  The paper considers some class of dynamical systems that called density
systems. For such systems the derivative of quadratic function depends on
so-called density function. The density function is used to set the properties
of phase space, therefore, it influences the behaviour of investigated systems.
A particular class of such systems is previously considered for (in)stability
study of dynamical systems using the flow and divergence of a phase vector. In
this paper, a more general class of such systems is considered, and it is shown
that the density function can be used not only to study (in)stability, but also
to set the properties of space in order to change the behaviour of dynamical
systems. The development of control laws based on use the density function for
systems with known and unknown parameters is considered. All obtained results
are accompanied by the simulations illustrating the theoretical conclusions.
