A device for non intrusive agitation of a fluid, comprising: a container
adapted to contain the fluid, at least one of the walls thereof comprises a
membrane and a main movable stirring means located inside the
container adapted to stir at least the fluid. The first flexible element is
adapted to interfere mechanically with an external movable impulsion means
thus creating a deformation which has a mechanical interference with the main
movable stirring means. This movement of such impulsion means is
transmitted to the main movable stirring means by the interposition of the
first flexible element .