  We predict that stable mobile spatio-temporal solitons can exist in arrays of
periodically curved optical waveguides. We find two-dimensional light bullets
in one-dimensional arrays with harmonic waveguide bending and three-dimensional
bullets in square lattices with helical waveguide bending using variational
formalism. Stability of the light bullet solutions is confirmed by the direct
numerical simulations which show that the light bullets can freely move across
the curved arrays. This mobility property is a distinguishing characteristic
compared to previously considered discrete light bullets which were trapped to
a specific lattice site. These results suggest new possibilities for flexible
spatio-temporal manipulation of optical pulses in photonic lattices.
