In this chapter we have introduced the concept of characteristic transfer functions and seen that these may not be ratios of polynomials in s. No difficulty, however, is encountered in evaluating these functions along s =jω to find the characteristic loci. It has further been shown how the characteristic loci can be used to determine the stability of a multivariable system and how one approach to the design of a controller is basically an exercise in shaping characteristic loci.

Inspec keywords: eigenvalues and eigenfunctions; polynomials

Other keywords: multivariable system; characteristic locus method; polynomials; transfer functions

Subjects: Algebra, set theory, and graph theory