So our team was thinking of putting mecanum wheels with a dr4b and the question we had was is it possible to make a dr4b on top of Mecanum wheels and still make the space requirement for the robotand are there any other teams that have done so?
I suggest you and your team draw it out. Remember that C-channels are not exactly 1/2". The long side is .5625"
I’m not sure I completely understand the question, but using mecanum wheels on your chassis should have very little to do with your lift.
The 4” mecanums to not take up more vertical space than 4” wheels of any other type.
The main issue you might run into is that you might need to make your lift base tower shorter, which shouldn’t pose too much of a problem.
You can make a strong lift tower with simply a c-channel and a triangular support piece, which mounts virtually everywhere. If you can’t find a place for a tower inside the drive base, consider moving the front wheels back an inch to make room.
Side note it’s best to try to build the robot holistically, meaning you shouldn’t just make a drive train and a lift and then attach them. You should design the drive train and lift to fit together ahead of time.