The Illinois Institute of Technology's Robotics Lab is working on an interesting variation of the popular quadrotor flying robot. They've added a rolling cage that allows the robot to roll along the ground as well as fly. Why would you want to do that? Because rolling requires a lot less power than flying. From the researchers:
Experimental results show that the hybrid robot can travel a distance 4 times greater and operate almost 6 times longer than an aerial only system. It also solves one of the most challenging problems in terrestrial robot design — obstacle avoidance. When an obstacle is encountered, the system simply flies over it.
The research on this project is being done by Arash Kalantari and Matthew Spenko of IIT. The lab is also working other interesting projects including perched landing of micro air-vehicles, agile non-holonomic robots, and omnidirectional rough terrain robots. See the Robotics Lab research projects page to read more about out their other robots. Read on to see video of the HyTAQ robot rolling and flying.