  In this paper we propose a new way of obtaining four dimensional gauge
invariant $U(n)$ gauge field from a bulk action. The results are valid for both
Randall-Sundrum scenarios and are obtained without the introduction of other
fields or new degrees of freedom. The model is based only in non-minimal
couplings with the gravity field. We show that two non-minimal couplings are
necessary, one with the field strength and the other with a mass term. Despite
the loosing of five dimensional gauge invariance by the mass term a massless
gauge field is obtained over the brane. To obtain this, we need of a fine
tuning of the two parameters introduced through the couplings. The fine tuning
is obtained by imposing the boundary conditions and to guarantee non-abelian
gauge invariance in four dimensions. With this we are left with no free
parameters and the model is completely determined. The model also provides
analytical solutions to the linearized equations for the zero mode and for a
general warp factor.
