A Comparative Analysis of High-Accuracy Black-Box and Grey-Box Models of MR-Dampers for Vehicles Control

Abstract

The topic of this paper is the identification of a high-precision model for Magneto-Rheological (MR) dampers. A semi-active MR-damper can be seen as a non-linear system, where the inputs are the stroke-velocity and the command current; the current is the control input which modulates at high-bandwidth the damping characteristic through the variation of a magnetic field. The output is the force delivered by the damper. Among the broad set of applications where MR-dampers can be used, this work mainly focuses on MR-dampers for the control of vehicle dynamics (trains, road vehicles, tractors, etc.). High-precision models of MR dampers can be designed using two different model classes: gray-box models (also called semi-physical models) and black-box models. Both approaches are considered in this work. All the main problems and issues of the identification procedure are presented and discussed: experiment design, signal pre-processing, model-structure and performance-index selection, optimization and parameter estimation, model validation and software-implementation. State-of-the-art and innovative model structures are considered for analysis. The result provides a broad and detailed overview on approaches, tools, issues, and design choices for the development of MR-damper models.