Robust Adaptive Fuzzy Control of Nonlinear Systems

Abstract

In this paper, an adaptive Fuzzy Fast Terminal Synergetic Controller (FFSC) for a certain class of SISO unknown nonlinear dynamic systems is proposed, that uses the concept of terminal attractor design, adaptive fuzzy synergetic control scheme, and Lyapunov synthesis approach. In contrast to the existing adaptive fuzzy synergetic control design, where the fuzzy systems are used to approximate the unknown system functions while the synergetic control guarantees robustness and achieves the asymptotic stability of the closed-loop system, in our technique both the continuous synergetic control law and the fuzzy approximator are derived to ensure finite-time convergence. Lyapunov conditions for finite-time stability and accuracy proofs in mathematics are presented to prove that the proposed adaptive scheme can achieve finite-time stable tracking of reference input and guarantee of the bonded system signals. Simulation results illustrate the design procedures and demonstrate the performance of the proposed controller.

Pantograph Catenary Contact Force Regulation Based on Modified Takagi-Sugeno Fuzzy Models

“…Additionally, the numerator and denominator coefficients are calculated so that the total closed-loop system acts as a linear system. Further, the notion above is expanded for continuous systems in the suggested method in [14]. The closed-loop T-S fuzzy control system acts as a polytope of linear systems based on the recently developed technique.…”

“…The local PI controller parameters can be finally chosen by using the proposed robust D-partition and some optimal performance criterions. By using the modified fuzzy T-S model [14][15], the i-th fuzzy IF-THEN rule for the describing plant is presented as follows:…”

“…Many control algorithms have been developed (simple PI controllers [5], robust controllers [6], adaptive controllers [7], backstepping controllers [8], predictive model controllers [9], intelligent controllers [10][11][12], and fuzzy controllers [13]) for producing adequate uplift force to regulate the fluctuation of the contact force. To manage the oscillations brought on by the unpredictable stiffness and to regulate the contact force taken into account as a pre-specified reference value, an intelligent contact force regulator, including MZL algorithms [14][15], is given in [10]. The vibration of the contact force caused by the catenary's time-varying stiffness can be successfully suppressed, and the comparative simulation results demonstrate that the suggested method is more effective than the previous fuzzy algorithms.…”

Improved Torque Ripple of Switched Reluctance Motors using Sliding Mode Control for Electric Vehicles

“…The problem is that because of structural deformations and magnetic torque harmonics that cause the stator and rotor to interact, this process also generates vibration and noise. As a result, noise is produced, and the motor's lifetime is shortened by the interactions and oscillations that alter the torque or torque ripple [7][8][9][10][11][12][13]. This SRM torque ripple limits the possibility of their direct-drive applications in the industry.…”

Dynamic Analysis and Design of an SMCNN of a 6-DOF Parallel Mechanisms using Translation Driver Motor

“…Up to now, the control of the nonlinear system with uncertain parameters is still a difficult task, so the feedback control methods combined with the Lyapunov stabilization method [3][4][5] and received much attention. One of the proposed methods for a non-linear control system that attracts many researchers are back-stepping, Fuzzy-PI with genetic control algorithms and robust adaptive fuzzy control to meet the motion requirement [6] and [10][11].…”