• Current Issue
  • Archive
  • Most Downloaded
    Select AllDeselectExport
    Display Method:
    2021,19(5):1-7, DOI: 10.6052/1672-6553-2020-089
    Abstract:
    Both symmetric and asymmetric systems of one-degree-of-freedom double-impact Duffing oscillators are considered. The symmetry of Poincaré mapping is analyzed. By means of discontinuous mapping and the shooting method, periodic solution and its stability of the system are analyzed. Numerical simulation indicates that for the symmetric system, firstly a symmetric periodic orbit bifurcates into two antisymmetric period orbits, being of same stability, and the two antisymmetric periodic orbits go through two synchronous period-doubling bifurcations to form two antisymmetric chaotic attractors subsequently. Finally, the two antisymmetric chaotic attractors are fused into one symmetric chaotic attractor. For the asymmetric system, an asymmetric periodic motion can be characterized by a two-parameter unfolding of cusp bifurcation, and a typical symmetric breaking phenomenon takes place during pitchfork bifurcation.
    2021,19(5):8-12, DOI: 10.6052/1672-6553-2020-095
    Abstract:
    A new adaptive predictive control method is proposed to realize synchronization of fractional chaotic systems by combining adaptive control and predictive feedback control. Based on theory of fractional order Lyapunov stability, some new sufficient conditions for synchronization of fractional order chaotic systems are derived. Compared with the existing results, this method requires no prior knowledge of feedback gain, and has a fast convergence speed , which is also is easy to implement in experiments. Finally, numerical experiments further demonstrate the effectiveness of the proposed synchronization method.
    2021,19(5):13-22, DOI: 10.6052/1672-6553-2020-102
    Abstract:
    In this paper, projective synchronization between spatiotemporal networks with community structure and nonidentical nodes is investigated. Nodes in the same community are governed by the same dynamical function,while the functions for different communities are different. Based on topological characteristics of discrete spatiotemporal networks,an adaptive synchronous control method is designed. Several sufficient conditions for achieving projective synchronization are obtained by Lyapunov stability theory, which are further verified numerically by three different spatiotemporal chaotic networks.
    2021,19(5):23-32, DOI: 10.6052/1672-6553-2020-103
    Abstract:
    The paper investigates nonlinear dynamical characteristic of a macro fibre composite (MFC) plate subjected to transversal excitations. Nonlinear governing equations for the MFC plate are established based on Reddy''s first-order shear deformation theory, von Karman geometrical nonlinear kinematics and Hamilton’s principle. To analyze complex inner resonance phenomenon of the MFC plate, the first three order natural frequencies and the relationships of various internal resonances with different physical dimensions are discussed under different order excitations, and Galerkin’s approach is employed to discretize the partial differential governing equations into a three-degree-of-freedom nonlinear system. Then, stability analysis is conducted to investigate influences of related parameters on nonlinear behaviors of the composite plate. The results of numerical simulation show that increase of plate size will lead to decrease of both the natural frequencies and dynamic stability of the plate. Moreover, the different order transversal excitation has great effects on the nonlinear dynamics of the structure. The results will provide theoretical supports for practical engineering applications.
    2021,19(5):33-38, DOI: 10.6052/1672-6553-2020-088
    Abstract:
    A high-dimensional Melnikov method is developed to study bifurcations of multiple periodic solutions of nonlinear dynamical systems with parameters, and applied to study of complex nonlinear dynamical behaviors such as multiple periodic motions of honeycomb sandwich plates with negative Poisson''s ratio. By constructing the curvilinear coordinates and Poincaré map, the Melnikov function suitable for a four-dimensional nonlinear dynamical system with parameters is developed. The decision theorems on existence and number of multiple periodic solutions are obtained. Based on the theoretical results, the multiple periodic motions of honeycomb sandwich plate with negative Poisson''s ratio under in-plane and transverse excitations are investigated. The existence, number and parameter control conditions of periodic orbits are derived. The influence of transverse excitation on the system''s dynamical behaviors is discussed. Under certain parameter conditions, there exist at most four periodic orbits, and the phase portrait configurations are given by numerical simulations to verify the theoretical results.
    2021,19(5):39-45, DOI: 10.6052/1672-6553-2020-096
    Abstract:
    Many results has been obtained regarding anti-penetration performance of ceramic/metal and ceramic/fiber composite structure influenced by circumferential restriction, but relevant research of ceramic composite structure containing aluminum foam is still absent. This paper studies effects of circumferential restriction for anti-penetration performance of ceramic composite structure containing aluminum foam, based on experiments and numerical simulations. The results show that circumferential restriction is the key mechanism of damage characteristics of ceramic composite structure containing aluminum foam, ascircumferential restriction of ceramic and aluminum foam plate could limit crack propagation of ceramic plate and aluminum foam plate and increase resistance, thus enhancing energy consumption of composite structure, and improving the anti-penetration performance.
    2021,19(5):46-51, DOI: 10.6052/1672-6553-2021-001
    Abstract:
    By combining the quasi-zero stiffness structure (QZS) with an X-shaped isolator, a new passive X-shaped quasi-zero stiffness isolator (X-QZS) is designed. By replacing the linear spring of the X-shaped isolator with the QZS, excellent performance in ultra-low frequency band is obtained. Harmonic balance method and arc length method are used to solve the motion equations established by the Lagrange equations in order to obtain approximate analytical solutions ,which are then verified by numerical method. Steady-state responses to harmonic displacement excitation with different structural parameters are compared. The vibration isolation performance are analyzed. The results demonstrate that X-QZS can achieve better isolation than QZS in the ultra-low frequency range, with lower resonance frequency and wider vibration isolation band.
    2021,19(5):52-57, DOI: 10.6052/1672-6553-2020-104
    Abstract:
    A self-powered shock absorber combining vibration energy recovery and vibration control can achieve better vibration suppression without relying on external energy, which can effectively improve drive comfort and fuel economy of vehicle. In this paper, we analyze nonlinear characteristics of self-powered intelligent shock absorber. Furthermore, we systematically investigate the self-coupling control strategy of vibration energy recovery and vibration control. The self-feedback with Karnopp control rules suspension is modeled, and the active control strategy is applied to self-powered intelligent shock absorber. The control strategy was simulated using MATLAB/Simulink, which was compared with the self-feedback control and the passive suspension control. The results demonstrate that the dynamic displacement of tire and suspension are further reduced, and the peak acceleration of the body is reduced by almost half, meaning that the performance of vehicle suspension is improved effectively.
    2021,19(5):58-63, DOI: 10.6052/1672-6553-2020-101
    Abstract:
    Aiming at characteristics of the lower limb assisted exoskeleton knee joint position servo systems, such as high servo accuracy, large impact torque and wide load range, a sliding mode control strategy of position servo system based on fuzzy rules is proposed. This strategy designs a new type of sliding mode surface with integral terms. The structure of the fuzzy adjustment part is of single input and double output. Fuzzy rules are used to adjust the new terminal sliding mode approach rate to suppress sliding mode chattering. Both experiments and simulations demonstrate that the control strategy has good stability and servo tracking performances, and strong robustness with respect to load disturbances.
    2021,19(5):64-68, DOI: 10.6052/1672-6553-2020-097
    Abstract:
    Aiming at actual control of undirected networks,an effective method of setting the input matrix is proposed to completely control the network. This method shows that under certain conditions,the entire network can be controlled through controlling the network core only. The theoretical results are further verified by an illustrative example,which demonstrates the correctness and feasibility of theoretical conclusions. This study reveals the dominated role played by important structures in undirected networks and provides an effective method for controlling complex networks.
    2021,19(5):69-79, DOI: 10.6052/1672-6553-2021-017
    Abstract:
    Equivalent mechanical model can be used to describe liquid sloshing of a liquid-filled vehicle with small amplitude sloshing. However, in the study of effect of liquids on rigid body, modeling from the perspective of frequency domain is still absent. In this paper, based on the known equivalent mechanical models associated with various modes of liquid, the transfer function of longitudinal mode rudder deflection angle to attitude is given by the principle of virtual power and the principle of linear small disturbance. According to the concept of dominant pole, the high-order system of liquid-filled vehicle is approximated by typical transfer functions of second-order systems. The results show that the liquid mass and moment of inertia mainly affect the transfer coefficient and time constant of the vehicle, which reduce the maneuverability and the natural frequency of longitudinal mode of the vehicle, while the liquid sloshing mainly affects the relative damping coefficient in the typical transfer function, which reduces the longitudinal relative stability of the vehicle.
    2021,19(5):80-87, DOI: 10.6052/1672-6553-2020-109
    Abstract:
    In this paper, global bifurcation behavior of five-dimensional Hindmarsh-Rose(HR) neuron model is analyzed in detail under the interaction of magnetic flux and electric field variables. By means of numerical simulation, biparametric bifurcation diagram, ISI bifurcation diagram and maximum Lyapunov exponent diagram of the neuron system are constructed, and it is found that the system has period-doubling bifurcation, inverse period-doubling bifurcation, period-adding bifurcation and chaotic structure with "jaggedness" on the biparametric plane. In addition, based on the stability theory of Lyapunov and the idea of adaptive synchronization, the corresponding response system is constructed by taking the chaotic system as a driving system, and an appropriate controller is selected to realize synchronization between the driving system and the response system, with unknown parameters were identified. Numerical simulation shows effectiveness and feasibility of this method.
    2021,19(5):88-96, DOI: 10.6052/1672-6553-2021-002
    Abstract:
    According to actual contact relationships between the traction plate and stringing pulley in tension stringing construction of transmission lines, a multi-body motion system is constructed including traction rope, traction plate, conductor and double-pulley structure. A contact judgment method between wire rope, conductor, traction plate and double-pulley is then proposed in accordance with the actual situation. Combined with the spatial position relationship between the components, the force expressions of the element node are proposed based on the finite particle method, and the contact forces of the traction plate to the pulley under different contact conditions are obtained by penalty function method, leading to the dynamic calculation method for the contact collision between the traction plate and the double-pulley structure. According to the actual tension stringing construction, variations of pulley loads and swing angles during the contact process are calculated and analyzed. The rules of traction force, maximum contact force, pulley load and swing amplitude are summarized under the influence factors such as suspension length and traction plate thickness. The proposed calculation method can guide the structural design, construction and installation of traction plate and pulley in engineering, and provide technical reference for the construction of transmission lines.
    Select AllDeselectExport
    Display Method:
    2014,12(3):193-200, DOI: 10.6052/1672-6553-2014-046
    [Abstract] (1996) [HTML] (0) [PDF 748.46 K] (3968)
    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] (2043) [HTML] (0) [PDF 1.13 M] (3856)
    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.
    2015,13(5):361-366, DOI: 10.6052/1672-6553-2014-064
    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.
    2014,12(3):243-247, DOI: 10.6052/1672-6553-2014-054
    [Abstract] (1797) [HTML] (0) [PDF 1.07 M] (3658)
    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.
    2017,15(5):385-405, DOI: 10.6052/1672-6553-2017-039
    [Abstract] (1138) [HTML] (0) [PDF 1.91 M] (3602)
    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):269-273, DOI: 10.6052/1672-6553-2014-043
    [Abstract] (2378) [HTML] (0) [PDF 336.30 K] (3370)
    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.
    2014,12(3):225-229, DOI: 10.6052/1672-6553-2014-051
    [Abstract] (1519) [HTML] (0) [PDF 1.38 M] (3342)
    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.
    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.
    2016,14(2):97-108, DOI: 10.6052/1672-6553-2015-009
    [Abstract] (1320) [HTML] (0) [PDF 1.87 M] (2985)
    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.
    2013,11(1):12-19, DOI: 10.6052/1672-6553-2013-003
    [Abstract] (1408) [HTML] (0) [PDF 530.95 K] (2881)
    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:
    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):253-258, DOI: 10.6052/1672-6553-2014-056
    [Abstract] (1432) [HTML] (0) [PDF 1.00 M] (2673)
    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(2):183-187, DOI: 10.6052/1672-6553-2014-025
    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.
    2014,12(3):283-288, DOI: 10.6052/1672-6553-2014-061
    [Abstract] (1941) [HTML] (0) [PDF 479.50 K] (2653)
    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] (1197) [HTML] (0) [PDF 2.18 M] (2593)
    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] (1198) [HTML] (0) [PDF 2.22 M] (2570)
    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):205-209, DOI: 10.6052/1672-6553-2014-059
    [Abstract] (1581) [HTML] (0) [PDF 467.15 K] (2564)
    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):201-204, DOI: 10.6052/1672-6553-2014-048
    [Abstract] (1671) [HTML] (0) [PDF 296.79 K] (2524)
    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:
    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.

External Links Links

WeChat

Mobile website