Observations on the behavior of discretely modulated spatiotemporal periodic structures

Spatiotemporal periodic structures are systems whose properties are periodically modulated both in space and time, able to support waves only in one direction, so breaking the so called reciprocity principle. Studies till now focused mainly on continuous systems, where properties are modulated in a continuous manner both in space and time. However, this is not the case of real mechanical systems: if on the one hand it is possible to think of a continuous temporal modulation by the means of an actively controlled smart material, on the other hand it is really hard to imagine a system that can be controlled punctually in space. For this reason discretely modulated structures are studied in this work, putting in evidence the differences with the continuous ones and providing some basis for the actual design of such a system.