I saw Rowan talk about this while he was doing a research talk. F1TENTH also talks about this.
Actually, this is a pretty simple idea. A holonomic robot is a robot capable of moving in any direction by drawing a straight line.
It doesn’t have to reposition itself.
Ackermann Steering is non-holonomic. Any sort of car is non-holonomic.
Reference for equations: https://roboticsknowledgebase.com/wiki/planning/planning-overview/#sampling—vs-search-based-methods