the requirements of the flush airdata sensing system on precision, reliability and speed. BP neural network has great advantages on real-time requirements, for it needs only 5% time to reach the required precision comparing to the original algorithm.