Round bale unroller plans

I need to build a bale unroller this week and I'm looking to see if anyone has plans laying around.  I have drawn up a couple and I'll eventually CAD it out in Solidworks, but I would like to see what someone else has done as well.  I am mainly looking for the square tubing size used and recommendations on that.   Based on Greg Judy's design and a few others I will copy/modify the basics but I always appreciate other ideas.  

I can often look at an existing unit and just copy it.
Have you thought of that? Does it need to be driven?
I think I have seen one where you cut the wrapping, roll out some it sits on the ground and as you move forward the friction between the ground
and the partial roll draws the hay off the spool.

I had to look up what a round bale unroller was to see what it was.

Here are some pictures and youtube so others will know too:

Soil Fertility and Good Feed – That’s Why Greg Judy Unrolls Hay

Back in 1999 when we first started leasing idle land for grazing that needed serious fertility, I designed my first bale unroller. We had all these old farms that had been stripped

source







source

Thank you for sharing this concept.