This paper deals with an unidimensional analytical modelling of the vibratory behaviour of a rectangular beam excited by several piezoelectric ceramics glued on its lower face. The establishment of the equations of motion is guaranteed by the application of Hamilton’s principle. From this approach, it results an accurate knowledge on the mode shape in function of the geometry, the structure and the positions of the piezoelectric actuators. These cleverly chosen degrees of freedom consequently enable to promote peculiar mechanical vibratory mode, advantage experimentally validated. This approach deployed on a simple case falls within a general process of the surface tactile devices optimization. The planned applications use the reduction of the effective friction by the generation of an air film between the vibrating plate and the user’s finger by means of piezoelectric ceramics.