Stefan Preitl

6603196898

Publications - 5

Stability analysis and design of a class of MIMO fuzzy control systems

R. C. Pozna Marius L. Tomescu E. M. Petriu Radu Emil Precup Stefan Preitl János Fodor

Publication Name: Journal of Intelligent and Fuzzy Systems

Publication Date: 2013-07-18

Volume: 25

Issue: 1

Page Range: 145-155

Description:

This paper presents a new stability analysis method dedicated to a class of fuzzy control systems (FCSs) controlling multi input-multi output (MIMO) nonlinear processes by means of Takagi-Sugeno-Kang fuzzy logic controllers (FLCs). The stability analysis of the FCSs is carried out using LaSalle's global invariant set theorem by the separate stability analysis of each fuzzy rule in MIMO fuzzy control systems. Therefore the complexity of the stability analysis is reduced and the adding of new fuzzy rules can be conducted easily; this modification of FLC structure requires the fulfillment of only one of the conditions of the stability analysis theorem suggested in this paper. Another advantage of the stability analysis approach proposed in this paper is that the derivative of the Lyapunov function candidate must be only negative semi-definite in comparison with Lyapunov's stability theorem where it must be negative definite. The conservativeness of stability conditions is thus reduced, and this enables the convenient design of FLCs. The applicability and efficiency of the theoretical results are illustrated by numerical simulations for a representative MIMO process which deals with the level control in a three spherical tank system. © 2013-IOS Press and the authors. All rights reserved.

Open Access: Yes

DOI: 10.3233/IFS-2012-0621

Experimental results of evolving Takagi - Sugeno fuzzy models for a nonlinear benchmark

R. C. Pozna Mircea Bogdan Rǎdac Claudia Adina Dragos Horatiu Ioan Filip Radu Emil Precup Stefan Preitl

Publication Name: 3rd IEEE International Conference on Cognitive Infocommunications Coginfocom 2012 Proceedings

Publication Date: 2012-12-01

Volume: Unknown

Issue: Unknown

Page Range: 567-572

Description:

The paper offers evolving Takagi-Sugeno (T-S) fuzzy models for a nonlinear benchmark represented by the pendulum-crane system and focused on the dynamics of pendulum angular position behavior. The rule bases and parameters of T-S fuzzy models are continuously evolved by an online identification algorithm in terms of computing the potentials of new data points. Accepting the pendulum angle as model output, two T-S fuzzy models are derived, viz. with a single input and with three inputs. The experimental results are obtained for a pendulum-crane laboratory equipment system and they show the performance of the proposed evolving T-S fuzzy models. © 2012 IEEE.

Open Access: Yes

DOI: 10.1109/CogInfoCom.2012.6422044

Speed and position control of BLDC servo systems with low inertia

R. C. Pozna Mircea Bogdan Rǎdac Claudia Adina Dragos Alexandra Iulia Stînean Radu Emil Precup Stefan Preitl

Publication Name: 2011 2nd International Conference on Cognitive Infocommunications Coginfocom 2011

Publication Date: 2011-09-22

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

The paper deals with applicative aspects concerning the control of speed and position of a BLDC servo system with low but Variable in a given range Moment of Inertia (VMI). Detailed models of various applications, some control solutions are discussed and developed and part of them tested on the basis of the specific features of the plants with VMI. The adopted control solutions PI(D) control (as reference solution) and fuzzy control with homogenous and non-homogenous dynamics are briefly presented and some approaches regarding the methods are highlighted. Due to the applicability of the methods in the field of mechatronics applications with VMI (speed and positioning control of rapid plants), the presented aspects are of permanent actuality, and they offer directions of future research. © 2011 Scientific Assoc Infocomm.

Open Access: Yes

DOI: DOI not available

Modeling of a vehicle with continuously variable transmission

R. C. Pozna Claudia Adina Dragos C. S. Nes E. M. Petriu D. Pirlea Radu Emil Precup Stefan Preitl

Publication Name: 19th International Workshop on Robotics in Alpe Adria Danube Region Raad 2010 Proceedings

Publication Date: 2010-09-01

Volume: Unknown

Issue: Unknown

Page Range: 441-446

Description:

The paper presents aspects concerning the modeling and driving scenarios of a class of vehicular power train systems. The modeling includes an analysis of the system components which include the spark-ignition internal combustion engine, the torque converter, the metal V-belt type continuously variable transmission and the wheels. Four driving scenarios are illustrated by digital simulation results: acceleration, overtaking maneuver, ramp encounter and engine brake. © 2010 IEEE.

Open Access: Yes

DOI: 10.1109/RAAD.2010.5524546

Takagi-Sugeno fuzzy controller for a magnetic levitation system laboratory equipment

R. C. Pozna Claudia Adina Dragos Jozsef K. Tar Raul Gherasim Bulzan Radu Emil Precup Stefan Preitl

Publication Name: Iccc Conti 2010 IEEE International Joint Conferences on Computational Cybernetics and Technical Informatics Proceedings

Publication Date: 2010-08-06

Volume: Unknown

Issue: Unknown

Page Range: 55-60

Description:

This paper presents the design and the implementation of two control solutions applied to a magnetic levitation system laboratory equipment. The first solution deals with a state feedback control structure to stabilize the controlled plant which is the inner control loop for the cascade control system structure proposed as the second solution. The second solution is based on a TakagiSugeno fuzzy controller in the outer control loop to ensure the zero steady-state control errors. Simulation and real time experimental results are included to illustrate the performance of the control systems and to validate the two control solutions in regulation and tracking. © 2010 IEEE.

Open Access: Yes

DOI: 10.1109/ICCCYB.2010.5491219