NelinSys

A program tool for analysis and synthesis of nonlinear control systems based on MATLAB/Simulink 5.2

Created by Martin Ondera (during his studies at KKUI FEI TU Kosice and KAR FEI STU Bratislava)

The tool is available for free under the terms of General Public License (GPL).

The NelinSys library for MATLAB/Simulink 5.2 was initially created as a part of author's master thesis at the Department of Cybernetics and Artificial Intelligence, Faculty of Electrical Engineering and Informatics, Technical University of Kosice. Its main objective was to provide better program support for design and simulation of nonlinear control systems in MATLAB/Simulink environment. Afterwards, when the author began his studies at the Department of Automation and Control, Faculty of Electrical Engineering and Informatics, Slovak University of Technology in Bratislava, the library has been translated into English and supplemented with a few new functions. A few bugs have been fixed, too. The library is still being developed and a new version is planned to be released soon (perhaps in 2006).

The library consists of two relatively independent parts - Nonlinear Systems Analysis and Nonlinear Systems Synthesis. Besides function blocks designed for Simulink it also contains some applications designed directly for MATLAB and ready-made demo-simulations composed of the function blocks. This document serves as a help-base for the NelinSys library, it contains its detailed description as well as usage examples. System requirements necessary to work with the NelinSys library are mentioned at the end of this page.

NelinSys - a program tool for analysis and synthesis of nonlinear control systems

Nonlinear Systems Analysis

This part of the NelinSys library gives support to two different methods from nonlinear systems theory, namely the Phase Plane Analysis Method and the Two-Characteristics Method (also called the Describing Function Method). The first one is supported by four Simulink function blocks - Phase portraits... and the block Vector XY Graph for Phase Portraits, whereas the second is a Simulink-independent program application for MATLAB (for a more detailed description of either, click the corresponding icon in the following picture).

Nonlinear Systems Analysis

Nonlinear Systems Synthesis

This part of the library supports two popular methods of nonlinear control, the Exact Linearization and Gain Scheduling. Besides blocks directly connected with the methods, there are also others that serves as general-purpose Simulink blocks for nonlinear SISO and MIMO systems. For a more detailed description of individual blocks, click the corresponding icon in the following picture.

Nonlinear Systems Synthesis

Exact Linearization

Exact linearization

Gain Scheduling

Gain scheduling

System Requirements

As the NelinSys library was created for use with MATLAB/Simulink 5.2, its system requirements are almost the same as those of MATLAB. However, considering the large amount of symbolic operation, it is recommended for the computing power of the system to be slightly higher - it will shorten the time necessary for simulations to run. From the additional toolboxes of MATLAB, Symbolic Math Toolbox is required i.e. it must be properly installed before you start working with the library (Control System Toolbox is recommended, too).

As for the MATLAB version, the library is optimized for MATLAB 5.2 / Simulink 2.2 and was NOT TESTED with a different version. Nevertheless, it is possible that most functions will work fine also in combination with a higher version of the MATLAB software, or that only slight modifications of the program code are necessary in order to use it with e.g. MATLAB 5.3 or MATLAB 6. It is not recommended to use the library with a version of MATLAB or Simulink that is lower than 5.2 and 2.2, respectively.


Last modified: 9.10.2005