AgileQuad is a research quadrotor drone used to develop autonomous systems that can dodge trees or other bothersome objects. Even random fencing opponents.
(AgileQuad fencing avoidance drone)
MIT's Computer Science and Artificial Intelligence Lab (CSAIL) has made great strides at helping fixed-wing drones dodge trees, and Stanford's Autonomous Systems Laboratory, meanwhile, has been working on a project called AgileQuad for quadcopters. Does it work? Well, it only takes one video of a human vs. drone fencing match to show how adept the little flier is at dodging things that are actively trying to hit it:
Although I don't know of any object avoidance drones in science fiction, I can't help but think that this research would benefit the creation of a fencing robot like the one that Frank Herbert conceived of for Dune. Also, those fancy speeders on forest moons in Star Wars would be much more user-friendly if they could avoid hitting trees on their own.