DisCo: A Multiagent 3D Coordinate System for Lattice Based Modular Self-Reconfigurable Robots

Localizing each module in a modular self-reconfigurable robot (MSR) is of paramount importance. In MSR, the communication graph is directly mapped to the real topology which makes the localization problem easy to solve. However, some types of connectors can lose the orientation of the modules, making the problem intractable. In this work, we propose to build a coordinate system for 3D lattice-based modular robots using a multiagent system. We present DisCo algorithm, that uses one agent per module which can only communicate with its connected neighbors and that does not need a central coordination system. We show that the agents can tackle any kinds of 3D lattice and we illustrate it with a Face Centered Cubic lattice (12 neighbors) and a cubic lattice (6 neighbors). Using communications and only four states, DisCo can also deduce the orientation of modules if the connectors do not provide this information.