David Guerrero, Vicente Hernandez and Jose E. Roma

SLICOT Working Note 2001-3: June 2001.

This report describes the integration of some routines for solving standard Lyapunov equations by Hammarling's method on parallel machines

Erik Elmroth, Pedher Johansson, Bo Kågström and Daniel Kressner

SLICOT Working Note 2001-2: January 2001, revised June 2001

A prototype web computing environment for computations related to the design and analysis of control systems using the SLICOT software library is presented. The web interface can be accessed from a standard world wide web browser with no need for additional software installations on the local machine. The environment provides user- friendly access to SLICOT routines where run-time options are specified by mouse clicks on appropriate buttons. Input data can be entered directly into the web interface by the user or uploaded from a local computer in a standard text format or in MATLAB binary format. Output data is presented in the web browser window and possible to download in a number of different formats, including MATLAB binary. The environment is ideal for testing the SLICOT software before performing a software installation or for performing a limited number of computations. It is also highly recommended for education as it is easy to use, and basically self-explanatory, with the users' guide integrated in the user interface.

Petko Petkov, Da Wei Gu and Mihail Konstantinov

SLICOT Working Note 2001-1: January 2001.

In this paper we apply some of the SLICOT routines in the mu-synthesis of a robust control system for a triple inverted pendulum. We consider the case of a mixed type uncertainty consisting of two complex uncertainties in the actuators, three real uncertainties in the moments of inertia and three real uncertainties in the viscous friction coefficients. Using the D-K iteration, a further fictitious complex uncertainty block is included and a mu-controller is constructed for which the closed-loop control system achieves robust stability and robust performance as requested. The influence of the individual uncertainty on the robust stability is investigated using mu-analysis. In addition a reduced order controller is found such that the robust stability and robust performance of the closed-loop system are preserved with the much lower order controller. In the design, the structured singular value mu is calculated with the SLICOT routine AB13MD and the model reduction toolbox in SLICOT is used in the model reduction of the mu controller. The computation experience shows that the SLICOT routines perform better than the counterpart routines in MATLAB in terms of speed and accuracy.

Da Wei Gu, Petko Petkov and Mihail Konstantinov

SLICOT Working Note 2000-6: December 2000.

This report briefly introduces the H_inf loop shaping design procedure (LSDP) in the discrete-time case as well as its implementation in the software package SLICOT. Solution formulae are presented with the exposure of a relationship between the solutions to the three discrete-time, algebraic Riccati equations (DARE) required in the construction of an LSDP controller. These SLICOT routines also produce estimates of the condition numbers of the DARE solutions, which reveals the accuracy and reliability of the computational results. The developed routines are tested in a design example, and are included as appendices.

Vicente Hernandez, Ignacio Blanquer, Enrique Arias, Victor Garcia, Lourdes Penalver and Pedro Ruiz

SLICOT Working Note 2000-5: August 2000.

This report presents the SLICOT implementation of the nonlinear control systems toolbox. A common interface to several ODE and DAE libraries is prepared. This interface is the entry point to the SLICOT solvers and enables users to test the advantages of different approaches. In addition, an implementation of a MATLAB gateway to the nonlinear control systems simulation interface is developed which enables the user to define the problems using matlab code, including the definition of the system functions and Jacobians. Also, the performance of the toolbox using benchmark problems, as well as industrial test cases is described.