Takagi-Sugeno Fuzzy Model of a One-Half Semiactive Vehicle Suspension: Lateral Approach

Abstract

This work presents a novel semiactive model of a one-half lateral vehicle suspension. The contribution of this research is the inclusion of actuator dynamics (two magnetorheological nonlinear dampers) in the modelling, which means that more realistic outcomes will be obtained, because, in real life, actuators have physical limitations. Takagi-Sugeno (T-S) fuzzy approach is applied to a four-degree-of-freedom (4-DOF) lateral one-half vehicle suspension. The system has two magnetorheological (MR) dampers, whose numerical values come from a real characterization. T-S allows handling suspension’s components and actuator’s nonlinearities (hysteresis, saturation, and viscoplasticity) by means of a set of linear subsystems interconnected via fuzzy membership functions. Due to their linearity, each subsystem can be handled with the very well-known control theory, for example, stability and performance indexes (this is an advantage of the T-S approach). To the best of authors’ knowledge, reported work does not include the aforementioned nonlinearities in the modelling. The generated model is validated via a case of study with simulation results. This research is paramount because it introduces a more accurate (the actuator dynamics, a complex nonlinear subsystem) model that could be applied to one-half vehicle suspension control purposes. Suspension systems are extremely important for passenger comfort and stability in ground vehicles.

Disturbance Rejection in a One‐Half Semiactive Vehicle Suspension by means of a Fuzzy-H∞ Controller

“…e whole system is fully expressed with the following Takagi-Sugeno fuzzy model where each nonlinear term was represented by two linear systems interconnected via fuzzy membership functions. Further explanations about the MR damper's composition and its behaviour are extensively explained in [4], whereas the complete development of the half-vehicle semiactive suspension model with the MR dampers is found in [25]:…”

“…Even though the first approach in control design was a static state feedback controller (SSFC) to guarantee stability in closed loop, there were not enough degrees of freedom to design based on performance criteria; hence, a fuzzy-H ∞ controller became an attractive option (the closedloop diagram is presented in Figure 6). Shock and Vibration 5 membership functions [25]. e applied closed loop is as follows.…”

“…Simulation results based on real data support the theoretical work in previous sections. e MR damper Bouc-Wen model numerical data were taken from a realistic damper's characterization [47], whereas the rest of parameters were adopted from [25]. MR dampers do not respond instantaneously to current changes; they are modelled as firstorder systems with a time constant η � 0.052 ms [4].…”

“…is work considers the reported 4-DOF one-half vehicle suspension lateral model in the study of Félix-Herrán et al [25] and the fuzzy-H ∞ controller for a one-quarter vehicle developed in the study of Félix-Herrán et al [26], and it includes the disturbance phase angle and computes a fuzzy-H ∞ controller that complies with a set of performance criteria. is article is organized as follows: Section 2 states the performance criteria, and Section 3 provides a brief review of the control-oriented one-half suspension model applied herein.…”