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Earthquake Science 2019年第5期32卷 187-196页

作者： Feng Qian Haiming Zhang Department of Geophysics School of Earth and Space SciencesPeking UniversityBeijing 100871China

In this study,we attempted to perform an earthquake source dynamic inversion to obtain dynamic parameters on fault system with complex geometry.The forward modeling of the spontaneous rupture process is carried out using a boundary integral equation method(BIEM)based on unstructured meshing,and the inversion method is implemented by a genetic algorithm based on a parallel acceleration of the GPU.The source model in this study is a branched fault,which is described by two physical parameters,the initial stress T0 and the critical slip-weakening distance Dc.We investigated the effect of the inherited parameters on the accuracy and convergence of the inversion simulation.Numerical results showed that if a set of parameters are assigned properly,the inversion of rupture parameters is accurate and converges fast.It is easy to converge to a local optimal solution during the inversion process if inappropriate inherited parameters are selected.Compared with T0,D。has better convergence and accuracy in.the inversion process.

关键词： dynamic inversion genetic algorithm initial stress critical slip-weakening distance

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Guidance and Control for UAV Aerial Refueling Docking Based on dynamic inversion with L_1 Adaptive Augmentation

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Transactions of Nanjing University of Aeronautics and Astronautics 2015年第1期32卷 35-41页

作者：袁锁中甄子洋江驹 College of Automation Engineering Nanjing University of Aeronautics and Astronautics

The guidance and control for UAV aerial refueling docking based on dynamic inversion with L1 adaptive augmentation is studied.In order to improve the tracking performance of UAV aerial refueling docking,aguidance algorithm is developed to satisfy the tracking requirement of position and velocity,and it generates the UAV flight control loop commands.In flight control loop,based on the 6-DOF nonlinear model,the angular rate loop and the attitude loop are separated based on time-scale principle and the control law is designed using dynamic inversion.The throttle control is also derived from dynamic inversion method.Moreover,an L1 adaptive augmentation is developed to compensate for the undesirable effects of modeling uncertainty and disturbance.Nonlinear digital simulations are carried out.The results show that the guidance and control system has good tracking performance and robustness in achieving accurate aerial refueling docking.

关键词： aerial refueling dynamic inversion guidance algorithm L1adaptive augmentation

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Flight Control of Unpowered Flying Vehicle Based on Robust dynamic inversion

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Flight Control of Unpowered Flying Vehicle Based on Robust D...

第25届中国控制会议

作者： Liu Zhiping, Zhou Fengqi, Zhou Jun College of Astronautics, Northwestern Polytechnical University, Xi''an 710072

In this paper, a robust nonlinear dynamic inversion (NDI) control law is proposed for the attitude tracking of the unpowered flying vehicle, which is a highly nonlinear strong coupled and time-varying

关键词： dynamic inversion Unpowered flying vehicle Proportional navigation guidance Nonlinear system

Stable Discrete-time Adaptive Control for Robotic Manipulators via Neuro-fuzzy dynamic inversion

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Stable Discrete-time Adaptive Control for Robotic Manipulato...

2003年中国智能自动化会议

作者： Fu-Chun Sun Han-Xiong Li Zeng-Qi Sun Hua-Ping Liu Dept. of Computer Science and Technology, State Key Lab of Intelligent Technology & Systems, Tsinghua University, Beijing 100084 Dept. of Manufacturing Engineering and Engineering Management, City University of Hong Kong, Hong Kong, P.R.China

In this paper, we present a stable discrete-time adaptive tracking controller using a neuro-fuzzy (NF) dynamic inversion for a robotic manipulator with its dynamics approximated by a dynamic T-S fuzzy model. NF dynamic inversion is used to compensate for the robot inverse dynamics for a better tracking performance. By assigning the dynamics of the dynamic NF (DNF) system, the dynamic performance of the robot control system can be guaranteed for the initial control stage, which is very important for enhancing system stability and adaptive learning. The discrete-time adaptive control composed of NF dynamic inversion and NF variable structure control (NF-VSC) is developed to stabilize the closed-loop system and ensure the high-quality tracking. The NF-VSC helps the stability of the controlled systems, and improves the system dynamic performance during the NF learning. The system stability and the convergence of tracking errors are guaranteed by the Lyapunov stability theory, and the learning algorithm for the DNF system is obtained thereby. An example is given to show the viability and effectiveness of the proposed control approach.

关键词： Robotic manipulators neuro-fuzzy systems dynamic inversion neuro-fuzzy variable structure and adaptive control

Adaptive Nonlinear dynamic inversion Control for Airborne Dispenser Uncertain System

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Adaptive Nonlinear Dynamic Inversion Control for Airborne Di...

第二十九届中国控制会议

作者： SUN Xiaoxu 1,SHAN Jiayuan 2 1.School of Aerospace Engineering,Beijing Institute of Technology Beijing 100081,P.R.China2.Beijing Institute of Technology,Beijing 100081,P.R.China

This An approach to design dynamic inversion controller with adaptive compensator for airborne dispenser has been presented in this paper.The basic control law is designed using the dynamic inversion method,and the online learning neural networks are used to compensate the system errors and external disturbance.The online weights and thresholds tuning rules are deduced according to the tracking error performance functions by Lyapunov method.And it can guarantee the system to keep stable.With the changes of the flying states,the controller can adapt to the fast varying states of the system,and has preferable performance.Simulation results show that limitation of needing accurate mathematical model in dynamic inversion can be released.And the robustness of the whole system is greatly improved.

关键词： dynamic inversion Neural Network Adaptive Nonlinear Controller Inverse Error.

Transition Flight Control Using Adaptive Neutral Network dynamic inversion for Canard Rotor/Wing UAV

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Transition Flight Control Using Adaptive Neutral Network Dyn...

第26届中国控制与决策会议

作者： Wendong Gai Jing Zhang Liangsong Huang Yuxia Li College of Information and Electrical Engineering Shandong University of Science and Technology

The problem of designing transition flight controller via improved adaptive neural network dynamic inversion for Canard Rotor/Wing(CRW) UAV is studied. The transition control strategy from rotary-wing mode to fixed-wing mode is derived according to the flight characteristic analysis. The controller is composed of trajectory outer-loop and attitude inner-loop. The dynamic inversion method is used to design these loops. In addition, the angular rate error equations with proportional-integral desired dynamics are used to design the adaptive update law for compensating the system model error. The main advantage of this approach is its ability of the fast adaptation that leads to good steady and transient performance as well as simple design process. The longitudinal nonlinear dynamic simulations show that this approach improves the stability and transient response of attitude angle and achieves the transition flight control of the CRW UAV successfully.

关键词： Flight Control Adaptive Neural Network Canard Rotor/Wing UAV dynamic inversion

Analysis of Channeling-Path Phenomena in a Complex Fault-Block Reservoir with Low Recovery Factor and High Water-Cut Ratio

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Fluid dynamics & Materials Processing 2023年第2期19卷 361-377页

作者： Qunyi Wang Xiaoli Ma Yongbin Bi Haiyan He Xiao Gu Tongjing Liu Lekun Zhao Jidong Oilfield Company Ltd.Exploration and Development Research Institute Tangshan063000China Unconventional Oil and Gas Institute China University of Petroleum(Beijing)Beijing102249China College of Petroleum Engineering China University of Petroleum(Beijing)Beijing102249China

Current methods for the analysis of channeling-path phenomena in reservoirs cannot account for the influence of time and space on the actual seepage behavior.In the present study,this problem is addressed considering actual production data and dynamic characteristic parameters quantitatively determined in the near wellbore area by fitting the water-cut curve of the well.Starting from the dynamic relationship between injection and production data,the average permeability is determined and used to obtain a real-time quantitative characterization of the seepage behavior of the channeling-path in the far wellbore area.For the considered case study(Jidong oilfield),it is found that the seepage capacity of the channeling-path in the far wellbore area is far less(10 times smaller)than that of the channeling-path in the near wellbore area.The present study and the proposed model(combining near wellbore area and far wellbore area real-time data)have been implemented to support the definition of relevant adjustment measures to ultimately improve oil recovery.

关键词： Complex fault-block reservoirs channeling path quantitative identification characteristic parameters dynamic inversion

inversion Control of Aircraft Herbst Maneuver with Nonlinear dynamic Root-finding

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Inversion Control of Aircraft Herbst Maneuver with Nonlinear...

第30届中国控制与决策会议

作者： Sheng Zhang Fei Liao Weiqi Qian Kaifeng He Computational Aerodynamics Institute China Aerodynamics Research and Development Center China State Key Laboratory of Aerodynamics Facility Design and Instrumentation Institute China Aerodynamics Research and Development Center

Root-finding techniques may be utilized in designing the controller, and the heavy numerical iteration brought by the conventional methods is unappealing. A nonlinear dynamic Root-finding（DRF） technique is developed and embedded in the time-scale separation based dynamic inversion（DI） controller to realize the aircraft Herbst post-stall maneuver. Different from the conventional root-finding methods, the proposed method is derived from the dynamics stability theory. The employment of this method makes the control logic fairly simple and the resulting controller is of appealing integral form. Under reasonable assumptions, the stability of the further developed DI control system is guaranteed. Simulation results verify the DRF method’s efficiency, precision and reliability in solving the state-dependent nonlinear implicit algebraic equation. This technique may be applied to other control problems.

关键词： Aircraft flight control Post-stall maneuver Herbst maneuver dynamic inversion dynamic root-finding

Synthesis of Fractional-order PI Controllers and Fractional-order Filters for Industrial Electrical Drives

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IEEE/CAA Journal of Automatica Sinica 2017年第1期4卷 58-69页

作者： Paolo Lino Guido Maione Silvio Stasi Fabrizio Padula Antonio Visioli IEEE Dipartimento di Ingegneria Elettrica e dell’Informazione Politecnico di Bari Department of Mathematics and Statistics Curtin University Department of Mechanical and Industrial Engineering University of Brescia

This paper introduces an electrical drives control architecture combining a fractional-order controller and a setpoint pre-filter. The former is based on a fractional-order proportional-integral(PI) unit, with a non-integer order integral action, while the latter can be of integer or non-integer type. To satisfy robustness and dynamic performance specifications, the feedback controller is designed by a loop-shaping technique in the frequency domain. In particular, optimality of the feedback system is pursued to achieve input-output tracking. The setpoint pre-filter is designed by a dynamic inversion technique minimizing the difference between the ideal synthesized command signal(i.e., a smooth monotonic response) and the prefilter step response. Experimental tests validate the methodology and compare the performance of the proposed architecture with well-established control schemes that employ the classical PIbased symmetrical optimum method with a smoothing pre-filter.

关键词： dynamic inversion electrical drives fractionalorder PI controller loop-shaping set-point pre-filter

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Sliding mode decoupling control of a generic hypersonic vehicle based on parametric commands

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Science China(Information Sciences) 2015年第5期58卷 168-181页

作者： WANG Peng TANG GuoJian WU Jie College of Aerospace Science and Engineering National University of Defense Technology

A sliding mode decoupling attitude controller based on parametric commands is proposed for a generic hypersonic vehicle(GHV). This vehicle model has fast time variability and strong coupling, is highly nonlinear, and includes uncertain parameters. The design of the controller takes these features into account.First, for the purpose of decoupling, the inner loop of the controller is designed using the dynamic inversion(DI) method. Input/output linearization is achieved using full-state feedback to globally linearize the nonlinear dynamics of selected controlled outputs. Second, to improve the robustness of the attitude control system, the sliding mode control(SMC) method is used to design the outer loop of the controller. Although the DI and SMC methods result in decoupling and robustness, there exists serious inconsistency between the commands of the attitude angles and the commands of the first-order differential of the attitude angles. To solve this problem and achieve a trade-off between dynamic response speed and attitude-tracking precision, we propose a parametric method for calculating the commands of the first-order differential of the attitude angles. Finally,simulation studies are conducted for the trimmed cruise conditions of 33.5 km altitude and Mach 15, and the responses of the vehicle to the step commands of pitch angle, yaw angle, and rolling angle are examined. The simulation studies demonstrate that the proposed controller is robust with respect to the uncertain parameters and atmospheric disturbance and meets the performance requirements of the GHV with acceptable control inputs.

关键词： generic hypersonic vehicle sliding mode control dynamic inversion parametric commands de-coupling robustness