Everybody who has done research in robotics knows that teaching robots to navigate uneven terrain is easier said than done. Researchers are making progress in this area all the time though. This video shows the Atlas Humanoid walking over partial footholds like small stones while keeping its balance.
After each step, the robot balances itself on the new foothold by shifting its weight around properly. Here is what the researchers had to say about the experiment:
To maintain balance we combine fast, dynamics stepping with the use of angular momentum (lunging of the upper body). The control algorithm was developed at IHMC, the robot was build by Boston Dynamics.