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    2024,22(1):1-21, DOI: 10.6052/1672-6553-2023-011
    Abstract:
    Magnetic attitude control systems have been widely used for low earth orbit satellites since the beginning of space era because of their reliability, lightweight, low cost and energy efficiency. Recently, small satellites are increasingly attractive. Magnetic controllers meet the limitations of small satellites and are considered as favorable candidates for small satellites. In this paper, the satellite magnetic attitude control algorithms, including algorithms for reaction wheel start up and unloading, passive and active magnetic attitude control algorithms, are covered. The algorithms herein are especially for small satellites. As for active magnetic attitude control algorithms, magnetic damping algorithms, the algorithms combining magnetic control with spin, constant speed flywheel and gravity gradient torque, and purely magnetic control algorithms are covered. Finally, the research is summarized.
    2024,22(1):22-26, DOI: 10.6052/1672-6553-2023-015
    Abstract:
    For the high-order Maggi equation of nonholonomic systems, when it meets certain conditions,the Maggi equation can be transformed into a Birkhoffian system.By constructing the generating function, the system is investigated numerically using the symplectic geometric algorithm of the Birkhoffian system.Compared with the above-mentioned algorithm with the classical Runge-Kutta method, Birkhoffian symplectic scheme is very accurate in a long-term tracing.
    2024,22(1):27-36, DOI: 10.6052/1672-6553-2023-007
    Abstract:
    For extensively existed high-aspect ratio structures in engineering, the bending-torsional-coupled vibration of the high-aspect ratio plate is studied for the first time. As the relative stiffness along the chordwise direction is far bigger than that of the spanwise, the chordwise section is simplified as a rigid body, while that in the spanwise direction is flexible. The Hamilton’s principle is applied to establish the governing equation of the bending-torsional-coupled vibration of the high-aspect ratio plate with simple supports at both ends. After projecting the governing equation into modal space via Galerkin method, the analytical results and numerical solutions of the bending-torsional-coupled vibration are obtained by the harmonic balance method and DQEM/DQM respectively. The convergence of the modal projection and the harmonic expansion are also verified. Finally, the influence of the external excitation on the forced vibration is studied. The results provide guidance for the design of high-aspect ratio structures in engineering.
    2024,22(1):37-42, DOI: 10.6052/1672-6553-2023-014
    Abstract:
    Acoustic diode can control the sound wave in only one direction and cannot propagate in the opposite direction, which has potential application in communication technology.However, most of the current acoustic diode designs are based on nonlinear effects that make the system only through new high frequencies and prevent the transmission of the original frequency.In this paper, we use a combination of asymmetric structures and weak nonlinear phononic crystals to propose a one dimensional acoustic diode model that enables asymmetric transmission of elastic waves and keeps the frequency constant.The model consists of a variable amplitude rod at the left end and a nonlinear spring mass chain at the right end.Theoretical analysis shows that the acoustic diode has forward, reverse and breakdown properties very similar to those of the electron diode. This paper has demonstrated the model by finite element simulation.
    2024,22(1):52-59, DOI: 10.6052/1672-6553-2023-003
    Abstract:
    Based on a single degree of freedom ship sailing in regular beam seas, the nonlinear rolling equation is established. The Runge Kutta methods is used to solve the differential equation of motion ,and the bifurcation diagram is plot by Poincaré surface of section. The process of different periodic attractors transforming into strange nonchaotic attractors under random wind excitation is studied by numerical simulation. It is found that a larger random excitation intensity is required to induce SNAs when the parameter is varied further from the chaotic range. The maximum Lyapunov exponent is used to verify the nonchaotic characteristics of the attractors, and singular continuous spectrum and the trajectories in the complex plane can demonstrate the strange property of the attractors.
    2024,22(1):60-68, DOI: 10.6052/1672-6553-2023-010
    Abstract:
    In order to simplify the dual parameter identification calculation of the dynamic system of the beam on Winkler Foundation, a new dimensionless method is proposed. The time and space coordinates of the system are linearly transformed to realize the complete normalization of the coefficients of the dynamic equation. The generalized frequency equation decoupled from the system parameters is obtained. It is found that the frequency and frequency ratio are only determined by the dimensionless span. Based on this discovery, a dual parameter identification algorithm based on the reciprocal relationship of frequency ratios is proposed. This algorithm can obtain the resolvent set of frequency and frequency ratio with respect to the dimensionless span under the corresponding boundary conditions by solving the generalized frequency equation once. After obtaining any two order measured frequencies of the system, the dual system parameters can be determined by relying on the linear transformation relationship established by the time and space reduction coefficients. Compared with the traditional two parameter identification algorithm, this algorithm has two characteristics:(1) The identification calculation only involves the solution and linear transformation of the univariate transcendental equation, which avoids the nonlinear iteration problem of the two parameter transcendental equation set in the traditional method, and can effectively simplify the identification calculation.(2) The change of any system parameter value only affects the size of the time and space reduction coefficients. Therefore, the resolvent set has generality applicable to any change of system parameter value, which can effectively avoid the repeated iterative solution caused by the change of system parameter value in traditional methods, and realize the generalization of the solution.
    2024,22(1):69-78, DOI: 10.6052/1672-6553-2022-064
    Abstract:
    This paper investigates the event-triggered output feedback adaptive fuzzy fault-tolerant control problem for switched nonlinear systems with actuator faults. Firstly, A mode-dependent state observer is established to estimate unmeasured states. Fuzzy logic systems are employed to approximate the unknown uncertainties. The constructed adaptive fuzzy fault-tolerant event-triggered controller can reduce the usage of the communication resources. Then, by multi-Lyapunov functions and average dwell time method, it is proved that all states of the closed-loop systems are SGGUB. In addition, zeno phenomenon can be excluded. Finally, the effectiveness of the method is verified by simulation result.
    2024,22(1):79-86, DOI: 10.6052/1672-6553-2023-027
    Abstract:
    The dynamical behaviors are studied for a sphere with a micro-void at the center under periodic perturbation loads, where the sphere is composed of a class of radially transversely isotropic incompressible neo-Hookean materials. A strongly nonlinear nonautonomous ordinary differential equation describing the radially symmetric motion of the micro-void is derived in terms of the equilibrium differential equation and initial-boundary conditions. Through qualitatively analyzing the solutions of the differential equation, some interesting qualitative behaviors of the micro-void are discussed. (1) For constant loads, the effects of material parameters and structural parameters on equilibrium points of the system are discussed, and the bifurcation behaviors, especially the secondary turning bifurcation of the micro-void are analyzed. By analyzing the well potentials, the phenomena of period and amplitude jump of the micro-void are discussed. (2) For periodic perturbation loads, the quasiperiodic and chaotic motions of the micro-void are discussed in terms of the secondary turning bifurcation by using the time response curves, Poincaré sections and the maximal Lyapunov characteristic exponents, the existence conditions of chaos are given, and the effects of periodic perturbation loads on the chaotic motions of the micro-void are further analyzed.
    2024,22(1):87-96, DOI: 10.6052/1672-6553-2023-026
    Abstract:
    In this paper, the negative stiffness element is integrated into the inertial nonlinear energy sink to form the negative stiffness inertial nonlinear energy sink (NS-INES), and this device is applied to suppress the vibration of the whole-spacecraft. Based on the reduction percentage of the maximum amplitude, the vibration suppression performance of the NS-INES is shown. Meanwhile, the influence of negative stiffness elements on the vibration suppression performance of inertial nonlinear energy sink is discussed by comparison. Finally, the influence and optimization of the parameters are discussed. The results show that the new NS-INES acting on the Whole-spacecraft has good vibration suppression performance.
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    2014,12(3):193-200, DOI: 10.6052/1672-6553-2014-046
    [Abstract] (2791) [HTML] (0) [PDF 748.46 K] (5775)
    Abstract:
    The spacecraft's ability to adapt to the harsh dynamics environment is critical for the whole space mission. Vibration test control technology is the key part of the dynamic environment test. The current progress, fundamental principles and key techniques development level of the spacecraft and vibration control algorithms overseas were analyzed. The basic ideas, effective ways and suggestions were given to domestic following research.
    2014,12(1):18-23, DOI: 10.6052/1672-6553-2013-068
    [Abstract] (2725) [HTML] (0) [PDF 1.13 M] (5499)
    Abstract:
    The electromechanical coupling model of cantilevered piezoelectric harvester was developed by considering the nonlinearities of piezoelectric material, based on Hamilton theory, Rayleigh-Ritz method, Euler-Bernoulli beam theory and constant electrical field across the piezoelectric element. The response characteristics of the system were investigated numerically, and the influences of piezoelectric material nonlinear coefficient on the system response were analyzed. By exploring the nonlinear characteristics of the piezoelectric vibrator near the resonant frequency, the nature of the multi-solutions and jump phenomena in the resonance region was revealed. The results were verified experimentally. which provides a theoretical basis for the study of nonlinear mechanism of piezoelectric power generation system.
    2017,15(5):385-405, DOI: 10.6052/1672-6553-2017-039
    [Abstract] (1710) [HTML] (0) [PDF 1.91 M] (5336)
    Abstract:
    In this review article, the growth and related academic communications in the dynamics of multibody systems are firstly surveyed. Then, the recent advances in the numerical algorithms for solving the dynamic equations of flexible multibody systems, the contact/impact dynamics of flexible multibody systems and the deployment of flexible space structures are systematically reviewed, together with several open problems of concern. Finally, some suggestions are made for the prospective researches on the dynamics of flexible multibody systems.
    2014,12(3):243-247, DOI: 10.6052/1672-6553-2014-054
    [Abstract] (2378) [HTML] (0) [PDF 1.07 M] (5148)
    Abstract:
    Random vibration test is very important to the aerospace equipment. The windage of ASD outside the frequency bandwidth was analyzed. The reason, premonition, affection and effective way were given. And the commonly used random vibration test and vibration test metrology standard for the ASD outside the frequency bandwidth were analyzed.
    2015,13(5):361-366, DOI: 10.6052/1672-6553-2014-064
    [Abstract] (1111) [HTML] (0) [PDF 826.19 K] (5103)
    Abstract:
    Dynamic and control systems often contain uncertain parameters that may result in uncertain predictions. In the interest of quantifying the effects of parameter uncertainties on response variability, this paper develops a stochastic response surface based method for the sensitivity analysis of uncertain parameters. Stochastic response surfaces were firstly constructed to describe the explicit relationships between uncertain parameters and responses. Then partial derivations were performed on the mathematical expressions of stochastic response surfaces in order to obtain sensitivity indices that simultaneously embody the effects of parameter means and standard deviations. Lastly, the developed method has been verified against a numerical cantilever beam containing uncertain geometric and material parameters. The sensitivity analysis results were compared with those given by the analysis of variance method.
    2016,14(2):97-108, DOI: 10.6052/1672-6553-2015-009
    [Abstract] (2179) [HTML] (0) [PDF 1.87 M] (4797)
    Abstract:
    Based on the current research status of multi agents system control theory and technology, the paper makes a detailed overview for unmanned ground systems. From two aspects of behaviour and task cooperative control for multi agents, the relevant theory and application problem is discussed. Moreover, some existed open problems are presented and a possible future development is proposed. For unmanned ground systems, cooperative control will be of great importance in promoting social and military benefits and maximizing the executive function of ground mission.
    2014,12(3):225-229, DOI: 10.6052/1672-6553-2014-051
    [Abstract] (2227) [HTML] (0) [PDF 1.38 M] (4765)
    Abstract:
    Based on the staggered solution procedure of ANSYS and CFX software, the fluid structure coupling response of projectile during tail slapping has been researched. Structural response was simulated by using FEM and flow field was simulated by using inhomogeneous model and SST turbulence model. Finally, the influences of fluid structure coupling effect have been analyzed and the change law of body stress has been given.
    2014,12(3):269-273, DOI: 10.6052/1672-6553-2014-043
    [Abstract] (3068) [HTML] (0) [PDF 336.30 K] (4723)
    Abstract:
    Aiming at the problem that the longitudinal modes of structural system of rocket need to be identified from its integral modes in engineering, a method that automatically identifies the longitudinal modes of structural system of rocket was proposed according to the theory of modal effective mass. Taking the vibration characteristics of system with lumped mass as a computing example, applying the finite element software, the beam model of system with lumped mass was established, and the longitudinal modes of the system were automatically identified based on the method. Compared with the system modal information calculated by the method of modal analysis, this automatic identification method not only can accurately identify the longitudinal modes of vibrating system, but also has automatic and high efficiency identification feature. It provides a theoretical basis for the dynamic model of POGO vibrating system in liquid rockets and other model of engineering systems to be accurately and promptly established.
    2012,10(1):21-26, DOI:
    Abstract:
    A discrete finite dimensional dynamical model was built to describe the space large overall motion of tethered satellite system with an infinite dimensional viscoelastic tether in a long time. The tethered satellite system is a complex nolinear dynamic system. Considering the tether’s viscoelasticity, distributed mass and space form, the established improved bead model can meticulously describe the tether’s vertical and horizontal vibration. According to tether’s characteristic of tensile and not compressive, the slack tether unit model was set up to accurately reflect real stress of tether. The determination of the number of degrees of freedom of the system was studied. Based on numerical integral calculation, the dynamic response was obtained via numerical simulation of the deployment, retrievement and retainment process of tethered satellite system in a long time. The result is convergent. The simulation proves the important role of the stable equilibrium position in the dynamics of tethered space system.
    2008,6(4):301-306, DOI:
    Abstract:
    The problem of P and PI feedback control to a time delay system was investigated,with the emphasis on the determination of the feedback gains that ensured the asymptotical stability of the delayed system. By means of Lambert W function,the feedback gain of P control can be expressed explicitly,so that the optimal feedback gain can be easily obtained. For the system under a PI control,the stable region of the feedback gains was determined on the basis of stability switches and D subdivision,and the optimal feedback gains that enabled the system to admit maximal stable margin were figured out numerically by using Lambert W function. From the viewpoint of computation,the present method is much simpler than the available methods.
    2014,12(2):183-187, DOI: 10.6052/1672-6553-2014-025
    [Abstract] (1174) [HTML] (0) [PDF 811.52 K] (4304)
    Abstract:
    PMSM due to little harmonic, high precision torque, commonly is used in the servo system and the high performance speed control system. In this paper,the physical model of PMSM is simplified and the mathematical model of the motor is established in order to facilitate research.Thispaper uses id=0 control manner which is the simplest manner is vector control methods,motor electromagnetic torque equation is established based on rotor field oriented vector control.The system model, speed and current control block are build and simulated with MATLAB/Simulink.Simulation results shows that the waveform is consistent with thoretical analysis,the model has fast response and small overshoot.The system runs stably with good dynamic and static characteristics. The simulation makes full use of modularization design. All the parameters and their influence on the system can be changed and observed.It also can easily validate the control strategies and select the most suitable one. So this kind of simulation is good for system design and adjusting and validating.
    2013,11(1):12-19, DOI: 10.6052/1672-6553-2013-003
    [Abstract] (2078) [HTML] (0) [PDF 530.95 K] (4294)
    Abstract:
    The dynamics of the whole aero-engine system has always been the important part that cannot be neglected in the research and design of the engine, as the framework of the engine, the vibration of the casing directly reflects the level of the whole aero engine vibration. In this paper, an analysis was made on the research of the problems and fault classification of aero-engine casing dynamics, and an overview was made on the research of present situation, development trend, problems and solutions of the domestic and foreign of casing dynamics, which expanded the present situation of the Inclusiveness problems of aero-engine casing dynamics. Finally, some proposals were put forward for the development of the casing dynamics suitable for our country aero-engine technology level.
    2013,11(4):357-362, DOI: 10.6052/1672-6553-2013-041
    [Abstract] (1231) [HTML] (0) [PDF 350.50 K] (4069)
    Abstract:
    At present, the main task of designing a mounting system of automotive engine powertrain is to select appropriate stiffness, position and angle of mounting components so that free-vibration modal frequency of the mounting system can avert from the exciting-force frequency at the idle speed of the engine and the natural frequency of vibration of the vehicle body and that the decoupling degree of each mode shape is increased as far as possible, so as to improve the vibration-isolation effect of the mounting system. The design of a mounting system based on strict decoupling at predetermined frequencies is to make the modal frequencies of the designed mounting system completely equal to the frequencies predetermined in accordance with the frequency planning of automotive design, and to enable strict decoupling of each mode shape of each mode, i.e., the decoupling degree of vibration energy in every direction equals to 1. Based on a free-vibration equation for a mounting system, this paper presents an equation system for designing a mounting system with strict decoupling at predetermined frequencies, provides a solving method for this equation system by using the theory of generalized inverse matrix or method of constructing function, so as to provide an optimal design method more efficient and simpler than the current modal optimization method of mounting system. Relevant example has validated the correctness of equations and solving method of the strict-decoupling design at predetermined frequencies.
    2014,12(3):205-209, DOI: 10.6052/1672-6553-2014-059
    [Abstract] (1983) [HTML] (0) [PDF 467.15 K] (4031)
    Abstract:
    This paper investigated the passive nonlinear vibration control method used for energy absorbing in structures of spacecrafts. The structure and the dynamic model of the nonlinear energy sink which could adapt to the space environment were proposed. As nonlinear spring could not be acquired easily in reality, we proposed a new design for the NES based on employing an asymmetric NES force which was generated by two pairs of aligned permanent magnets. Then, the dynamic model for a cantilever beam structure coupled with nonlinear energy sink had been built theoretically. In addition, the passive vibration suppression effect of the nonlinear energy sink on the cantilever beam structure under transient excitation had been analyzed through Galerkin method and numerical analysis method. The results showed that the NES acquired up to 92% dissipation of the system energy imposed by shock excitation, hence the NES could adapt to the space environment and improve the reliability of space system.
    2014,12(3):283-288, DOI: 10.6052/1672-6553-2014-061
    [Abstract] (2778) [HTML] (0) [PDF 479.50 K] (3988)
    Abstract:
    A method was presented to analyze the nonlinear flutter. Based on this method, the flutter characteristics of the high aspect wing were illustrated. The numerical results show that the flutter speed is decreased when the first horizontal bending mode involved. Secondly, this study discussed how the main direction of the composite influenced the character of the nonlinear vibration and flutter, and established the method of the flutter clipping to the high aspect wing. And the result shows that the stiffness of structure can be changed by changing the main direction of the composite. It mainly changes the horizontal bending mode, makes the main direction tend to the trailing edge, and then makes the section line move to the leading edge. Further analyzing the nonlinear flutter reveals that it is the changing of the horizontal bending mode that causes the flutter speed change obviously. And by the section line of this mode moves ahead, the flutter speed will become larger. In the study, two examples were illustrated to validate its truthiness.
    2016,14(3):247-252, DOI: 10.6052/1672-6553-2015-052
    [Abstract] (1651) [HTML] (0) [PDF 2.18 M] (3945)
    Abstract:
    Tires are the only carrier of the contact between the vehicle and road surface. Their mechanical property is important for analysis and control on the vehicle dynamic response. At present, the tire simulation mostly focuses on the steady state model. But it can not describe the dynamic characteristic of the tire accurately. Therefore, it plays a significant role to add the dynamic tire model in the vehicle dynamics simulation. The tire friction model in the multi body dynamical software ADAMS is static, where the friction is regarded as a static value. However, in actual, the friction between the tire and road surface is dynamic, and it should be a dynamic function of the relative velocity and displacement. To this end, in this paper, the dynamic tire LuGre model using the Matlab/Simulink software is constructed. Through connecting the interface with Adams/Car, co simulation between the vehicle model and the simulink tire model is carried out in order to achieve the dynamic contact between tire and road and improve the accuracy of vehicle system analysis.
    2014,12(1):36-43, DOI: 10.6052/1672-6553-2013-110
    [Abstract] (1841) [HTML] (0) [PDF 2.22 M] (3798)
    Abstract:
    The coupling nonlinear dynamic model of dual rotor system was established by using finite element method, and then the critical speed of revolution and mode shape were calculated by using the software MATLAB. In addition, the unbalance responses of dual rotor system were studied, and the vibration performances in different speeds of dual rotor casing systems were obtained. The research provides a theoretical basis for the design of the dual rotors system in engineering.
    2014,12(3):253-258, DOI: 10.6052/1672-6553-2014-056
    [Abstract] (1808) [HTML] (0) [PDF 1.00 M] (3767)
    Abstract:
    Taking account of the structural stiffness and the low order vibration frequencies, two schemes of multi-objective topology optimization were proposed to obtain the best aircraft lifting-surface structural design. Based on penalized density theory, the scheme one (named as constrain method) is to convert the multi-objective optimization to single-objective optimization by considering the minimum structural mass as the objective with constraints of reference points displacements and the low order vibration frequencies. The scheme two (named as the combination of constrain method and criterion function method) settles the multi-objective optimization by defining combined compliance index (CCI) as the objective, with the constraints of volume fraction and the low order vibration frequencies. The CCI is the function of structural compliance and low order vibration frequencies. Numerical results demonstrate the proposed schemes not only realize reducing the structural mass but also raise the first and second order frequencies.
    2014,12(3):201-204, DOI: 10.6052/1672-6553-2014-048
    [Abstract] (2061) [HTML] (0) [PDF 296.79 K] (3628)
    Abstract:
    Non-linear factors cannot be avoided in the design of aircraft structures. In this paper, a two-degree-of-freedom airfoil and cubic stiffness nonlinearities in pitching degree-of-freedom operating in supersonic flight speed regimes has been analyzed. The averaging method and the theory of flutter were used to analyze the nonlinear dynamic system of the dualistic airfoil in the supersonic flow. Then the correctness of the theoretical calculation was verified by numerical calculation, and the analysis result was given.
    2014,12(1):62-66, DOI: 10.6052/1672-6553-2013-097
    [Abstract] (1369) [HTML] (0) [PDF 832.87 K] (3457)
    Abstract:
    A spline finite point method was presented to study the natural frequency of arch. The displacement mode shape function of the arch free vibration was simulated with a linear combination of cubic B spline. The free vibration frequency equation of arch structures was derived according to Hamilton principle, in which the effect of the dead load was considered. Meanwhile, the effect of the dead load on the natural frequency of arch structures was analyzed. The results show that the natural frequency of arch is reduced. The effect of influence depends on the stiffness of the arch itself. When the arch stiffness is certain, the bigger the rise span ration and the radius to thickness ration, the higher the effect of the dead load on the natural frequency of arch structures.

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