Robust ℋ∞-Fuzzy Logic Control for Enhanced Tracking Performance of a Wheeled Mobile Robot in the Presence of Uncertain Nonlinear Perturbations

Abstract

<jats:p>Motion control involving DC motors requires a closed-loop system with a suitable compensator if tracking performance with high precision is desired. In the case where structural model errors of the motors are more dominating than the effects from noise disturbances, accurate system modelling will be a considerable aid in synthesizing the compensator. The focus of this paper is on enhancing the tracking performance of a wheeled mobile robot (WMR), which is driven by two DC motors that are subject to model parametric uncertainties and uncertain deadzones. For the system at hand, the uncertain nonlinear perturbations are greatly induced by the time-varying power supply, followed by behaviour of motion and speed. In this work, the system is firstly modelled, where correlations between the model parameters and different input datasets as well as voltage supply are obtained via polynomial regressions. A robust H ∞ -fuzzy logic approach is then proposed to treat the issues due to the aforementioned perturbations. Via the proposed strategy, the H ∞ controller and the fuzzy logic (FL) compensator work in tandem to ensure the control law is robust against the model uncertainties. The proposed technique was validated via several real-time experiments, which showed that the speed and path tracking performance can be considerably enhanced when compared with the results via the H ∞ controller alone, and the H ∞ with the FL compensator, but without the presence of the robust control law.</jats:p>

An Approach on Velocity and Stability Control of a Two-Wheeled Robotic Wheelchair

“…Equation (19) proves that the first-layer sliding surfaces σ 1 and σ 2 are also asymptotically stable.…”

“…One example is computed torque control based on nonlinear feedback and the assumption that the exact dynamic model of the system is known [17]. For the cases where the system dynamics cannot be accurately modelled, or there are external disturbances, H ∞ which is robust against disturbances can be used [18,19]. Nonlinear H ∞ control is developed based on the Hamilton-Jacobi-Bellman-Isaacs (HJBI) equation which is hard to solve in real-time though [20].…”

Review and performance evaluation of path tracking controllers of autonomous vehicles

“…However, in this case, a combination of the kinematic and dynamic model is used. Another integrated fuzzy logic and ‐based controller is reported in [130], where parametric uncertainties of the DC motor of the vehicle is considered.…”

Wind Field Disturbance Analysis and Flight Control System Design for a Novel Tilt-Rotor UAV

“…Therefore, there are problems of system model uncertainty and environmental interference to be considered in the control system of Tilt-rotor UAV. In this paper, a control method based on H  robust control with mixed sensitivity is proposed, which could bring better interference suppression ability and performance tracking ability to the system [41]- [43].…”