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In this paper, the synchronous control method for multi-motor coupled with pendulum in a vibration system is introduced. The dynamic model of three eccentric rotors (ERs) driven by three motors rotating in the same direction in the system is firstly established. However, to obtain elliptical trajectory, the ideal synchronization motion (zero-phase difference) of the three ERs should be satisfied. Therefore, the synchronous control strategy for the proposed system is described. Then, the exponential reaching law sliding mode control (ERL-SMC) with adjacent cross-coupling control structure is applied to design the controllers of rotational velocity error and synchronization error. Meanwhile, the stability performance of the controllers is demonstrated by Lyapunov theory and Hurwitz condition. Furthermore, the adaptive method is applied to the ERL-SMC to improve the control accuracy of the system. Finally, computer simulation based on Matlab/Simulink is implemented to validate the effectiveness of the control system; besides, the impact of parameter perturbations in the control system are considered to verification the robustness of controllers related to the velocity and synchronization.

The general issues of the development of an optimal circuit diagram of a vibration system and determination of the parameters of this circuit providing an extreme criterion of optimality are considered. The object of research is technical machines and technological media, which are considered as a system subordinated to a single vibration process. By technical machines, vibration machines adopted in the work for the implementation of compaction processes are adopted. Technological media adopted two-phase dispersed media used for compaction. Concrete mixes and soils are accepted by such media. Reducing energy costs, a high level and speed of energy transfer to the process are the main factors in creating optimal schemes of vibration systems. One of the most problematic places in solving this approach is the lack of a generally accepted model for the interaction of the working bodies of machines with the processing medium. Existing studies are based on the separate determination of the parameters of machines and media. Such methods are characterized by significant energy costs and a long duration of the process. The proposed approach based on the harmonization of the forces of machines and media arising in the vibration process, has significantly reduced energy costs. The work also obtained a new synergistic effect of the system. This is due to the fact that the proposed method for creating the optimal circuit has a number of features. So, in the course of the study, the modes of combining the elastic-inertial forces of the subsystems in a single system are used. Particular implementation of subresonance and superresonance modes are determined. Thanks to this, it is possible to maximize the effectiveness of vibration systems not only in new design solutions, but also in the targeted use of the internal properties of the integrated system. Compared with similar well-known vibrating machines, energy costs are reduced by 50 %. The proposed methodology for developing organizational principles for the formation of the optimal scheme and parameters is used in the design of vibration systems for vibration and vibration-shock modes of compaction of building mixtures.

To solve the limitation of vibration synchronization, this paper investigates the dynamics of a vibration system driven by three homodromy eccentric rotors (ERs) using control synchronization. According to the synchronous condition and the stability condition, the changes of the phase differences of the three-ERs system and the two-third ERs system are obtained. Based on the electromechanical mathematic model of the vibration system and the master-slave control strategy, the synchronous target that three ERs achieve the same phase motion is converted into velocity and phase tracking of ERs. Considering the coupling characteristic of the self-adjusting of the system in the state of vibration synchronization, the velocity and phase controllers are designed by employing discrete-time sliding mode control. An experimental system for control synchronization is designed, including hardware composition and software programming. For the feedback signal used to match control targets, a method of calculating velocity and the phase difference is proposed from engineering. Recording the rotational velocities, phase differences, and system response, three group experiments with different control schemes are achieved. According to the experimental data, the coupling characteristic of the vibration system adopting control synchronization is analyzed, which can provide the basis for designing vibration machines using control synchronization.

Rubber materials are extensively utilized for vibration mitigation. Creep is one of the most important physical properties in rubber engineering applications, which may induce failure issues. The purpose of this paper is to provide an engineering approach to evaluate creep performance of rubber systems. Using a combination of hyper-elastic strain energy potential and time-dependent creep damage function, new creep constitutive models were developed. Three different time-decay creep functions were provided and compared. The developed constitutive model was incorporated with finite element analysis by user subroutine and its engineering potential for predicting the creep response of rubber vibration devices was validated. Quasi-static and creep experiments were conducted to verify numerical solutions. The time-dependent, temperature-related, and loading-induced creep behaviors (e.g., stress distribution, creep rate, and creep degree) were explored. Additionally, the time&ndash, temperature superposition principle was shown. The present work may enlighten the understanding of the creep mechanism of rubbers and provide a theoretical basis for engineering applications.

Simple adaptive control (SAC) is a control method that maintains control performance despite perturbations of a plant. However, there is a problem in that the vibratory output occurs in the transient response when SAC is applied to a vibration system which includes anti-resonance modes. The occurrence of the output depends on the structure of SAC and the output is caused by the vibratory input corresponding to the anti-resonance frequency. In order to overcome the problem, a method using an appropriate parallel feedforward compensator (PFC) is proposed. In the proposed method, an effective PFC is designed such that the gain of an augmented system is matched to that of a desired model under the ASPR condition of the augmented system. A design problem is described by LMI/BMI conditions. The problem using LMI/BMI conditions is solved by an iterative procedure. However, the leading coefficient of the PFC must be given a priori in order to guarantee the ASPR property, which provides some restrictions for applications of the proposed method. In the present paper, an improved method to overcome the abovementioned restrictions is proposed using the stability theorem of the descriptor system. The effectiveness of the proposed method is verified through numerical simulations and experiments., Article, Mechanical Engineering Journal. 2(3):14-00547 (2015)

This paper shows the developing process of an anti-vibration system, from its conception up to the construction of a experimental prototype. Special features and constraints that must be considered are specified, including a description and theoretical foundation of the working principle, a geometrical proposal and a component selection process, in order to ensure the effective operation of the system complying required specifications. Finally, the combination of these elements are used to design and build an experimental prototype capable to simulate the behavior of an anti-vibration system for ensuring the safe transfer and reliable operation of mammography equipment on board of a mobile medical unit.

MEMS gyroscope performs as a sort of sensor to detect angular velocity, with diverse applications in engineering including vehicle and intelligent traffic etc. A balanced vibration of driving module excited by electrostatic driving signal is the base MEMS gyroscope's performance. In order to analyze the linear property of vibration in MEMS Gyroscope, a method of computer vision measuring is applied with the help of high-speed vidicon to obtain video of linear vibration of driving module in gyroscope, under the driving voltage signal of inherent frequency and amplitude linearly increasing. By means of image processing, target identifying, and motion parameter extracting from the obtained video, vibration curve with time variation is acquired. And then, linearity of this vibration system can be analyzed by focusing on the amplitude value of vibration responding to the amplitude variation of driving voltage signal.