What remains an obstacle in developing battery-run four-legged robots?

Scientists have been experimenting with four legged robots for years, trying to see if they could be used as pack animals for carrying heavy loads over a difficult terrain. But the machines power requirements limited their potential. That’s changed now with a running robot designed by a group of engineers that operates on batteries, rather than on heavy gasoline powered engines. Scientists say these new robots will soon be able to run like cheetahs. But for now, the different technologies that will bring them closer to everyday life are still being tested. One of the obstacles continues to be power consumption.