How to move a group of granules with constant velocity without rotation of these granules?

I am assigning a clump of granules to a group and I would like to move this group with constant velocity without rotation as it moves into another collection of granules. Fix move only affects the translational velocities but I noticed the rotational velocity changes when I want it to be 0. Is it possible to do this via fix rigid (just fix rigid not fix rigid/nve) and then turn off torque, and then use fix move?

I would also like to find the total force exerted on these granules so that I can compute the workdone by them as they push on other granules. Would that just be compute property/atom on the group of rigid molecules?

You must not time integrate atoms twice. LAMMPS spits out a big warning about this. In fact, I suspect, that the effect you are seeing is exactly because of having atoms that are time integrated multiple times. I cannot see how otherwise the rotational velocity of particles subject to fix move can be updated.

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