The two really standout things for me are, 1) they did this on an outdoor track/around campus, not in the lab and 2) they did the entire 5K on a single battery

The two really standout things for me are, 1) they did this on an outdoor track/around campus, not in the lab and 2) they did the entire 5K on a single battery charge. It looks like a guy was controlling the direction using an RC unit, so there's no optical guidance etc, but still, traversing Real World terrain (even if it's paved walkways), and doing it in an energy-efficient manner is pretty impressive.