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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 pole assignment method is commonly used in the design of three-loop autopilot, and the constraints for the key parameter that the open-loop crossover frequency was blurred. By concluding the analytical relationship between control gains, the close-loop poles and the open-loop crossover frequency, the control system design problem is transformed into a judicious choice of the open-loop crossover frequency. Combined with engineering experience of the Canard layout missile, the constraint criteria and modified methods for the selection of the open-loop crossover frequency of the rudder bandwidth, the fin rate, the close-loop zeros and the gain polarity are discussed. The applicability of the criteria is verified in typical conditions.

Copyright of Piezoelectrics & Acoustooptics is the property of Piezoelectric & Acoustooptic 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.)

As the most basic control problem of the time delay integral system, it is difficult to control servo and disturbance rejection. In this study, a differential forward PID tuning method based on direct synthesis method and multiple dominant pole-placement method is proposed. This method mainly compares the coefficients of the characteristic equation composed of series filter and the time-delay integral controlled process with the actual desired characteristic equation. The third-order dominant pole is placed at -1/λ, and the second-order non-dominant pole is placed at -5/λ (λ is the adjustment parameter), so as to obtain the desired characteristic equation. Parameters of the controller are tuned to achieve the desired robustness. The corresponding Ms values can be obtained by selecting different tuning parameters, and the relationship curves between Ms and the tuning parameters can be fitted under the limited condition that the parameters are nominal, and the analytical form of the tuning rules can be given. The simulations of PIPTD, DIPTD and FOPTDI systems show that the IAE index can be reduced by average 35.79% and the TV index can be reduced by average 18.97%. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Applied Mechanics is the property of Chinese Journal of Applied Mechanics 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 pole assignment method is commonly used in the design of three-loop autopilot, and the constraints for the key parameter that the open-loop crossover frequency was blurred. By concluding the analytical relationship between control gains, the close-loop poles and the open-loop crossover frequency, the control system design problem is transformed into a judicious choice of the open-loop crossover frequency. Combined with engineering experience of the Canard layout missile, the constraint criteria and modified methods for the selection of the open-loop crossover frequency of the rudder bandwidth, the fin rate, the close-loop zeros and the gain polarity are discussed. The applicability of the criteria is verified in typical conditions. [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.)

For the instability of the system caused by parameter changes, this study investigates the filtering problem of closed-loop pole placement under region constraints,and a filtering system design method based on output feedback is proposed. In the presence of uncertainties in both the controlled system and the feedback filtering system, the solvability condition of the output feedback filtering system is given in the form of linear matrix inequalities. This condition ensures asymptotic stability of the closed-loop system, suppression of filtering error output with respect to changes below a given upper bound, and the proper placement of closedloop system poles in a specified region on the complex plane. This method is used to simulate and verify the longitudinal motion of a certain type of police unmanned aircraft. The distribution of closed-loop system poles is within the expected limits, indicating that the system is asymptotically stable and achieves the design objective. This demonstrates the effectiveness of the proposed method. [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 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.)

[Objective] Clearance between motion pairs is commonly observed in mechanisms due to manufacturing errors in components, assembly requirements, and wear of the mechanisms. When the mechanism operates at high speeds with large loads and small cross-sectional areas, components are susceptible to elastic deformation. This elastic deformation, combined with the clearance in motion pairs, significantly restricts the motion accuracy of the entire mechanism, leading to chaotic behavior and ultimately reducing its stability and reliability. Therefore, it is essential to investigate the influence of the coupling effect between the clearance of the motion pair and the flexible component on the motion state of the mechanism. [Methods] This paper proposes a chaos identification method for a rigid-flexible coupling experimental teaching platform with revolute clearance joints. First, a revolute clearance joint model was established based on the three-state model of "contact-separation-collision." In addition, a flexible beam element model was created using the absolute node coordinate method. Following this, a dynamic model of the rigid-flexible coupling six-link experimental platform with revolute clearance joints was established using the Lagrange multiplier method. Finally, both qualitative and quantitative identifications of chaotic phenomena in the six-link experimental platform were conducted using phase diagrams, Poincaré maps, and maximum Lyapunov exponents. The nonlinear characteristics of the rigid experimental platform with clearance and the rigid-flexible coupling experimental platform with clearance were compared and analyzed. Additionally, the effects of different clearance values, driving speeds, and friction coefficients on the nonlinear characteristics of the experimental teaching platform were studied. [Results] The results obtained using methods such as phase diagrams, Poincaré maps, and maximum Lyapunov exponents indicate that compared with the rigid experimental teaching platform mechanism with revolute clearance, the vibration frequency of the rigid-flexible coupling experimental teaching platform mechanism with revolute clearance is higher, leading to reduced stability and more pronounced chaotic phenomena. The chaotic behavior at the clearance of the revolute pair intensifies with an increase in clearance size and driving speed, whereas it weakens as the friction coefficient increases. [Conclusions] The coupling effect between the clearance of the motion pair and the flexibility of the component reduces the stability of the mechanism, leading to the emergence of chaos. The chaos identification method based on the experimental teaching of rigid-flexible coupling with revolute clearance proposed in this article can effectively distinguish the motion states of the mechanism. This method provides a systematic and comprehensive theoretical foundation for the study of nonlinear dynamics in high-precision, high-performance multilink mechanisms. This not only enhances students' ability to analyze and practice the nonlinear characteristics of mechanisms but also increases the diversity, intuitiveness, and engagement of the teaching process, ultimately improving the quality of education. [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 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.)

Aiming at the problem of slow training speed and poor convergence of deep reinforcement learning method for the autopilot control parameters training, an intelligent training method that converts three-dimensional control parameters into one-dimensional design parameters is proposed with the three-loop autopilot pole placement method as the core. The intelligent control architecture of offline deep reinforcement learning training and online multi-layer perceptron neural network real-time calculation is constructed, which improves the efficiency and convergence of deep reinforcement learning algorithm and ensures the rapid online tuning of control parameters under the condition of large-scale flight state changes. Taking a typical reentry aircraft as an example, the deep reinforcement learning training and neural network deployment are accomplished. The simulation results show that the training efficiency of the simplified reinforcement learning action space is higher, and the tracking error of the controller to the control command is less than 1.2% by the proposed parameter rapid tuning method based on deep reinforcement learning. [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 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.)

A radome parasitic loop model is established for the design of guidance system in radar homing missiles. The effects of radome parasitic loop on thestability and guidance performance parameters of guidance system are analyzed by using thedimensionless method. A real-time compensation for radome parasitic loop is proposed based on the theory of pole placement self-tuning control, and a simulation is performed. The research results indicate that the radome error slope leads to parasitic loop, which weakens the stability of guidance system, and deteriorates the stability when the time-to-go decreases. The parasitic loop may change the effective guidance time constant and effective navigation ratio of guidance system, thus reducing the guidance accuracy. The compensation method can make the parasitic loop be compensated effectively with good adaptability and robustness so that the stability and performance of guidance system are improved. [ABSTRACT FROM AUTHOR]

The articulated frame steering vehicles (ASV) are widely implemented in agriculture, mining, construction and forestry sectors due to their high maneuverability. The ASVs, however, are known to possess lower dynamic stability and yield high magnitude of whole-body vibration, which are reported to be harmful to the operators. Automatic driving system is thus necessary for the ASVs to exclude the human driver from detrimental operations, especially for the agricultural ASV. In order to enable the automation of ASV, path tracking strategies are essential to maintain the normal work of the vehicles. As the ASV dynamics significantly are different from the conventional vehicles with front wheel steering, the path tracking controller derived for conventional vehicles is considered not to be applicable for the ASVs. Moreover, large variations of the vehicle load and the off-road excisions challenge the robustness of path tracking algorithms. In this paper, a path tracking strategy is proposed for the ASVs on the basis of sliding mode control (SMC). The kinematic model of the ASV is derived neglecting the vehicle dynamics. Three measurable errors are defined to indicate the deviation of real path from reference path, i.e. lateral displacement error, orientation error and curvature error. These errors serve as the inputs in order to synthesize the SMC. The exponential reaching law is selected in order to increase the reaching speed and reduce chattering. The sign function of exponential reaching law is replaced by a continuous function to further suppress the chattering. Lyapunov function is then utilized in order to assess the system stability. The system transition performances in terms of response time, setting time and overshooting are tuned via pole placement method. The differential transformation method is implemented to determine the poles, in order to obtain the transition performances while preserving the system stability. Ackermann's formula is used to improve traditional pole placement algorithm and further design the control law. The open loop eigen-polynomial of the system is thus not requisite. Furthermore, the hardware-in-the-loop (HIL) simulation is conducted to evaluate real-time performance of the proposed control law. The HIL platform is set up on the basis of national instruments PXI-8110 and CRIO-9024 as well as a host computer. The real-time ASV kinematic model established in the MapleSim platform is downloaded into the PXI-8110 as the simulation plant, and the SMC path tracking algorithm compiled by Simulink is embedded to the cRIO-9024 as the real electronic control unit. The host computer couples the real-time vehicle model and the path tracking algorithm via the LabVIEW platform and displays the simulation status as the upper monitor. The path tracking algorithm then controls the vehicle to follow a circle path in real time. The results suggest that the simulated vehicle path is smooth and almost identical to the reference path. The 3 kinds of errors achieve steady state in 10 s. The proposed SMC controller is then demonstrated to be robust even neglecting the vehicle dynamics. The results also suggest that the SMC with Ackermann's formula can fulfill the prescribed request of the dynamic and the steady performance. The real-time performance of the path-tracking is even better than the off-line simulation. The simulation duration 60 s is equal to the calculating duration in the HIL simulation that means the time is synchronous. Compared with the real vehicle test, the HIL simulation is economical and efficient. This research can provide a reference for the design of agricultural ASV automatic driving system. [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.)

To solve the autonomous driving problems of underground mining truck, especially the path tracking problem, predecessors have researched articulated vehicle kinematic and control through the analysis of the kinematics modeling. Although articulated vehicle dynamic was taken into consideration in path tracking control fields, there would be also lack of accurate system modeling. So considering this multi variable, strong coupling, highly complex nonlinear dynamic system of articulated vehicles, it's difficult not only for establishment of an accurate model, but also for design of a precise control algorithm. Fuzzy hyperbolic model and the method of pole placement controller design in this article could provide a better way to solve these problems above. In this method, information with driver driving the truck included the vehicle kinematics relations, and by repeat of the same process, the vehicle dynamics relationship would be clearer. This method reduced the complexity in process modeling. The fuzzy hyperbolic model could cleverly convert the coefficient matrix of the nonlinear system to a constant matrix, then neural networks as a supervised learning method could be used to identify the parameters, which made the model more closed to the true model and it would be convenient to design a control algorithm. Pole assignment as a classical control algorithm was simple and effective and it could be appropriately applied into this kind of model. Following steps were needed to establish the fuzzy tangent model and the pole assignment method. Initially, the sample data, including the lateral displacement error and orientation error, were collected through the driver controlling articulated vehicle at the speed of 3 m/s. During the multiple times of driving in the same roadway, little change could be achieved for the lateral displacement error and the orientation error. After that, by using the improved adaptive BP neural network model and the mediation rate of error estimator based on the method of Cauchy robust, the system error of neural network learning was effectively reduced, and the fitting error and relative error of data were decreased. So the system was better matched, and the weights were well identified. Finally, the pole assignment method with choosing the appropriate poles was designed to control articulate angle. The Hardware-In-the-Loop (HIL) simulation platform was set up on the basis of PXI and C-RIO as a host computer. The kinematic model established in the Adams platform was downloaded into the PXI as the simulation plant, and the path tracking algorithm compiled by Simulink was embedded to the C-RIO as the real electronic control unit. The host computer coupled the vehicle model and the path tracking algorithm via the Labview platform and displayed the simulation status in the upper monitor. The results suggested in the process of driving this method could describe both the quantitative relation of the horizontal position deviation and course angle deviation with their rates of change, and could provide an accurate control. HIL results showed that the lateral displacement error, orientation error and the articulate angle of the vehicle were respectively controlled at 0.008 m, 0.07 rad (0.5°), 0.21 rad (12°). All the deviations were asymptotically stable. Overshoot and the response time were less than expectations and eventually stabilize. Articulated vehicles were maintained to the low level deviation and reference trajectory coincides with the track and also the simulation time and calculating time were all 80 s in the hardware in the loop simulation process, so the controller met the requirement of the real-time control performance. The method is demonstrated to be effective and reliable in path-tracking for the underground vehicles. [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 Journal of Northeastern University (Natural Science) is the property of Dongbei Daxue Xuebao 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 China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering 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 Northeastern University (Natural Science) is the property of Dongbei Daxue Xuebao 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.)

Robust H∞ performance is studied for a class of second-order linear systems with complex eigenvalues， especially the impact of imaginary part of complex eigenvalues on the H∞ performance is studied. It is found that when the real part of the complex eigenvalues is fixed， the impact of the imaginary part of the complex eigenvalues on the H∞ performance becomes little when the value of the imaginary part exceeds a threshold. Based on this observation， a fixed proportional relation between the imaginary part and the real part of the complex eigenvalues is found for a given system matrix under the framework of H∞ performance. Referring to the classical control theory of second-order systems in frequency domain， the relationship between the selection ranges of damping ratio and the complex eigenvalue is further discussed in the framework of H∞ performance， in which a reasonable explanation on the selection ranges of damping ratio is presented. This analysis procedure forms the time-frequency domain interaction synthesis method， which provides a theoretical guidance for the selection and determination of the desired closed-loop poles in the control theory based on the pole placement method. [ABSTRACT FROM AUTHOR]

Copyright of Coal Geology & Exploration is the property of Xian Research Institute of China Coal Research Institute 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 Electric Machines & Control / Dianji Yu Kongzhi Xuebao is the property of Electric Machines & 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.)

A linear parameter-varying (LPV) integrated control law is designed for a hypersonic vehicle to achieve trajectory control based on an altitude-horizontal trajectory control concept. The LPV output-feedback control theory and pole placement techniques are employed to design parameters of the control law within a Mach number envelope. Such a control law performs integrated control for longitudinal and lateral-directional dynamics of the vehicle, free from the scheme of inner and outer control loops of classical flight controls and ensuring robust and optimal control performance in the sense of L2-induced norm. A mathematical model of the hypersonic vehicle is developed in the Earth-centered-Earth-fixed reference frame. Earth rotation, Earth oblateness, and the second order harmonic perturbations of Earth are considered in the model. Numerical simulations are conducted to examine the performance of the LPV controller. The simulation results indicate that the closed-loop system of the hypersonic vehicle achieves D-stability. The LPV control law achieves a good performance in vehicle trajectory control and has sufficient robustness with respect to perturbations and sensor noise.

Copyright of Science Technology & Engineering is the property of Chinese Society of Technology Economics 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 Electric Drive is the property of Electric Drive 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 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 Electric Machines & Control / Dianji Yu Kongzhi Xuebao is the property of Electric Machines & 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.)

To solve the problem of coupling movements between degrees of freedom(DOF) of hyper-redundant shaking table while working with a load, a novel decoupling control strategy based on modal space is proposed. Linear model of hydraulic servo system is established and modal equation of hyper-redundant shaking table is given by considering hydraulic cylinder as a hydraulic spring. By standard modal matrix and its inverse matrix, the hyper-redundant shaking table is controlled in non-coupling modal space instead of DOF space. Three variables feedback control is employed in modal space to achieve decoupling control by pole placement. Simulation results show that the proposed decoupling control strategy can effectively improve tracking accuracy and reduce the dynamic coupling among DOF in both time and frequency domain. [ABSTRACT FROM AUTHOR]

This paper proposes two novel control methods for two-wheel self-balancing robot(TWSBR) ,which combines with traditional robot control theory. The first approach employs a classical modern control theory called pole-placement to design the state feedback controller, which is based on equilibrium point linearized model; the second one applies the method of LQR to study the linear system derived from the state-space equations of modern control theory. This paper also presents the simulation results of angle-control and displacement-control of TWSBR to show the effectiveness of the two design methods. [ABSTRACT FROM AUTHOR]

In order to explore dynamics modeling and control of supercavitating vehicles, memory effect of the cavity and its influence on the shape of cavity were researched based on the principle of cavity expansion independence. The cavitator orientation effect and cavity flotation were taken into account in computing the hydrodynamic forces of all parts of the supercavitating vehicle. Efficiency of the fin with the change of the fin immersion depth while the vehicle was traveling underwater was researched. A more precise nonlinear dynamics model of supercavitating vehicle was established. Robust pole placement controller was designed after exact input-output linearization. This controller has good control performance in depth tracking. Its shortcomings are input saturation and adverse effects of planing force. Model predictive control controller was designed to solve the problem of input saturation by restricting the distance between tail part of vehicle and the cavity wall, so that the planing force was avoided, the friction drag was reduced and the motion stability of the vehicle was improved. [ABSTRACT FROM AUTHOR]

To tolerate the limited faults such as thrust decline or actuator jamming of launch vehicles, an adaptive fault-tolerant control method based on radial basis function neural network (RBFNN) is proposed in this paper. The method is based on a limited faults dynamics model, and the baseline controller is designed based on the pole placement, using RBFNN to online identify and compensate the fault parameters and uncertain disturbances in the model. Then an adaptive fault-tolerant control law is designed based on Lyapunov theory. The simulation results show that the proposed adaptive control method can effectively ensure the attitude stability as well as control accuracy under the limited faults of launch vehicles, compared with the traditional PD control method.

The aerodynamic characteristics of aero-engine, which have a wide range of flight envelopes, vary drastically, so its controller is required to be able to adapt to a large range of parameter variations and have good robustness. To solve the above problem, based on the regional pole assignment, a new aero-engine multi-variable robust gain scheduled LPV control algorithm was proposed. Firstly, the Jacobian linearization method was used to obtain polynomial LPV model of aero-engine, which can describe its dynamic performance under certain conditions. Further, aiming at the polynomial LPV model, a LPV output feedback controller with the closed-loop system pole placement in a given region, which satisfied robust H∞ performance requirement, is designed using the LMI method. Then the grid method is used to transform the Lyapunov functional which depend on the scheduling parameters into a single Lyapunov function, which can guarantee the system has good steady performance. Finally, simulation studies have carried out based on a certain turbofan engine. The simulation results show that the designed controller can realize the accurate tracking of control commands with response time less than 1.6 s, over shoot less than 1% and steady-state tracking error less than 0.1%. The control system can guarantee the global stability and has good robustness in the design envelope.

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.)

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 Electric Machines & Control / Dianji Yu Kongzhi Xuebao is the property of Electric Machines & 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.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering 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.)