共查询到20条相似文献,搜索用时 15 毫秒
1.
Z.-M. GET.-N. LIN 《Journal of sound and vibration》2002,251(3):519-542
The dynamic behavior of a gyrostat system subjected to external disturbance is studied in this paper. By applying numerical results, phase diagrams, power spectrum, period-T maps, and Lyapunov exponents are presented to observe periodic and choatic motions. The effect of the parameters changed in the system can be found in the bifurcation and parametric diagrams. For global analysis, the basins of attraction of each attractor of the system are located by employing the modified interpolated cell mapping (MICM) method. Several methods, the delayed feedback control, the addition of constant torque, the addition of periodic force, the addition of periodic impulse torque, injection of dither signal control, adaptive control algorithm (ACA) control and bang-bang control are used to control chaos effectively. Finally, synchronization of chaos in the gyrostat system is studied. 相似文献
2.
H.-K. CHEN 《Journal of sound and vibration》2002,255(4):719-740
The dynamic behavior of a symmetric gyro with linear-plus-cubic damping, which is subjected to a harmonic excitation, is studied in this paper. The Liapunov direct method has been used to obtain the sufficient conditions of the stability of the equilibrium points of the system. By applying numerical results, time history, phase diagrams, Poincaré maps, Liapunov exponents and Liapunov dimensions are presented to observe periodic and chaotic motions. Besides, several control methods, the delayed feedback control, the addition of constant motor torque, the addition of period force, and adaptive control algorithm (ACA), have been used to control chaos effectively. Finally, attention is shifted to the synchronization of chaos in the two identical chaotic motions of symmetric gyros. The results show that one can make two identical chaotic systems to synchronize through applying four different kinds of one-way coupling. Furthermore, the synchronization time is also examined. 相似文献
3.
Z.-M. GEJ.-S. SHIUE 《Journal of sound and vibration》2002,253(4):773-793
The dynamic behaviors of a rotational tachometer with vibrating support are studied in the paper. Both analytical and computational results are used to obtain the characteristics of the system. The Lyapunov direct method is applied to obtain the conditions of stability of the equilibrium position of the system. The center manifold theorem determines the conditions of stability for the system in a critical case. By applying various numerical analyses such as phase plane, Poincaré map and power spectrum analysis, a variety of periodic solutions and phenomena of the chaotic motion are observed. The effects of the changes of parameters in the system can be found in the bifurcation diagrams and parametric diagrams. By using Lyapunov exponents and Lyapunov dimensions, the periodic and chaotic behaviors are verified. Finally, various methods, such as the addition of a constant torque, the addition of a periodic torque, delayed feedback control, adaptive control, Bang-Bang control, optimal control and the addition of a periodic impulse are used to control chaos effectively. 相似文献
4.
The dynamic behaviors of the rotational machine with a hexagonal centrifugal governor which is subjected to external disturbance are studied in the paper. The Lyapunov direct method is applied to obtain conditions of stability of the equilibrium points of system. By applying numerical results, phase diagrams, power spectrum, Poincaré maps, and Lyapunov exponents are presented to observe periodic and chaotic motions. The effect of the parameter changes in the system can be found in the bifurcation and parametric diagrams. Finally, eight methods are used to control chaos effectively. 相似文献
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Chaos and chaotic control in a relative rotation nonlinear dynamical system under parametric excitation 下载免费PDF全文
This paper studies the chaotic behaviours of a relative rotation nonlinear dynamical system under parametric excitation and its control. The dynamical equation of relative rotation nonlinear dynamical system under parametric excitation is deduced by using the dissipation Lagrange equation. The criterion of existence of chaos under parametric excitation is given by using the Melnikov theory. The chaotic behaviours are detected by numerical simulations including bifurcation diagrams, Poincar map and maximal Lyapunov exponent. Furthermore, it implements chaotic control using non-feedback method. It obtains the parameter condition of chaotic control by the Melnikov theory. Numerical simulation results show the consistence with the theoretical analysis. The chaotic motions can be controlled to period-motions by adding an excitation term. 相似文献
7.
光学二次谐波浑沌控制 总被引:1,自引:1,他引:0
用变量延时反馈控制法对光学二次谐波系统的浑沌进行了有效的控制.通过对系统的最大李雅普诺夫指数分析,给出了确定可控参数区的方法.证明适当的延时量和反馈强度可以使浑沌得到稳定的控制,被控制系统的轨道是初始系统浑沌吸引子中的不稳定周期轨道. 相似文献
8.
光学二次谐波混沌的控制 总被引:2,自引:0,他引:2
用方波控制法对光学二次谐波系统的混沌进行了有效的控制,通过对系统的最大李雅普诺夫指数(MLE)的分析,给出了确定可控参数区的方法,证明适当的方波冲激强度和持续时间以及间隔时间可以使混沌得到稳定的控制,被控制系统的轨道是初始系统混沌吸引子中的不稳定周期轨道。 相似文献
9.
Chaos and chaos synchronization of the horizontal platform system are studied in this paper. Because of the non-linear terms of the systems, the systems exhibit both regular and chaotic motions. By applying various numerical results, such as phase portraits, Poincaré maps, time history and power spectrum analysis, the behaviors of the periodic and chaos synchronization are presented. The effects of the change of parameters in the system can be found in the bifurcation diagrams. Chaos synchronization of feedback methods in two coupled systems has been studied by Lyapunov exponent and coupling strength. Besides, phase effect of external excitations and the transient time in unidirectional synchronization also have been researched. 相似文献
10.
A NEW STRATEGY OF CHAOS CONTROL AND A UNIFIED MECHANISM FOR SEVERAL KINDS OF CHAOS CONTROL METHODS 下载免费PDF全文
Based on a general principle of physics that a physical system is in the most stable state if it is of the lowest energy stale, a new method for chaos control is proposed. A calculable generalized energy function in a nonlinear system is suggested for measuring control process, The Henon map and Lorenz system are taken as two typical examples to demonstrate the method. A series of stabilized periodic orbits as well aa inverse sequence of chaotic bands are obtained. At the same time, a unified mechanism of physics for several kinds of current cbaos control methods is studied using the idea proposed in this paper. 相似文献
11.
Y.-C. HSIAOP.C. TUNG 《Journal of sound and vibration》2002,254(1):163-174
This study describes a global approach of controlling chaos to reduce tedious waiting time caused by using conventional local controllers. With Euler's method, a non-autonomous system is approximated by a non-linear difference system and then an approximate global Poincaré map function is derived from the difference system by iterating one or more periods of a periodic excitation. Based on the map function, unstable periodic orbits embedded in a chaotic motion can be detected and a global controller for a targeted unstable periodic orbit is designed. The global controller makes all the unstable periodic orbits vanish except a targeted periodic orbit. Furthermore, a Lyapunov's direct method is applied to confirm that the global controller can asymptotically stabilize the unique periodic orbit. For practical applications, system models are usually unknown. To obtain a mathematical model, non-linear system identification based on the harmonic balance principle is applied to an unknown chaotic system of a noisy environment. Simulation results demonstrate that the global controller successfully regularizes a chaotic motion even if the chaotic trajectory is far from the targeted periodic orbit. 相似文献
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Circuitry implementation of a novel four-dimensional nonautonomous hyperchaotic Liu system and its experimental studies on synchronization control 下载免费PDF全文
Based on the three-dimensional Liu chaotic system, this paper
appends a feedback variable to construct a novel hyperchaotic Liu
system. Then, a control signal is further added to construct a novel
nonautonomous hyperchaotic Liu system. Through adjusting the
frequency of the control signal, the chaotic property of the system
can be controlled to show some different dynamic behaviors such as
periodic, quasi-periodic, chaotic and hyperchaotic dynamic
behaviours. By numerical simulations, the Lyapunov exponent
spectrums, bifurcation diagrams and phase diagrams of the two new
systems are studied, respectively. Furthermore, the synchronizing
circuits of the nonautonomous hyperchaotic Liu system are designed
via the synchronization control method of single variable coupling
feedback. Finally, the hardware circuits are implemented, and the
corresponding waves of chaos are observed by an oscillograph. 相似文献
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An experimental study of periodic and chaotic type aperiodic motions of a parametrically harmonically excited pendulum is presented. It is shown that a characteristic route to chaos is the period-doubling cascade, which for the parametrically excited pendulum occurs with increasing driving amplitude and decreasing damping force, respectively. The coexistence of different periodic solutions as well as periodic and chaotic solutions is demonstrated and various transitions between them are studied. The pendulum is found to exhibit a transient chaotic behaviour in a wide range of driving force amplitudes. The transition from metastable chaos to sustained chaotic behaviour is investigated. 相似文献
16.
Chaos and multiple periods are presented for the harmonically excited unsymmetrical spring and damping system with clearance. This paper demonstrates the non-linear behaviour of the motion through simulation and experiment. Intensive care and caution are taken in the experiments to observe the chaos and the multiple periods properly. The focus in this paper is mainly on the change of the bilinear spring stiffness ratio as a prime factor by which chaotic motions occur from quasi-periodic motion. Other investigations and effects on motion are also discussed for the changing of the extent of clearance. The investigations are based on frequency response curves. To understand the dynamics of the non-linearity of this model, all possible data processing and displaying techniques are taken into account. To observe the overall phenomena of this bilinear system, the resonance curves and the bifurcation diagrams are taken thoroughly for a wide frequency region. 相似文献
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基于参数切换算法和离散混沌系统, 设计一种新的混沌系统参数切换算法, 给出了两算法的原理. 采用混沌吸引子相图观测法, 研究了不同算法下统一混沌系统和Rössler混沌系统参数切换结果, 最后引入方波发生器, 设计了Rössler混沌系统参数切换电路. 结果表明, 采用参数切换算法可以近似出指定参数下的系统, 其吸引子与该参数下吸引子一致; 基于离散系统的参数切换结果更为复杂, 当离散序列分布均匀时, 只可近似得到指定参数下的系统; 相比传统切换混沌电路, 参数切换电路不用修改原有系统电路结构, 设计更为简单, 输出结果受方波频率影响, 通过加入合适频率的方波发生器, 数值仿真与电路仿真结果一致. 相似文献
19.
The chaotic behaviours in the p--Ge photoconductor system
are studied by changing the photo-excitation coefficient and the
routes and parameter conditions are given for chaos generation in
this system. A scheme for controlling chaos in the p--Ge
photoconductor is presented by adding an ac bias current. Numerical
simulations show that this scheme can be effectively used to control
chaotic states into stable period states for this system. Moreover,
the different period states with different period numbers can be
obtained by appropriately adjusting the amplitude, frequency, and
initial phase of the additional ac current. 相似文献
20.
研究了带负载电容的DC-DC buck变换器的分岔行为及其混沌控制问题,提到了一些新的有意义的结果.随着负载电容的增加,这种电路系统出现周期叠加序列窗口,且系统混沌运动的参数空间的测度逐渐趋于零,而且系统处在周期运动区时其电压转换效率高于系统处在混沌运动区时的电压转换效率,这些结果对于实际电路的设计具有较好的参考价值.同时,采用外加周期脉冲控制方法,能有效地实现该电路系统中的混沌控制. 相似文献