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Feedback linearization of the nonlinear model of a small-scale helicopter

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控制理论与应用（英文版） 2010年第3期8卷 301-308页

作者： Baoquan SONG Yunhui LIU Caizhi FAN College of Electronic Science and Engineering National University of Defense Technology Changsha Hunan 410073 China Department of Mechanical and Automation Engineering The Chinese University of Hong Kong Hong Kong China

In order to design a nonlinear controller for small-scale autonomous helicopters, the dynamic characteristics of a model helicopter are investigated, and an integrated nonlinear model of a small-scale helicopter for hovering control is presented. It is proved that the nonlinear system of the small-scale helicopter can be transformed to a linear system using the dynamic feedback linearization technique. Finally, simulations are carried out to validate the nonlinear controller.

关键词： Feedback linearization nonlinear model model helicopter

nonlinear model of the Carried-based UCAV in Final-Approach

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Nonlinear Model of the Carried-based UCAV in Final-Approach

A nonlinear Vortex Induced Vibration model of Marine Risers

第37届中国控制会议

作者： Qidan Zhu Zhibo Yang Peng Lu Yu Ma Harbin Engineering University

The model of the carrier-based UCAV is the basis for the design of the flight control system,which requires that its accuracy must conform to the design *** nonlinear model of the carrier-based UCAV is difficult to get *** aerodynamic layout of the carrier-based UCAV in this paper is used normal pneumatic layout design,with V wing and low-wing used small angle of sweepback and high aspect ratio.A complete nonlinear model is built through aerodynamic data fitting in this *** is necessary to model and simulate the control system of the aero-surfaces,on account of the V wing is controlled by the elevator and the *** control system of the aero-surfaces is distinguished from the previous control system of the carrier aircraft,it is difficult to use the traditional trim method.A new trim method is established on the balance of aerodynamic force and *** the simulated of the carrier-based UCAV model,it’s verified the accuracy by the responses to elevator and throttle step *** model of the carrier-based UCAV provides an accurate model for the future simulation research which is established in this paper.

关键词： Carrier-based UCAV nonlinear model Trim method Control system of the aero-surfaces Elevator and throttle

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Journal of Ocean University of China 2013年第1期12卷 32-36页

作者： LIU Juan HUANG Weiping Shandong Key Laboratory of Ocean Engineering Ocean University of China Construction Engineering Institute Agricultural University of Qingdao

With the exploitation of oil and gas in deep water, the traditional vortex induced vibration (VIV) theory is challenged by the unprecedented flexibility of risers. A nonlinear time-dependent VIV model is developed in this paper based on a VIV lift force model and the Morison equation. Both the inline vibration induced by the flow due to vortex shedding and the fluid-structure interaction in the transverse direction are included in the model. One of the characteristics of the model is the response-dependent lift force with nonlinear damping, which is different from other VIV models. The calculations show that the model can well describe the VIV of deepwater risers with the results agreeing with those calculated by other models.

关键词： vortex-induced vibration fluid-structure interaction lift force nonlinear model

nonlinear modeling and Identification of vessel based on constrained quadratic programming method

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Nonlinear Modeling and Identification of vessel based on con...

nonlinear Control of Magnetically Coupled Rodless Cylinder Position Servo System

第三十九届中国控制会议

作者： Xudong Wang Jin Zhao Tao Geng School of Artifical Intelligence and Automation Huazhong University of Science and Technology Guangdong Intelligent Roboticis Institute

In this research work, a vessel is used as a case study to investigate modeling and system identification. The discrete nonlinear 3-DOF state-space model with surge speed, lateral speed and yaw angle as state variables is established. A constrained quadratic programming method is proposed in this paper to identify parameters of nonlinear model, the steady-state data of vessel motions are the constraints and the transient-state data of vessel motions are used as training data to solve quadratic programming *** simulation results demonstrate the effectiveness of the method presented in this paper.

关键词： System Identification nonlinear model Constrained quadratic programming

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Chinese Journal of Mechanical Engineering 2023年第6期36卷 212-229页

作者： Yeming Zhang Demin Kong Gonghua Jin Yan Shi Maolin Cai Shuping Li Baozhan Lv School of Mechanical and Power Engineering Henan Polytechnic UniversityJiaozuo 454000China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027China School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China

Magnetically coupled rodless cylinders are widely used in the coordinate positioning of mechanical arms,electro-static paintings,and other industrial ***,they exhibit strong nonlinear characteristics,which lead to low servo control *** this study,a mass-flow equation through the valve port was derived to improve the control performance,considering the characteristics of the dynamics and throttle-hole ***,a fric-tion model combining static,viscous,and Coulomb friction with a zero-velocity interval was *** addition,energy and dynamic models were set for the experimental investigation of the magnetically coupled rodless cylin-der.A nonlinear mathematical model for the position of the magnetically coupled rodless cylinder was *** incremental PID controller was designed for the magnetically coupled rodless cylinder to control this system,and the PID parameters were adjusted online using RBF neural *** response results of the PID parameters based on the RBF neural network were compared with those of the traditional incremental PID control,which proved the superiority of the optimization control algorithm of the incremental PID parameters based on the RBF neural network servo control *** experimental results of this model were compared with the simulation *** average error between the established model and the actual system was 0.005175054(m),which was approximately 2.588%of the total travel length,demonstrating the accuracy of the theoretical model.

关键词： Magnetically coupled rodless cylinder nonlinear model Position control Radial basis function neural network(RBF-NN) Neural network(NN)

Optimal Preview Control for Automatic Carrier Landing System of Carrier-Based Aircraft with Air Wake

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Transactions of Nanjing University of Aeronautics and Astronautics 2017年第6期34卷 659-668页

作者： Li Meng Zhen Ziyang Gong Huajun Hou Min Huang Shuhong College of Automation Engineering Naniing University of Aeronautics and AstronauticsNanjing 211106P.R.China

Carrier-based aircraft carrier landing is a special kind of tracking control problem and not suitable for classical control methods,which may miss the desired performance or result in ***,we present an optimal preview control for automatic carrier landing system(ACLS)by using state information of system,as well as future reference information,which can avoid the shortcomings of classical control *** the flight performance of carrier-based aircraft is disturbed by air wake when the aircraft flies near the area of carrier stern,we design a disturbance rejection strategy to ensure that aircraft track the glide path with high precision and ***,carrier-based aircraft is a complex nonlinear ***,the nonlinear model of carrier-based aircraft can be linearized at equilibrium landing state and decoupled into the longitudinal model and the lateral ***,an optimal preview control system is *** simulation results of a carrier-based aircraft show that the optimal preview control system can effectively suppress air *** accuracy of optimal preview controller is higher than that of the proportional integral differential(PID)control system.

关键词： carrier-based aircraft carrier landing optimal control preview control nonlinear model

Memristance controlling approach based on modification of linear M–q curve

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Chinese Physics B 2014年第11期23卷 595-601页

作者：刘海军李智炜于红旗孙兆林聂洪山 College of Electronic Science and Engineering National University of Defense Technology

The memristor has broad application prospects in many fields, while in many cases, those fields require accurate impedance control. The nonlinear model is of great importance for realizing memristance control accurately, but the im- plementing complexity caused by iteration has limited the actual application of this model. Considering the approximate linear characteristics at the middle region of the memristance-charge （M-q） curve of the nonlinear model, this paper pro- poses a memristance controlling approach, which is achieved by linearizing the middle region of the M-q curve of the nonlinear memristor, and establishes the linear relationship between memristances M and input excitations so that it can realize impedance control precisely by only adjusting input signals briefly. First, it analyzes the feasibility for linearizing the middle part of the M-q curve of the memristor with a nonlinear model from the qualitative perspective. Then, the lin- earization equations of the middle region of the M-q curve is constructed by using the shift method, and under a sinusoidal excitation case, the analytical relation between the memristance M and the charge time t is derived through the Taylor series expansions. At last, the performance of the proposed approach is demonstrated, including the linearizing capability for the middle part of the M-q curve of the nonlinear model memristor, the controlling ability for memristance M, and the influence of input excitation on linearization errors.

关键词： memristor memristive system linear model nonlinear model

Magneto-thermo-mechanical characterization of giant magnetostrictive materials

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Rare Metals 2013年第5期32卷 486-489页

作者： Li Wang Bo-Wen Wang Zhi-Hua Wang Ling Weng Wen-Mei Huang Yan Zhou Province-Ministry Joint Key Laboratory of Electromagnetic Field and Electrical Apparatus Reliability Hebei University of Technology International Center for Materials Physics The Chinese Academy of Sciences School of Science Tianjin University of Commerce

The variations of magnetization and magneto- striction with temperature and stress were investigated through the analysis of the effective field, induced by temperature and stress. A nonlinear magnetostrictive model of giant magnetostrictive materials was proposed. The proposed model can be used to calculate the magnetostrictive characterization of giant magnetostrictive materi- als in different temperatures and under different stresses. The coupling effects of axial stress, magnetic field, and temperature on the magnetostriction of a Terfenol-D rod were numerically simulated as well as experimentally tested. Comparison between the calculating and experimental results shows that the proposed model can better describe the magneto-thermo-mechanical characteristics of Terfenol-D rod under different temperatures and compressive stress. Therefore, the proposed model possesses an important significance for the design of magnetostrictive devices.

关键词： nonlinear model Giant magnetostrictivematerials Temperature Stress

nonlinear Static and Dynamic Stiffness Characteristics of Support Hydraulic System of TBM

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Chinese Journal of Mechanical Engineering 2019年第6期32卷 26-34页

作者： Jianfeng Tao Junbo Lei Chengliang Liu Wei Yuan School of mechanical engineering Shanghai Jiaotong UniversityShanghai 200240China School of Electronic Information Jiangsu University of Science and TechnologyZhenjiang 212003China

Full-face hard rock tunnel boring machines(TBM)are essential equipment in highway and railway tunnel engineering *** the tunneling process,TBM have serious vibrations,which can damage some of its key *** support system,an important part of TBM,is one path through which vibrational energy from the cutter head is *** reduce the vibration of support systems of TBM during the excavation process,based on the structural features of the support hydraulic system,a nonlinear dynamical model of support hydraulic systems of TBM is *** influences of the component structure parameters and operating conditions parameters on the stiffness characteristics of the support hydraulic system are *** analysis results indicate that the static stiffness of the support hydraulic system consists of an increase stage,stable stage and decrease *** static stiffness value increases with an increase in the *** pre-compression length of the spring in the relief valve a ects the range of the stable stage of the static stiffness,and it does not a ect the static stiffness *** dynamic stiffness of the support hydraulic system consists of a U-shape and reverse *** bottom value of the U-shape increases with the amplitude and frequency of the external force acting on the cylinder body,however,the top value of the reverse U-shape remains *** study instructs how to design the support hydraulic system of TBM.

关键词： Tunnel boring machine Support hydraulic system nonlinear model Static stiffness characteristics Dynamic stiffness characteristics