Hierarchical robots

This paper introduces the concept of hierarchical robots, which is a type of modular robots assembled from a hierarchy of modules, and a preliminary realization of this concept: the Odin robot. Odin currently consists of ten modules of two different classes, one class of modules provide structure and the other actuation. We describe the mechanical design of these modules and their electrical design with specific focus on their hybrid communication system whose topology can be changed on-line. We demonstrate the features of this communication system in a simple experiment and also demonstrate how the assembled Odin robot can produce locomotion. While it is too early to make a conclusion regarding the usefulness of hierarchical robots in general, we think that our work indicates that we may be able to simplify the manufactured modules at the bottom of the hierarchy while increasing the functionality of the assembled hierarchical robot.