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In this paper, on the basis of sliding mode control theory, a new integral tangent adaptive fuzzy sliding mode control for aircraft engine was proposed. Based on the uncertainty model of aircraft engine, a hyperbolic tangent integral sliding surface was constructed at first, and it effectively overcome the problem of integral saturation effect which was often occur in the traditional integral sliding...
Considering the Insect-like flapping-wing micro aerial vehicle, this paper has analyzed the composite of quasi-steady aerodynamics. That process has associated with the affection due to addition quality produced by wake capture. With introducing rotate circulation. This paper has calculated the lift, drag force, and pitch torque which take part on the wings' surfaces. Ignoring the wings' quality,...
In this paper, an improved cascade second-order sliding mode (SOSM) methodology for a polymer electrolyte membrane (PEM) fuel cell air supply system is proposed. Based on the simplified six-order nonlinear model, the control objective oxygen excess ratio is achieved by using SOSM algorithm. Besides, parametric uncertainty and noise are presented in the dynamic fuel cell model. The modified two stage...
To apply the smart wolf pack algorithm to solve the uncertain bilevel knapsack problem effectively, a binary smart wolf pack algorithm is designed. Firstly, the paper proposes an uncertain bilevel knapsack problem model by introducing uncertainty theory to the traditional bilevel knapsack problem model. Secondly, to solve the model of uncertain bilevel knapsack problem by the algorithm directly, we...
In this paper, we develop a data-driven model of a model-sized aircraft using system identification (SysID) techniques. The emphasis is placed on multiple short data records that are used in obtaining an initial model of the system. The records are “short” with respect to the length of a “typical” identification experiment and are necessary because of the unstable nature of the open-loop system. Owing...
Three-degree-of-freedom trajectory tracking of the stratospheric airship is investigated. With a simplified planar dynamic model, an adaptive backstepping sliding mode controller is designed to keep the airship to globally asymptotically track a desired trajectory. Lyapunov functions are used to ensure the tracking performance when model parametric uncertainty and external disturbances exist. Simulation...
Nonlinear dynamic inversion (NDI) has been applied to the control law design of UAVs for many years mainly due to its good robustness. However, it has a weakness of relying on accurate model of the plant greatly, which restrains its application since UAVs are easy to be influenced by persistent disturbances such as model uncertainties, winds and gusts; thus, development of accurate model for attitude...
The optimization of spare parts inventory for equipment support system is becoming a dominant support strategy, especially in the defense industry. Tremendous researches have been made to achieve optimal support performance of the supply system. However, the lack of statistical data brings limitations to these optimization models which are grounded on probability theory. And, the spare parts inventory...
In this paper, a robust trajectory tracking control for the underactuated quadrotor unmanned aerial vehicle (UAV) based on extended state observer(ESO) is proposed. In the presence of external disturbances and inner model parameter uncertainty, it guaranteed that the position and yaw angle could track the reference signal speedily and smoothly. According to the strict feedback architecture of the...
This paper studies the attitude control problem for the longitudinal motion of a hypersonic aircraft model containing 28 inertial and aerodynamic uncertain parameters given by NASA Langley Research Center. To handle the nonlinear dynamics and uncertain parameters, ADRC for the unobservable and unmatched disturbance is designed. Besides, the properties of the closed-loop system is discussed in two...
In view of the mars reentry problem under external disturbance, this paper presents a guidance algorithm based on drag tracking. First of all, the reference drag is calculated based on the reentry model and the reference trajectory. Secondly, estimated disturbance via the sliding mode observer, this paper improve the accuracy of the controller parameters and increase the anti-disturbance capability...
A robust entry guidance law with finite time convergence is designed for drag-tracking in this paper. The bank angle is regarded as the control variable. First, a robust sliding mode control (SMC) method, which can guarantee the finite time convergence, is proposed for a class of nonlinear systems with uncertainties and disturbances. Then, after the drag dynamics is given, the finite time guidance...
This paper develops two robust adaptive controllers for UAVs. The first controller is the robust adaptive PID based on fuzzy logic. The other is the intelligent flight controller based on ANFIS. The simulation results exhibit the robustness of the developed controllers. Likewise, the results present that the intelligent flight controller based on ANFIS produces better robustness performance than robust...
This paper examines the potential impacts of remote sensing, hyperspectral target detection from a physics-based modeling point of view. Often (atmospherically compensated) data is simply handed off to algorithm developers with the assumption that the data they are given accurately represents what transpired at the time of collection. In this paper, we discuss the various steps involved in processing...
In this study, the automatic reflectance-based method is used to vicarious radiometrically calibrate the satellite optical sensors using the desert target located in the Baotou site in China. The ground reflected radiance of the desert target were collected automatically using an automatic observation system. The reflectance of the desert target was calculated with the radiance collected with the...
This paper presents a detailed study on the performance, generality and robustness of proportional method. A probabilistic model was proposed to predict the number of iterations needed for air balancing under different sensor uncertainties. This model was later validated by simulations in a duct system with 12 nodes and 20 branches. And the correlation between the efficiency of proportional method...
Uncertainty takes different forms in air transportation systems. One form is demand uncertainty which is mainly due to the root cause of aircraft departing in deviated time slots. This can lead to severe consequences, including capacity violation in air routes. The current Air Traffic Flow Management (ATFM) literature does not consider demand uncertainty in flight scheduling. However, in reality,...
The high-accuracy trajectory tracking pneumatic position servo system proposed in this paper mainly consists of a cylinder which is controlled by a proportional directional control value. Due to there exist large extent of parametric uncertainties and severe uncertain nonlinearities in the pneumatic system, an adaptive robust control strategy was constructed, which employs on-line recursive least...
In this paper, we implement a robust model reference adaptive control (MRAC) as part of an ongoing effort to demonstrate practical application of a nonlinear control system to the pitch-attitude hold of an aircraft model. We show that MRAC can improve transient performance and compensate changes in the performance characteristics of the aircraft mid-flight by evaluating an example where a change in...
Although for the general public marine oil pollution happens when an oil tanker sinks in the ocean or an accident occurs in an oil platform, most of the oil entering the world ocean does it along less obvious paths. This research work focus on operational spills. It provides a first indication of the uncertainty associated to backtracking simulations using solutions from several operational models...
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