creation solid of solid body

Dear Lammps-users
I want to make a solid cylinder in a granular bed. I tried to make it with particles.But i want to make a solid cylinder which i want to use as an immersed body in granular flow . Is it possible to make a solid body in LAMMPS?

You can create collections of particles with create_atoms and the lattice
command and use of regions.

You can keep it “solid” during dynamics by using the fix rigid command.