Interval type-2 sliding mode fuzzy controller with a time-varying sliding surface

2017 ◽  
Author(s):  
Osman Eray ◽  
Sezai Tokat
Keyword(s):  
Fuzzy Controller ◽  
Sliding Mode ◽  
Time Varying ◽  
Sliding Surface ◽  
Interval Type

Adaptive interval type-2 fuzzy controller for nonlinear networked Wiener systems subject to packet dropout and time-varying delay

2021 ◽  
Author(s):  
Ahmad M. El-Nagar ◽  
Tarek R. Khalifa ◽  
Mohamed A. El-Brawany ◽  
Mohammad El-Bardini ◽  
Essam A.G. El-Araby
Keyword(s):  
Fuzzy Controller ◽  
Packet Dropout ◽  
Time Varying ◽  
Time Varying Delay ◽  
Wiener Systems ◽  
Interval Type ◽  
Varying Delay

scholarly journals Interval Type-2 Fuzzy Observers Applied in Biodegradation

2021 ◽  
Vol 1 (2) ◽  
pp. 145-158
Author(s):  
Marco Antonio Márquez-Vera ◽  
Andrea Rodríguez-Romero ◽  
Carlos Antonio Márquez-Vera ◽  
Karla Refugio Ramos-Téllez
Keyword(s):  
Fuzzy Inference ◽  
Fuzzy Controller ◽  
Sliding Mode ◽  
The Other ◽  
Liquid Volume ◽  
Estimation Errors ◽  
Loop Control ◽  
Fuzzy Observer ◽  
Interval Type

There exist processes difficult to control because of the lack of inline sensors, as occurs in biotechnology engineering. Commonly the sensor is expensive, damaged, or even they do not exist.  It is important to build an observer to have an approximation of the process output to have a closed-loop control. The biotechnological processes are nonlinear, thus in this work is proposed a fuzzy observer to endure nonlinearities. To improve the results reported in the literature, type-2 fuzzy logic was used to justify the membership functions used. The observer's gains were computed via LMIs to guarantee the observer's stability.  To facilitate the fuzzy inference computation, interval type-2 fuzzy sets were implemented. The results obtained with the interval type-2 fuzzy observer were compared with a similar technique that uses a fuzzy sliding mode observer; this new approach gives better results obtaining an error 60% lower than the obtained with the other technique. They were designed three observers that work ensemble via a fuzzy relation. The best approximation was to estimate the intermediate concentration. It is important to know this variable because this sub-product was also toxic. It was concluding that by using the oxygen concentration and the liquid volume inside the reactor, the other concentrations were estimated. Finally, this result helps to design a fuzzy controller by using the estimated state. Using this approach, the estimation errors for the phenol and biomass concentrations were 49.26% and 21.27% lower than by using sliding modes.

Backstepping Sliding Mode Controller Improved with Interval Type-2 Fuzzy Logic Applied to the Dual Star Induction Motor

2019 ◽  
Vol 18 (02) ◽  
pp. 1950012
Author(s):  
Hilal Rahali ◽  
Samir Zeghlache ◽  
Loutfi Benyettou ◽  
Leila Benalia
Keyword(s):  
Fuzzy Controller ◽  
Sliding Mode ◽  
Reference Signal ◽  
Induction Machine ◽  
Angular Speed ◽  
Sliding Mode Controller ◽  
Chattering Effect ◽  
The Stability ◽  
Interval Type

This paper proposes Interval type-2 Fuzzy sliding mode controller based on Backstepping (IT2FBSMC), to control the speed of a dual star induction machine (DSIM), in order to get a robust performance machine. An appropriate control strategy based on the coupling of three methods (Backstepping, sliding mode and type-2 Fuzzy controller) is used to build a robust controller used to approximate the discontinuous control eliminating the chattering phenomenon and guaranteeing the stability of the machine. Moreover, it forces the rotor angular speed to follow a desired reference signal. The simulation results obtained using Matlab/Simulink behavior are presented and discussed. The obtained results show that the controller can greatly alleviate the chattering effect and enhance the robustness of control systems with high accuracy.

scholarly journals Hybrid robust controller based on interval type 2 fuzzy neural network and higher order sliding mode for robotic manipulators

2019 ◽  
Vol 32 (02) ◽  
pp. 106-125
Author(s):  
S. Mohammadrezaei Nodeh ◽  
M. H. Ghasemi ◽  
H.R. Mohammadi Daniali
Keyword(s):  
Neural Network ◽  
Fuzzy Controller ◽  
Sliding Mode ◽  
Self Regulation ◽  
Higher Order ◽  
Central Type ◽  
The Neural Network ◽  
Fuzzy Neural ◽  
Interval Type

Industrial arms should be able to perform their duties in environments where unpredictable conditions and perturbations are present. In this paper, controlling a robotic manipulator is intended under significant external perturbations and parametric uncertainties. Type-2 fuzzy logic is an appropriate choice in the face of uncertain environments, for various reasons, including utilizing fuzzy membership functions. Also, using the neural network (NN) can increase robustness of the controller. Although neural network does not basically need to build its type-2 fuzzy rules, the initial rules based on sliding surface of higher order sliding mode controller (HOSMC) can improve the system's performance. In addition, self-regulation feature of the controller, which is based on the existence of the neural network in the central type-2 fuzzy controller block, increases the robustness of the method even more. Effective performance of the proposed controller (IT2FNN-HOSMC) is shown under various perturbations in numerical simulations.

Adaptive sliding mode fault tolerant control for interval Type-2 fuzzy singular fractional-order systems

2021 ◽  
pp. 107754632098018
Author(s):  
Xuefeng Zhang ◽  
Wenkai Huang
Keyword(s):  
Fractional Order ◽  
Fault Tolerant ◽  
Sliding Mode ◽  
Fault Tolerant Control ◽  
Fractional Order Systems ◽  
Sliding Surface ◽  
Actuator Faults ◽  
Interval Type ◽  
Fault Information

This article proposes an integral sliding mode control scheme for a class of uncertain nonlinear singular fractional-order systems subject to actuator faults. The interval type-2 Takagi–Sugeno model is used to represent the singular fractional-order systems. First, a novel integral sliding surface is constructed. A sufficient condition is given in terms of linear matrix inequalities which guarantees the admissibility and the robustness of the singular fractional-order systems against actuator faults. Then, aiming at the fault information which is difficult to get in the practical application, an adaptive estimation of fault information is proposed to update the sliding mode controller. A sliding mode fault tolerant control law is designed to make the singular fractional-order systems reach the sliding surface in a finite time. At last, the applicability and effectiveness of the proposed method is illustrated by a numerical simulation example.

scholarly journals New Time-Varying Sliding Surface for Switching Type Quasi-Sliding Mode Control

Energies ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3811
Author(s):  
Katarzyna Adamiak ◽  
Andrzej Bartoszewicz
Keyword(s):  
Sliding Mode Control ◽  
Continuous Time ◽  
Sliding Mode ◽  
Representative Point ◽  
Time Varying ◽  
Sliding Surface ◽  
External Disturbances ◽  
Mode Control ◽  
Switching Type ◽  
Time Systems

This study considers the problem of energetical efficiency in switching type sliding mode control of discrete-time systems. The aim of this work is to reduce the quasi-sliding mode band-width and, as follows, the necessary control input, through an application of a new type of time-varying sliding hyperplane in quasi-sliding mode control of sampled time systems. Although time-varying sliding hyperplanes are well known to provide insensitivity to matched external disturbances and uncertainties of the model in the whole range of motion for continuous-time systems, their application in the discrete-time case has never been studied in detail. Therefore, this paper proposes a sliding surface, which crosses the system’s representative point at the initial step and then shifts in the state space according to the pre-generated demand profile of the sliding variable. Next, a controller for a real perturbed plant is designed so that it drives the system’s representative point to its reference position on the sliding plane in each step. Therefore, the impact of external disturbances on the system’s trajectory is minimized, which leads to a reduction of the necessary control effort. Moreover, thanks to a new reaching law applied in the reference profile generator, the sliding surface shift in each step is strictly limited and a switching type of motion occurs. Finally, under the assumption of boundedness and smoothness of continuous-time disturbance, a compensation scheme is added. It is proved that this control strategy reduces the quasi-sliding mode band-width from O(T) to O(T3) order from the very beginning of the regulation process. Moreover, it is shown that the maximum state variable errors become of O(T3) order as well. These achievements directly reduce the energy consumption in the closed-loop system, which is nowadays one of the crucial factors in control engineering.

Sign in / Sign up

Export Citation Format

Share Document