ABSTRACT
The form of mathematical model of the system under consideration determines restrictions and interconnections between sensitivity functions. These restrictions and connections may have the form of equalities of inequalities and be holonomic and non-holonomic. Differential sensitivity equations are natural non-holonomic restrictions imposed on sensitivity functions. Moreover, there are holonomic restrictions imposed on sensitivity functions of some types. Many characteristics of electronic networks are described with respect to parameters of homogeneous functions. The chapter considers systems described by ordinary differential equations or finite algebraic relations. It also considers mainly invariants with respect to semi-logarithmic sensitivity functions. The presence of sensitivity invariants adds some specifics to many investigation problems for dynamic systems, including automatic control systems. Thus, sensitivity invariants can restrict independent variation of sensitivity functions in the design of optimal insensitive systems. Three-dimensional stabilizer is included in most modern gyroscopic stabilization and inertial navigation systems.
