On dynamic analysis and control of an elevator system using polynomial chaos and Karhunen-Loève approaches

The paper deals with the quantification of uncertainties in an elevator system, subjected to lateral vibration induced by the car guide rail irregularities, with and without a feedback control system. A mathematical model for the elevator system is derived, and a stochastic model for the rail profile irregularities is constructed. This model of uncertainties describes the rail profile as a random field, which is represented by means of Karhunen-Loève expansion. Polynomial chaos is employed to compute the propagation of uncertainties through the stochastic model, in order to evaluate the disturbance rejection properties and robustness of the closed-loop system.