This is my first post...so be gentle ;-) Not sure I'm posting the right way or in the right place.
Like many of us, we have rocks in our fields...many rocks. While the idea of buying a used rock picker doesn't seem terrible, there are other items higher on our "needs" list. I'd like to help develop a ground driven, rock picker...mobile enough to move from farm to farm, but not too heavy to make unwieldy. It would need to track directly behind the tractor when being moved (so that being said, it'll be an implement not it's own unit), but then can fold out so it's outside of a tractor's travel path.
A unit that has a 3 scraping/filtering bucket (like a Degelman) seems to be a good design.