how to perform box deformation every specified timesteps with velocity defrom

dear lammps members:
I’m dealing with a tensile problem(a beam, the unit is METAL). When i trying to output the strain, i found the box didn’t deformation each time step. Instead, it change roughly 1000 steps(1 picoS) . I want to know is there any commands could be used to control the box deform frequency with s s s boundary and velocity command ? Like the “N” in " fix deform" command

Thanks in advance.

boxsize.txt (754 Bytes)

If you don't have a periodic system, deforming the box does not make much sense. A more appropriate model would be to apply strain by using fix move or displace_atoms.