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In order to improve the safety of formation flight, a method using wingtip normal blowing is proposed to weaken the influence of the wake generated by the leading aircraft. Numerical simulation methods are employed to analyze the aerodynamic characteristics of the following aircraft affected by the wake of the leading aircraft during different formation positions. Additionally, numerical simulation is conducted on the wingtip normal blowing. The simulation results indicate that during formation flight, the following aircraft experiences significant disturbance torque when transiting laterally through the vortex area of the leading aircraft, which increases the difficulty of rudder manipulation and aircraft control, posing a serious threat to the safety of the following aircraft. After introducing wingtip normal blowing, the wingtip vortex of the following aircraft is weakened, and the lift-to-drag ratio increases with the augmentation of the blowing momentum coefficient. Subsequently, a formation flight control system with wingtip normal blowing is established in Simulink for simulation. The simulation results demonstrate that the proposed wingtip normal blowing mitigates the influence of the wake from the leading aircraft, reducing both the lateral position and velocity deviations of the following aircraft as it traverses the vortex area of the leading aircraft. Concurrently, the aileron deflection of the following aircraft is significantly decreased, thereby improving the safety of the following aircraft. [ABSTRACT FROM AUTHOR]

Flight control system is typical safety critical system, and the reliability of flight control system plays an important role in ensuring the safe operation of aircraft. Traditional reliability analysis methods have a heavy reliance on the experience of analysts, which makes it easy for inconsistencies between reliability models and design models. The fault propagation behavior of the system is thoroughly described by the Architecture Analysis Design Language（AADL）and stochastic Petri nets（SPN）, and a method for model-based reliability analysis is proposed. The nominal model and error model of a lateral fly-by-wire flight control system are constructed using AADL. A method for extracting error propagation information from the AADL model is proposed, and the SPN model described the fault propagation behavior of the system is automatically generated by extracting the information of AADL model. Based on the SPN model, Monte Carlo simulation is used to evaluate the reliability of the lateral fly-by-wire flight control system, compared with the fault tree analysis method, the error is less than 0.018%, which can be neglected in practice. Through the method of this study, the reliability model is automatically generated by the AADL model, which ensures the consistency between the reliability model and the design model and avoids reliance on the experience of designers.

Model-based systems engineering (MBSE) has been widely used in complex system design. A multi-level progressive architecture design process based on MBSE is proposed by constructing the relationship between function, behavior and structure. Subsequently, guided by the demand for altitude control, an example modeling of the civil aircraft flight control system is conducted. The results indicate the multi-level progressive architecture design of civil aircraft flight control system architecture based on MBSE leverages the advantages of reusable digital models, ensuring a close integration of requirements with functional, logical, and physical architecture. Meanwhile, the method improves the traceability of system design and provides an architectural reference for subsequent domain level model design. [ABSTRACT FROM AUTHOR]

Copyright of Control Theory & Applications / Kongzhi Lilun Yu Yinyong is the property of Editorial Department of Control Theory & Applications and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Automatic flight control system （AFCS） is one of the most important safety‑critical systems in modern aircraft, and flight guidance control system （FGCS） is an important part of it. There are dozens of flight modes in FGCS, and its mode conversion logic is very complex, which is prone to pattern confusion and other problems in the conversion of various modes, making it difficult to verify their safety and correctness. However, formal modeling and verification of safety‑critical systems can improve the correctness and safety of the system by using formal methods in computer science. This paper takes the automatic flight mode conversion logic of typical FGCS as the research object, uses the software tool ART （Avionics requirement tool） independently developed by the author team to carry out formal modeling and verification, and compares the verification ability and efficiency with the Design Verifier tool in Matlab/Simulink. The case study results show that it is feasible to model and verify the automatic flight mode conversion logic of FGCS using formal methods. Meanwhile, our software platform has more complete verification capability and better verification efficiency. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Shanghai Jiao Tong University (1006-2467) is the property of Journal of Shanghai Jiao Tong University Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The hardware and software of the flight control system of tandem unmanned helicopter were designed using embedded design technology. For the hardware of the flight control system, STM32 H750 VBT6 was used as the main control chip of the system, and the multi-sensor attitude measurement hardware system was constructed using 6-axis motion processing sensor LSM6 DSR and three-axis magnetometer LIS2 MDL. The timer on the main control chip was used to receive remote control input signal, output PWM motor control signal and steering gear control signal. For the flight control system software, the quaternion complementary filtering method was used to fuse the acceleration and angular velocity measured by the inertial navigation module and the three-axis magnetic field intensity measured by the magnetometer, and the flight attitude of the UAV was calculated. Cascade control strategy was adopted in the control strategy. The attitude angle of the UAV was controlled by the outer loop controls, and the attitude angular velocity of the UAV was controlled by the inner loop controls to achieve rapid and accurate control of the UAV attitude. The results show that the software and hardware of the flight control system of tandem unmanned helicopter are realized, and the expected results are achieved according to the flight test verification. [ABSTRACT FROM AUTHOR]

Copyright of Systems Engineering & Electronics is the property of Journal of Systems Engineering & Electronics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Computer Engineering & Applications is the property of Beijing Journal of Computer Engineering & Applications Journal Co Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Assigning development assurance levels for items/functions and conducting corresponding development assurance activities can minimize the possibility of errors in the development process. The development assurance levels of the items/functions consisting of the system are taken as decision variables, the assignment principle of development assurance levels and the probability requirement of the top failure conditions are taken as constraints, and the minimization of the development cost is taken as the optimizing objective, the model of the development assurance level assignment is established. Taking the vector composed of the development assurance levels of all items/functions as the individual chromosome, a method of solving the model is proposed based on the a genetic algorithm and particle swarm optimization (GA-PSO) hybrid algorithm. Finally, an application instance is given based on a hypothetical air-borne system and a certain fly-by-wire flight control system. The results show that the proposed method can reduce the dependence on designers' experiences or skills effectively, and has higher accuracy and efficiency compared with other algorithms. [ABSTRACT FROM AUTHOR]

Copyright of Control Theory & Applications / Kongzhi Lilun Yu Yinyong is the property of Editorial Department of Control Theory & Applications and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Systems Engineering & Electronics is the property of Journal of Systems Engineering & Electronics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Systems Engineering & Electronics is the property of Journal of Systems Engineering & Electronics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Systems Engineering & Electronics is the property of Journal of Systems Engineering & Electronics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Control Theory & Applications / Kongzhi Lilun Yu Yinyong is the property of Editorial Department of Control Theory & Applications and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Control Theory & Applications / Kongzhi Lilun Yu Yinyong is the property of Editorial Department of Control Theory & Applications and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In view of the high requirements of attitude control in flight control system and the various unknown disturbances and parameter uncertainties in flight, a fuzzy parameter optimization of active disturbance rejection control strategy was proposed to achieve the high performance of attitude control for tandem UA V. The transition process was arranged to reduce overshoot and improve response speed, and the extended state observer was designed to deal with unknown disturbances and parameter uncertainties. To improve the dynamic performance of control system, the fuzzy control was used to realize the online adjustment of the gain of nonlinear feedback control law. The simulation results show that compared with the conventional PID and fuzzy PID control, the fuzzy parameter optimization of active disturbance rejection control strategy can suppress the disturbance quickly and effectively with high control accuracy and strong robustness. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Control Theory & Applications / Kongzhi Lilun Yu Yinyong is the property of Editorial Department of Control Theory & Applications and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Control Theory & Applications / Kongzhi Lilun Yu Yinyong is the property of Editorial Department of Control Theory & Applications and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aiming at the problem of low intellectualization of program controlled unmanned aerial vehicle （UAV），intelligent correction method for flight control system based on online simulation system is proposed. Online state monitoring and anlysis，real⁃time updating of simulation model and other technologies are used. UAV online simulation system is designed to auxiliary controll UAV's track correction and speed correction. Intelligence of UAV flight control is improved further. Through UAV mathematical model simulation system and simulation and test system of flight control system hardware in loop，experimental verification is conducted. The effective combination of intelligent correction technology and man in the loop control method is realized. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The spherical omnidirectional moving self-balancing robot model originates from the inverted pendulum and is a typical multivariable, nonlinear, high order, strongly coupled and statically unstable system. In this paper, the traditional flight control system is improved, and a cascade PID control system design method being suitable for spherical omnidirectional mobile self-balancing robot is proposed to realize the control tasks of fixed-point upright and omnidirectional movement of the robot. Through the analysis of the IASMP model of the robot, the internal motor control parameters of the robot are determined. The dynamic model of the robot is established by using the SimMechanics toolbox. The simulation model of the controller is designed in Simulink, and the control algorithm is simulated and verified. Finally, the controller is designed according to the simulation model, and the physical verification is carried out on the Ballbot robot. The results show that the Euler angle variation in each direction of the robot is controlled within 3°, and the actual heading deviation of the robot during the omnidirectional movement is within 2°. And it can complete the circular motion autonomously. The simulation and physical verification results prove the rationality and effectiveness of the robot' s upright control and motion control, and show strong robustness. [ABSTRACT FROM AUTHOR]

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Computer Measurement & Control is the property of Magazine Agency of Computer Measurement & Control and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Farmland information acquisition is the basis of precision agriculture. Multi-rotor unmanned aerial vehicle (UAV) can obtain farmland information quickly, efficiently and accurately. But as an under actuated system, the flight stability of multi-rotor UAV is susceptible to natural wind, electromagnetic interference and the near surface factors in farmland environment. The flight stability control method is important in multi-rotor UAV flight and affects qualified information acquisition. In this paper, multi-rotor UAV was adopted as research object and its body coordinate system and navigation coordinate system were established. Based on its motion analysis, changing 4 motors speed can realize multi-rotor UAV attitude regulation. The multi-rotor UAV platform consisted of brushless motors, electric speed controllers and composite-fiber fabric propellers. The flight control system was designed based on STM32F407 as master controller, MPU6050 as motion sensor integrated with 3-axis accelerometer and 3-axis gyroscope, AK8975 as 3-axis magnetometer. The attitude of multi-rotor UAV was measured and computed by the sensors above. The timers in the controller were used for capturing the input signals from remote control and generating PWM output signals for motors control. Multiple tasks including attitude measurement remote control input process, attitude stabilization management and motors control output were scheduled by task scheduling method in the control system. The mathematical model of multi-rotor UAV attitude control was established. Through matrix calculation, the multi-rotor UAV attitude angle and throttle control inputs were mapped to each motors speed control. Then the control principle applied in this study was explained. The double closed-loop proportional integral differential (PID) control strategy with angular velocity as the inner feedback loop and angle as the outer feedback loop was proposed. A multi-rotor UAV experimental platform was built to gain the proper PID control parameters of inner and outer control loops through engineer debugging method. The double closed loop PID control method was further improved by expert control strategy. The expert control rules included throttle input ratio definition, angle and angular velocity integration limitation, angle differential control parameter variation, input and output control limitation. By introducing the expert rules, the control parameters were diverse to be adapted to the multi-rotor UAV attitude change. Anti-interference tests and step response tests were taken to testify the designed control system on the experimental platform. In the traditional PID control, when interference angle increased, the rise time and the adjustment time of the system increased. But under the effect of variable derivative, when the interference angle became large, the rise time did not increase. The rise time of the system was less than 0.27 s. When the system was subjected to 30° interference angle, the adjustment times for roll angle, pitch angle and yaw angle restored to balance were less than 3.4 and 4 s respectively. In the step response tests, rise time, maximum overshoot, adjustment time and oscillation frequency of the system were recorded. According to the statistics, the maximum adjustment times for roll angle, pitch angle and yaw angle were less than 2.2 s and 3.4 s respectively. It proved that the double closed-loop PID expert control strategy adopted in this paper made the multi-rotor UAV have quick response, small fluctuation and stable control performance. Rice breeding base was chosen as outdoor farmland circumstance to test the multi-rotor UAV attitude control performance. Because the multi-rotor UAV flight cannot avoid wind interference in outdoor, higher inner loop proportion value, outer loop proportion and differential value in roll and pitch control made the multi-rotor UAV more agile, responsive to control input and stronger resistance to wind disturbance. I [ABSTRACT FROM AUTHOR]

In order to cope with the problem of rain attenuation of relay satellites in manned space flight mission, this paper analyzes the rain attenuation performances of the three relay satellites which are involved in Tianlian series and operate in Ka band. Then influences of rain attenuation of relay satellites on manned space flight mission are discussed. Considering the environmental conditions, the objective constraints and the characteristics of China manned space flight mission, this paper proposes an implementation plan of flight control to deal with the rain attenuation of relay satellites in hope of providing reference for future manned space flight missions. [ABSTRACT FROM AUTHOR]

The aircraft model shows obvious time-varying characteristic due to the uncertainty of aerodynamic parameters. The fault diagnosis of the flight control systems is a difficult issue. A sensor fault estimation approach based on aerodynamic parameter identification and iterative learning is proposed by taking the longitudinal motion model of some unmanned aerial vehicle as the study subject. The augmented cubature Kaiman filter ( ACKF) is used for the aerodynamic parameter estimation so that the system model can be identified online. Once a fault comes up, the currently identified aerodynamic parameters are applied to system modeling in the local flight envelope, and a fault estimator is constructed using the iterative learning algorithm. Furthermore, a novel iterative learning algorithm based on the essence of extended state observer (ESO) is designed to improve the fault estimation speed. The fault simulation experiments are conducted to verify the feasibility and effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

An improved discrete wavelet-optimization method-based extreme learning machine (OMELM) algorithm is presented for the fault diagnosis of flight control system in tiltrotor aircraft. An adaptive heuristic wavelet denoising method is used to denoise the sampled signal. Feature vector of each layer is extracted using Parseval energy after the discrete wavelet decomposition of fault signal. The energy feature is normalized as the improved OMELM network input, and then the actuator fault models is classified using the improved OMELM network. Finally, an XV-15 tiltrotor aircraft mode is validated by simulation. The results show that the method has a higher average recognition rate, and needs a short diagnosis time. [ABSTRACT FROM AUTHOR]

Control load system is the human-felt system that provides operating force for pilots under the different environment. According to the flight control system's principle, the simulation means of the flight control system in flight simulator was presented, a digital electric control loading system was developed. First the paper introduces the working principle and the structure of the system, then establishes the mathematical model of column power, finally researches hardware and software of the control load system and designs the machine interface. This system has realized the simulation of the flight control system, and it has been successfully applied to flight simulator prototype system. The design of its components model can meet the general purpose of the control load system, and flexible applicability that the approach is fit for various simulation objects and control load features in different work pattern. For motion simulation, scenario simulation and other related to the displacement and force feedback simulation field also have certain reference significance. [ABSTRACT FROM AUTHOR]

To deal with the stability and stabilization problem of model parameter variation and the large-span maneuver flight of hypersonic vehicles, a robust stabilization control method was presented using switched polytopic systems. The dynamic variables of vehicle envelope were firstly divided into switched polytopic systems, and then the stability analysis was proved by employing switching parameter-dependent Lyapunov functions and the average dwell time method. Finally, the control synthesis was deduced for asymptotical stability of the aircraft dynamics within the envelope. Simulation results demonstrate that the control scheme qualifies satisfactory response and provides satisfactory command tracking, and the proposed method avoids the state jumping in traditional switching controllers and it is with low analysis and design conservation. [ABSTRACT FROM AUTHOR]

A multiple fault detection and diagnosis strategy of non-stationary random signals is presented for automatic shift control system (ASCS), which is based on the redundancy relationship between signals under the steady-state condition. The design principles of fault diagnosis strategy are put forward based on the characteristics of ASCS non-stationary random signals and the redundancy relationship between them. These principles, including credibility principle, fault compatible principle and probability principle, are the design guidelines of fault diagnosis strategy. According to the accuracy and efficiency of fault diagnosis results, the results are divided into three types. Then the fault detection and diagnosis strategy of non-stationary random signals is put forward on the basis of prior knowledge under the steady state condition of ASCS, which can realize the single fault or multiple fault diagnosis of engine speed, transmission input speed, vehicle speed and gear signal. Man-made fault is injected through the real vehicle test process to detect the integrity and validity of fault diagnosis strategy. The car data and test results show that the method is effective and practical. [ABSTRACT FROM AUTHOR]

The application of quantitative feedback theory (QFT) to design the flight control system combined with active disturbance rejection control (ADRC) algorithm for some missile is studied in this paper. From the results of simulation, the robustness analysis and the comparison of the ADRC and the PID algorithm, it could be concluded that the designed control system has good responses and robustness with satisfactory control performance. The output response overshoot of ADRC is less than PID control, but the rapidity is slightly worse than PID control. The ADRC algorithm to design the height keep loop of the missile longitudinal control system can get good tracking performance. The vertical speed tracking has hardly any overshoot, which shows good dynamic performance and steady state performance. [ABSTRACT FROM AUTHOR]

The dynamic response of morphing aircraft in the wing morphing process was simulated, and the additional forces and moments induced by wing morphing were analyzed. The result would be taken as reference for flight control of morphing aircraft. Based on Newton-Euler equations, the extended motion equations suitable for morphing aircraft were developed, in which 4 additional forces and moments were added due to the wing morphing. Vortex lattice method was used to find out the aerodynamic properties of variable wing configurations. The modeling and simulation methodology was applied to M-wing aircraft, and the dynamic response of the aircraft was analyzed with the wing changes symmetrically or asymmetrically. The result shows that the aircraft was affected significantly by the additional forces and moments. [ABSTRACT FROM AUTHOR]

The flight control system of helicopter is difficult to control for their performance of high-order unstable, nonlinear, and multiple-inputs multiple-outputs (MIMO) system. The behavior of two degree-of-freedom (2-DOF) helicopter has significant cross-coupling between pitch and yaw directional motions. This study presents a control system for a 2-DOF helicopter plant which more specific presented as twin-rotor MIMO system by using fuzzy logic technique. Fuzzy logic controller (FLC) is designed by using MATLAB to improve the performance of flight control system. Thus, the designed pitch and yaw controller are tuned by adjusting the range of membership function of input variable and the number of fuzzy rules used. The designed FLC are implemented and the results of the simulation are compared with LQR controller. The proposed pitch fuzzy controller shows improvement in rise time from 0.607sec to 0.458s, settling time from 7.188s to 1.866s, and percent overshoot from 38.1% to 0% over the existing pitch LQR controller. Meanwhile, the proposed yaw fuzzy controller shows improvement in rise time from 1.361s to 0.828s, settling time from 9.120sec to 2.517 s, and percent overshoot from 23.51% to 2.86% over the existing yaw LQR controller. Hence, the simulation results show that FLC has great potential than LQR controller for the flight control system. [ABSTRACT FROM AUTHOR]

For the aircraft pitch attitude control with model uncertainties, control surface failure, and nonlinearity disturbance, an augmentation controller based on L1 adaptive is developed. The low-pass filter with an appropriate bandwidth is designed to meet the requirements of fast adaptation and ensuring uniformly bounded performance for both the system input and output signals. Considering the fact that the servo control system with amplitude constraints, this paper derives stability condition as well as performance bounds of the controller. The results show that, choosing sufficiently large adaptation rate in the absence of amplitude constraints, the performance of the closed loop system can be made arbitrarily close to the L1 reference system. And the performance can be improved by increasing the adaptation rate in the presence of amplitude constraints, but cannot be arbitrarily close to the reference system due to the control deficiency. The proposed design is applied to pitch attitude control system for an aircraft. The simulation results verify robustness to bounded uncertainty and disturbances, while avoiding input saturation. [ABSTRACT FROM AUTHOR]

To achieve the attitude control of air-breathing hypersonic vehicle, it's necessary to analyze its complex aerodynamic characteristics, and complete the control system design. Aerodynamic characteristic of air-breathing hypersonic vehicle, namely, the variations of lift coefficient, lift-drag ratio and pitch-moment coefficient with that of attack angle at different Mach numbers, is explored by the data from wind tunnel test. The longitudinal dynamic coefficients are calculated to analyze its stability. Two different control strategies are designed based on aerodynamic analysis, one is attack angle feedback control and the other is normal overload control, and their time domain and frequency domain characteristics are calculated respectively. Experiment result shows that air-breathing hypersonic vehicle not only satisfies longitudinal dynamic stability, but also demonstrates good flight control performance. [ABSTRACT FROM AUTHOR]

Near space vehicle (NSV) has rapid flight speed, big flight envelope, aerodynamic characteristics of rapid change, and complex and variable environment of flight, so fault diagnosis and fault-tolerant control technology are significant to improve its safety and reliability. By analysis of the domestic and overseas development status on fault diagnosis and fault-tolerant control technology for NSV, the NSV dynamics model and the fault types of the flight control system are firstly introduced. Then,the existing main problems and shortcomings of fault diagnosis and fault-tolerant control technology for NSV in recent years and some new results are presented. Finally, the future directions of development and challenges for NSV in the field of fault diagnosis and fault-tolerant control are predicted. [ABSTRACT FROM AUTHOR]

The complexity of aircraft system was analyzed from the engineering point of view and the concept of aircraft family was introduced to the ontology modeling of aircraft. At the same time, the fault diagnosis of aircraft control surface was also studied. First, the domain knowledge model of aircraft ontology was built by Protégé. Then the knowledge of single fault and combined faults diagnosis were listed as SWRL rules. Finally, the diagnosis result could be concluded through JESS reasoning to select the right plan of self-repairing. This method can be used to realize the modeling of complex systems and accurate selection of fault diagnosis plan. And the knowledge base of fault diagnosis can also be improved by adding new rules. [ABSTRACT FROM AUTHOR]

This paper deals with the controller design of the attitude control system of spacecraft. The sliding mode controller was proposed to avoid the influence of parameters' uncertainty and the external disturbance. The delay factor was introduced in the reaching-law to reduce the control torque required by the system, which could save on the payload of the spacecraft. The simulation results are illustrated to verify the designed controller. The effect of improving the stability of the controller is also verified by using the sign function. [ABSTRACT FROM AUTHOR]

This paper presents a dynamics modeling and control scheme for multi-spacecraft coordinated flying based on dynamical decomposition. With certain decomposition arithmetics, physically separated spacecrafts can be connected together, and multi-spacecraft coordinated flying involved in complicated motions can be decomposed into two parts, one is the group motion of multi-spacecraft flying and the other is the relative motion of spacecrafts, formation flying. The dynamics models of these two subsystems possess the similar form with that of a single spacecraft, and the formation maintenance, reconfiguration and formation transfer within a large scope can be realized by controlling one of the subsystems. Tracking control laws for group system and formation system are also designed, and their stability is proved by Lyapunov theorem. Simulation results validate the effectiveness of the decomposition arithmetics and the control scheme. [ABSTRACT FROM AUTHOR]

Considering the characteristics of the servo system, such as disturbance, nonlinearity and high inertia, variable structure controller(VSC) based on extended state observers(ESO) are designed for the aim of quick, stable and high-accuracy controlling processes. The disturbances and high-order factors are estimated and compensated using ESO. Dynamic compensation reduces the motion system to approximately a triple integrator which can be easily controlled using VSC. Because ESO provides a high-frequency path for the dynamic state not modelled, the chatter of VSC is reduced. Through tests in the gun turret system, it was shown that this controller is superior to the engineering PID and general VSC. [ABSTRACT FROM AUTHOR]

Autonomous control system is designed for use on rocket launched unmanned aerial vehicles (RLUAV), Hierarchical architecture, planning and intelligent controller are first studied. Flow charts of modular programming for the autonomous flight tracking system and its specific implementation algorithm are then presented. Simulation results under Matlab/Simulink are finally given, from which the feasibility of autonomous flight control under hierarchical architecture were verified. [ABSTRACT FROM AUTHOR]