Controlling Chaos in Rotating Systems Applying the Ott-Grebogi-Yorke Control Method in Active Sliding Bearing Configurations

Ioannis Polyzos and Athanasios Chasalevris
J. Comput. Nonlinear Dynam. Sep 2025, 20(9): 091003
https://doi.org/10.1115/1.4068698

In rotating systems where a shaft is mounted on journal bearings, chaotic dynamic response may occur under specific design and operating conditions. Although chaos does not necessarily prevent the operation of rotating machines, it may result in higher frictional power loss and temperature rise in the bearings, compared to operation with periodic or quasi-periodic responses; it is also likely to compromise the integrity of the system when whirling orbits evolve to a large extent. A rotor-bearing system consisting of a rigid rotor mounted on two journal bearings is used to produce chaotic dynamics, which are detected and verified using numerical tools. This study uses sliding bearings with active geometry, that serves as the control input, and implements the Ott-Grebogi-Yorke (OGY) discrete-time control method, to convert chaotic oscillations to periodic. It is found that the OGY method can control the chaotic response and produce periodic motions of desired periodicity with minimal control effort. This method proves robust to measurement errors and noise, actuation errors as well as model uncertainties in oil viscosity and bearing radial clearance. Performance was further enhanced with the use of a Model Predictive Control (MPC) assisted OGY strategy. The results create potential for smooth periodic motions in high-speed rotating systems.