Mind Maps
The BJJ community is big on mind maps, which are close but not an exact match in your search for ontologies. For instance, Aesopian has this one:

This is not surprising, since the entire concept that set BJJ apart from judo was the idea of an inexorable flowchart:
- Takedown
- Pass guard
- Mount (using a broad definition of the term--not necessarily top mount, but also encompassing back mount, knee-on-belly, side control and so on)
- Choke, armbar, or strike without danger of counterstrikes
or
- Pull guard because we can't stop our opponent from taking us down
- Sweep to top
- Pass guard
- Mount
- Choke, armbar, or strike without danger of counterstrikes
The original vision now has many new spin-offs, but the underlying philosophy of having a gameplan has had a tremendous impact on jiu-jitsu mentality, as well as mixed martial arts strategies. Very few dispute the truth of the positional hierarchy, which when boiled down simply says it's better to be on top than on bottom.
Rickson was arguably the best in known history at implementing this plan. Here are his flowcharts:

Mapping my BJJ journey has more (including Rickson's), but most are not very "complete", preferring instead to just explain the contents of a particular DVD. For example:

Other arts
In my opinion, striking arts do not lend themselves particularly to mind maps or ontologies. There are way too many options--essentially it would just be a catalogue of techniques repeated several times over. The style of judo I'm familiar with doesn't use that kind of approach either, though I've heard that Russian and other Eastern bloc judo and wrestling coaches emphasize "chained" strategies that are similar. For instance, they'll attack with a particular technique, knowing that the opponent can only reasonably counter with A, B, or C, and for each of those they will have a fully fleshed out response, all the way down the chain to victory.