  A fractal method to detect, locate and quantify chaos in
multi-dimensional-conservative-closed systems, based on the creation of
artificial exits, is presented. The method is invariant under space-time
changes of coordinates and can be used to analyse both classical and
relativistic Hamiltonian systems of more than two degrees of freedom. As an
application of the method we study a couple of two standard maps associated to
a periodically kicked rotor of $2{1/2}$ degrees of freedom.
