# Computer Algebra Algorithms for Nonlinear Control

## Abstract

This paper describes some of the computer algebra algorithms for nonlinear control systems design embodied in CONDENS, a symbolic manipulation software system, which employs certain differential geometric tools for the analysis and design of control systems. Feedback equivalence among nonlinear systems is used to linearize and thereby control certain classes of nonlinear control systems. Left and right invertibility of nonlinear systems is used to solve the output tracking problem. CONDENS makes these analytical procedures available to users who may not have an extensive knowledge of differential geometry. The system consists of a main part containing functions that perform basic differential geometric computations, two modules for study and analysis of nonlinear control systems, and two packages for the design of nonlinear controllers for the output tracking problem. We shall discuss the implementation of these packages and the functions they include.

## Keywords

Nonlinear System Computer Algebra System Nonlinear Control System Fortran Code Controllable Linear System## Preview

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