Zebro's were developed in Delft from 2013 onwards. In Delft, based on work by Gabriel Lopez, the Zebro was inspired by RHex. RHex is a rough terrain robot developed by Boston Dynamics, and further elaborated upon by the Penn State University. At Delft, we do not claim to have invented six-legged walking!
We do however, give it our own spin by using the six legged robots as a platform for our swarm robotics testing. For more information and scientific proof of the benefits of six legged walking, your are kindly referred to the Penn State University website on RHex, as well as Boston Dynamics site.