Hierarchical Planning for Self-reconfiguring Robots Using Module Kinematics

Reconfiguration allows a self-reconfiguring modular robot to adapt to its environment. The reconfiguration planning problem is one of the key algorithmic challenges in realizing self-reconfiguration. Many existing successful approaches rely on grouping modules together to act as meta-modules. However, we are interested in reconfiguration planning that does not impose fixed meta-module relationships but instead forms cooperative relationships between modules dynamically. This approach avoids the need to hand-code meta-module motions and potentially allows reconfiguration with fewer modules. In this paper we present a general twolevel reconfiguration framework. The top level plans in module-connector space using distributed dynamic programming. The lower level accepts a transition function for the kinematic model of the chosen module type as input. As an example, we implement such a transition function for the 3R, SuperBot-style module. Although not explored in this paper, this general approach is naturally extended to consider power use, clock time, or other quantities of interest.