Abstract:Based on analytic structural mechanics, the interface of the two nearest substructures extends to a region with a certain width, named interbelt, where the interbelt theory and the corresponding algorithm under the framework of symplectic system can analyze the nonlocal characteristic of structures. The integral of time delay elasticity system in analytic dynamics still has many questions in theoretical aspects, which needs to be made clear. There are simulative relations between analytic dynamics and analytic structural mechanics, hence the interbelt theory can be applied in solving the integral problems of time delay elasticity system, and the corresponding arithmetic can be founded based on symplectic system. Numerical examples were carried out for the validity of the theory and algorithm developed. As a basic research work, the present study illustrates well the potential of the interbelt as well as the symplectic algorithm and is valuable for the further research.

Abstract:To perfect the axiom system of classical mechanics, a new fundamental principle,named Zero-principle, is established on the basis of three foundation-stones: 1) the concealing-displaying model, 2) the mode-assumption of displaying force,3）the μ-proof. The conclusion of the principle is summarized into three equivalent ‘zero-force systems’. The new principle makes a series of important contributions: 1）Raise Newton’s 2nd law into a theoretical principle, so that it is no longer fully experiment-based. 2) Make D’Alembert’s principle become a principle independent of Newton’s 2nd law.3）Establish a reformed principle,named principle of minimum freedom, including Gauss’ priniciple of least constraint as a particular case. As a consequence,the so-called Z-paradox in Gauss’ principle is solved. 4）Provide a brief natural proof of new Hamilton’s principle of ‘least action’. 5) After generalizing,, the Zero- principle is applied to the impulsive condition.

Abstract:Difference discrete variation principle and Noether theorem of discrete holonomic systems in event space were studied. By the difference discrete variation approach,the difference discrete variation principle of discrete holonomic systems in event space was derived. The discrete equations of motion of the system were established. The criterion of Noether symmetry of the system was given. The discrete Noether conserved quantity and the condition for its existence were obtained. Finally,an example was discussed to show the applications of the results.

Abstract:For static bending and free vibration problems of moderately thick plate, by introducing two auxiliary functions and using the differential equations and the boundary conditions based on Reisser plate theory presented by Hu Hai-chang, the governing equations were introduced into Hamilton system, and the differential equation set model of static bending and free vibration problems of moderately thick plate were presented respectively. The unitary model for the two problems was given after comparison. In the presented united forms, the Hamilton matrix H includes two zero block matrix in the diagonal place. For the homogeneous differential equation set, the characteristic roots were compared for the static bending and free vibration problems of moderately thick plate. Then the ordinary solutions of the homogeneous equations were obtained and compared. Thus the solution finding is rational and reasonable. The solving procedure follows a set of methodology,and the solving procedure can be extended to other problems.

Abstract:The structure of Lagrangian’s family formed of first integral and the existence conditions were restudied.The study shows that a Lagrangian’s family can be constructed in many sorts of ways.The new forms of the existence conditions of Lagrangian’s family were given.

Abstract:The variant Boussinesq equations were studied based on the multisymplectic theory in Hamilton space. The multisymplectic Preissmann method was reviewed,and a semiimplicit scheme with certain discrete conservation laws was constructed to solve the first order partial differential equations derived from the variant Boussinesq equations. The results of numerical experiment for soliton solution of the variant Boussinesq equations were obtained,which show that the multisymplectic Preissmann method is an efficient algorithm with excellent long time numerical behaviors.

Abstract:By using chaotic excitation and attractor geometric property analysis, a method to identify the joint damage was presented. A chaotic excitation signal was used to interrogate the structure, and the measured structural response attractor was reconstructed in state space. A new feature based on the attractor local variance was extracted and used to identify the damage. An experimental cantilevered beam for the joint damage identification was designed, and the joint damage conditions were quantified by varying the fastener preload. The approach was applied to detec five different joint damage conditions. The results indicate that this approach can be used to identify the joint damage and the feature is monotonic varying with the damage condition changes.

Abstract:Based on the Lyapunov-Krasovskii stability theory, a linear controller was proposed to achieve synchronization of a delayed Lorenz chaotic system. The presented control law is simple and easy to be implemented. To illustrate the effectiveness of the proposed control algorithm and complete the synchronous simulation, the digital circuit of the delayed Lorenz chaotic system was designed via DSP builder. Finally, simulation results were given to show the effectiveness of the proposed method.

Abstract:A class of two-degree-of-freedom multiple constraint mechanics model of the vibro-impact system was considered. According to the oscillator possible sticking situation, the explicit solution of every possible situation was worked out. Through the sticking motion’s necessary condition, we prove that the two oscillators won't appear sticking at the same time when the constraints are in different side. When constraints are located in the same side, by adjusting the parameters, the sticking may occur at the same time. That was called temporarily “motionless” situation. Finally, numerical calculation verified the cycle sticking motion and rising phenomena when the constraints are in different side and temporarily “motionless” situation when constraints are located in the same side. By numerical calculation, one can see that temporary "motionless" situation generally happens or ends by two vibrators successively entering or leaving sticking motion. It is not that the two oscillators are sticking or end at the same time.

Abstract:The coordination and cooperative control of networked multi agent systems has many significant applications in the engineering world. This paper investigated the impulsive consensus problem of multi-agent system with an active leader. It is assumed that only one agent of the network updates its state in the impulse manner based on its and the leader’s position at a series of discrete moments. By using tools from matrix theory, numerical analysis and the theory of impulsive differential equation, a simple yet generic criterion was then derived for consensus of the multi agent system. Consequently, computer numerical simulations verify and also visualize the theoretical results, which shows the impacts of the impulsive duration and impulsive strength on the convergence rate.

Abstract:To reduce shell vibration response caused by deck vibration, a grid sandwich structure with lattice grids was introduced as a new deck structure, according to the theory of impedance mismatch. The sandwich plate mounted on a cylindrical shell with end plates was studied, and the finite element software was used to simulate the sandwich plate’s vibration suppression performance. The structural parameters affecting the vibration suppression were discussed, and an experimental study was carried out. Both simulation results and experimental data show that the grid sandwich plate can effectively reduce the vibration response of cylindrical shell. The vibration suppression in the high-frequency is excellent. The impact of grid structural parameters on the vibration suppression is complex, but using damping material as sandwich grid upper panel can improve the vibration suppression.

Abstract:Coarse and short fiber ends protruding above fabric surface mainly contribute to prickiness sensation of nexttoskin clothing, and the delectability of this sensation is usually based the justification on the critical buckling force of single fiber end as a fixedhinged slender rod under axial compression. The assumption that a fiber end prickling human skin is fixedhinged, however, can be too simplified to describe the real constraint conditions, both the end prickling human skin and the other end held in fabric. To clarify the role of different constraint conditions in the bending mechanical behavior of single fiber protruding fabric surface and prickling human skin, a coupling fiberskin model was established to simulate the prickling indentation into skin, where the end against human skin is constrainted by fiberskin friction and the other end held in fabric surface can rotate with a linear elastic stiffness,and then a parametric analysis on friction coefficient and rotation stiffness was performed. The results show that the elasticconstraint fiber end can subject to a higher axial compression force than the psychophysical threshold of perceived prickliness sensation, and most of published prickliness phenomenon can be explained on the basis of the established fiberskin model with friction and elastic constraints.

Abstract:From the study of the cardiac ganglion of the lobster model, this paper made a detailed analysis on the complex bursting produced in it from the perspective of nonlinear dynamics. By discussing the roles of electrophysiological parameters under different cases, the rich dynamical properties are contained in the complex bursting of the cardiac ganglion of the lobster model, such as the InterSpike Intervals(ISIs) is period adding bifurcation and period doubling bifurcation. From the model results, we can get a further understanding of the rich firing patterns and rhythm coding, which are contained in the burst firing of the cardiac ganglion of the lobster.

Abstract:The characteristics of flap vibration of a wind turbine blade with large deflection were studied. The governing equation of the vibration under unsteady aerodynamic loads, whose expressions were derived from the Greenberg expressions, was established by applying the Hamiltonian principle. The RayleighRitz method was used to calculate frequencies and mode functions. Based on these mode functions, the partial differential equation governing the vibration was discreted by using the Galerkin’s method. The displacement was resolved to static displacement and dynamic displacement, and the equations of the static and dynamic displacement were obtained. The effects of the inflow ration to the static displacement and the aerodynamic damping were discussed. The dynamic response was analyzed by using the nonlineardynamical tools. The results show: 1) that the static displacement rises with the inflow ratio, and it reaches the limit at the blade tip; 2) that the vibration is a harmonic motion for small inflow ratio, and it becomes a quasiharmonic motion when the inflow ratio is big.

Abstract:This paper studied the design method of the LQG selftuning controller to suppress the flutter of a wing. The flexible wing model with a single trailingedge control surface was used in this study. The online identification was used to obtain the timevarying parameters of the system, and the Kalman filter was used to estimate the states of the system. Then, the control law was determined by solving a set of discretetime algebraic Riccati equations. All the developed algorithms were implemented on the Simulink platform. The simulation results show that the developed controller is effective and robust.

Abstract:In terms of Unmanned Powered Parafoil Aircraft（UPPA）always flight in the low level sky and on top of the city’s hight rise.It often gets hight frequency disturb by all kinds of wind.It’s velocity and course angle or wind all affect the response characteristic of UPPA gesture. Then it will induce controlled rules be unsuitable with switch parameters. The PID algorithms can not reach satisfactory controlled effect. A fuzzy controller for UPPA gesture based on RBF networks and genetic algorithms is designed. A new method is also proposed for the self-tuning of scaling factors and genetic algorithm is employed to optimize the parameters used in tuning process in order to keep good controlling performance in case of time varying and uncertainties. Finally, with the nonlinear UPPA model of a mariner level vessel, simulation tests are carried out and results are satisfactory.

Abstract:In order to study the effect of vertical ambient vibration on coupling vibration of bodyvehicleroad system, the human body was simplified as the parallel dynamic model, the vehicle was simplified as the sevenfreedom vibrating model, and the road was supposed as the Euler Beam on the Kelvin base. And then based on the interaction force between the road and the vehicle, the dynamic functions of the vehicleroad coupled system were derived. The functions were solved with the Newmark method. The riding comfort of the vehicle was appraised with the RMS of the body vibrating acceleration. The effects of the seismic wave frequency and its amplitude on the system vibration were analyzed, and the vibrating comfort of the vehicle and human physiological responses were discussed. The numeric analysis results indicate that the vertical ambient vibration aggravates the vibration of the bodyvehicleroad coupled system, and also enlarges the value of the vibrating comfort of the vehicle; the seismic wave frequency and its amplitude have great effect on the vibrating comfort of the vehicle.

Abstract:《动力学与控制学报》第三届编委会会议于2012年4月14日在湖南大学集贤宾馆召开.与会人员有编委21人、编辑部成员3人及相关专家.会议由副主编张伟教授主持.会议的主要议程为：中国力学学会动力学与控制专业委员会主任、副主编徐鉴教授致开幕辞；湖南大学校长、主编赵跃宇教授作“《动力学与控制学报》编委会工作报告”；第一、二届编委会副主编梅凤翔教授作“关于《动力学与控制学报》历史回顾与发展”的重要讲话；接着与会代表就《动力学与控制学报》进一步提高刊物的学术质量和社会影响等进行讨论；最后，赵跃宇教授还作了总结发言.