  We introduce a system where an elastic lattice of particles is moved slowly
at a constant velocity under the influence of a local external potential,
construct a rigid-body model through simplification processes, and show that
the two systems produce similar results. Then, we apply our model to a
superconducting vortex system and produce path patterns similar to the ones
reported in [Lee et al., Phys. Rev. B 84, 060515 (2011)] suggesting that the
reasoning of the simplification processes in this paper can be a possible
explanation of the experimentally observed phenomenon.
