We realize a coherent transfer of mechanical excitation in a finely controlled artificial nanomechanical lattice.We also realize strong dynamic coupling between adjacent high-Q mechanical resonators,via modulated dielectric force at the frequency difference between them.An excitation transfer across a lattice consisting of 7 nanobeams is observed by applying a design sequence of switching for couplings,with the final effective population reaching 0.94.This work not only demonstrates the ability to fully control an artificial lattice but also provides an efficient platform for studying complicated dynamics in one-dimensional systems.