Ropeway roller batteries dynamics: Modeling, identification, and full-scale validation

Abstract

A parametric mechanical model based on a Lagrangian formulation is here proposed to predict the dynamic response of roller batteries during the vehicles transit across the so-called compression towers in ropeways transportation systems. The model describes the dynamic interaction between the ropeway substructures starting from the modes and frequencies of the system to the forced dynamic response caused by the vehicles transit. The analytical model is corroborated and validated via an extensive experimental campaign devoted to the dynamic characterization of the roller battery system. The data acquired on site via a custom-design sensor network allowed to identify the frequencies and damping ratios by employing the Frequency Domain Decomposition (FDD) method. The high fidelity modeling and the system identification procedure are discussed.

Nonlinear vibration absorbers for ropeway roller batteries control

“…The mechanical system here investigated is based on the parametric nonlinear formulation first proposed in [12]. The model takes into account the multibody assembly consisting of four interacting mechanical subsystems, namely, the elastic cable traveling along the ropeway line, the vehicle attached to the cable, the roller battery, and the hoisting beam connected to the tower (see Fig.…”

“…The latter is modeled as an equivalent Euler-Bernoulli cantilever beam whose length L b , bending stiffness E b I b , and mass ρA b are determined so as to reflect the static and dynamic flexural behavior of the actual elastic structure connecting the roller battery to the tower. Although the cable is the moving structural element of the system (i.e., the vehicle is propelled by the moving cable itself), the same modeling approach experimentally validated in [12] is here adopted. Thus the vehicle is modeled as a visco-elastic pendulum traveling across a stationary cable segment modeled as a prestressed string.…”

“…The values of the geometric and mechanical parameters presented in Eqs. ( 1) and ( 2) can be found in [12].…”

“…By taking into account the nonlinear parametric model of ropeways compression roller batteries which was theoretically proposed and experimentally validated by the authors in [11,12], a number of vibration absorbers is deployed on the different stages of the roller battery system to mitigate the accelerations due to the vehicle transit. The three stages of the roller battery system are depicted in Fig.…”

Nonlinear Dynamic Response of Ropeway Roller Batteries via an Asymptotic Approach

“…On the other hand, little attention was paid to the study of the local dynamic interactions taking place between the vehicle, the cable, the roller battery, and the supporting tower; few works have investigated these aspects [11]. A nonlinear model of compression roller batteries, used as a starting point for the studies proposed in the present work, was first developed in [12,13]. In such works, experimental tests were also carried out on an operating ropeway, so as to identify the modal characteristics of the system by adopting the Enhanced Frequency Domain Decomposition method, and to validate the analytical model by comparing the experimental dynamic responses with the numerical simulations.…”