Even with a sure-stepping robot like DARPA's Big Dog, there is still plenty of terrain that today's robo-mules simply can't handle. That's why a team of researchers from ETH Zurich's Autonomous Systems Lab has devised a way to ensure these robots never get bogged down by impassible terrain: pair that robot with a forward-scouting UAV.
The mechanical pair are designed to cooperate with one another to map and navigate changing terrain. The UAV first flies ahead and creates a rough map of the area, including relative elevations. It then shares that data with the walking robot, which determines the most efficient route to take. The legged robot also employs a laser rangefinder to continually update its elevation map and ensure that every step it takes is sure-footed. The team's study, "Collaborative Navigation for Flying and Walking Robots" is currently under peer review ahead of the 2016 IEEE International Conference on Robotics and Automation.
This post has been updated. Previous mentions of "packbot" have been changed since "PackBot" is technically an iRobot trademark.