We have built several handicap ramps.
I am like others having a problem visualizing how "cob" and "ramps" go together.
I also was not familiar with the term "Cobins"
Amy said, I'd like to eventually build multiple pallet cobins connected subsurface with earthen ramps.
I found this thread which helps explain "cobins":
https://permies.com/t/65885/Palletable-Cobins
I am assuming you want the "Cobins" to be underground? And the "Cob Ramps" will lead to the underground "Cobins"
Would it be possible to sketch something like what you have in mind and post to the forum?