Dynamic analysis of umbilical cables for maglev vibration isolation systems

Umbilical cables are the only paths that transmit vibration from the base to the upper platform in a maglev vibration isolation platform. The geometry properties and the vibration transmission characteristics of umbilical cables are crucial for the isolation performance of maglev vibration isolation platforms. The dynamic model of umbilical cables is studied comprehensively based on the nonlinear mechanics of a thin elastic rod, and the model is solved according to a differential quadrature method. A case about a cantilever cable is solved to verify the accuracy, efficiency, and convergence of the solution. The method to obtain an equivalent dynamic model of umbilical cables is analyzed, and the relationship between the excitation parameters and the disturbing forces/moments is obtained, which can be applied in the overall dynamic analysis of maglev vibration isolation systems. Experiments are carried out to verify the dynamic model, the numerical solution, and the equivalent dynamic model. To understand the applicability of the equivalent dynamic model, disturbing forces and moments caused by different frequencies, different amplitudes, and different initial configurations are compared; and the transmission characteristics of umbilical cables are obtained. The research has an important significance on the dynamic analysis of umbilical cables for maglev vibration isolation systems, and the method in establishing an equivalent dynamic model of umbilical cables is applicable.