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This article explores the synchronization, stability and motion characteristics of the generalized dynamical model with two rigid frames (RFs) driven by two groups (even number) of coaxial rotating exciters. In light of this system’s generalized coordinates, we use Lagrange’s equations to derive the generalized differential equation of motion. The responses of absolute and relative motion of the generalized system are obtained using the transfer function method. The synchronization and stability criteria of multiple exciters are derived using the average method and Hamilton’s theory, respectively. Taking a dynamical model driven by two pairs of exciters as an example, the localized studies of generalized results are carried out. The stable synchronous solutions for phase differences and excitation frequency, the stability ability coefficient curves and the response curves are graphically presented considering the effect of two crucial dimensionless parameters on the stable synchronous states. The simulation results of the specific system are obtained using the fourth-order Runge-Kutta algorithms and compared with the numerical qualitative analysis results to reveal the high consistency between them and clarify the used methods’ effectiveness. The strength of this work stems from its use in the field of high power and large scale self-synchronization vibrating machines.

The linear and nonlinear dynamics of a bolted cylindrical shell under a point excitation were experimentally investigated. The tests have been carried out through methods of the hammer test and sweeping frequency test. This paper aims to discover the effect of bolt joints on shell vibration, including the effects of bolt number, tightening torque, and excitation levels. The natural characteristics were analyzed by utilizing natural frequency and mode shapes. The nonlinear dynamic characteristics were analyzed through amplitude-frequency curves. The resonance frequency, resonance amplitude, and damping ratio under different tightening torques and excitation levels were investigated. Results show that: the number of bolts can not only change the value and order of the natural frequencies but also the shapes of the mode; The low tightening torque and larger excitation levels strongly lead to more complex nonlinear dynamics of shell structures.