I have a UTV with a good winch if that helps. I know I can just rope a round and pull it up a ramp but I'm sure someone has come up with something a little easier. I'm not looking to start getting something welded at this point but I'm good with building something with scrap 2x4's or something like that.
Honestly for just a few rounds a ramp is a pretty good option. If you're going to be doing a lot of big wood, then a log lift. Other option is noodle & split to a manageable size.
I use an ATV ramp to roll rounds up into my truck bed, so I think a ramp would work for occasional use for a splitter. From my experience, pushing a round as heavy as I am up to truck bed height isn’t too hard, and if I needed to, I think I could do maybe 25 or 50% more. A splitter should be a bit lower, and if you make one, you could give yourself more mechanical advantage by building longer. I think I’d want some way to tie off the ramp to the splitter, and the splitter attached to a hitch, though. Bad things can happen fast.
I built one powered with my atv winch. Works good. I can tell you building one out of wood just won’t cut it. There’s a lot of forces (which I don’t quite understand myself) going through any such system. I bent the original pole fairly quickly. Repaired it a few times and eventually replaced it entirely with a beefed up version. If you want it to last and not possibly drop a 400lb round on yourself welding and steel is the way to go. And make it ten times stronger than you think it needs to be
Can't you stand the splitter up? Then you will never have to lift those big ones again! It makes splitting so much easier.
There are some ideas in the link below that have been discussed previously. A lot depends on the size of the rounds you are trying to lift. I have one of the receiver hitch game hoists and something like that could be modified to lift medium size rounds onto a splitter. (1) Log splitter cable lift. | Firewood Hoarders Club
I must say, before I rigged up a winch, etc., I would just noodle the heck out of it. A few years before I retired, I built a log splitter from scratch, for an old man who never let money get in his way of what he wanted, and it was super heavy duty, and had a hydraulic lift that would raise a big round up to the horizontal splitter which was huge and would split rounds in 4 sections with every stroke. There's some on the market similar, and I tried to talk him into just buying one, but his personality would never allow that, so we built it for him and I seen in operation afterwards, and it was a monster. He has since passed on, and I don't know what ever happened to it.