Response Strategy to Environmental Cues for Modular Robots with Self-Assembly from Swarm to Articulated Robots

This paper proposes a strategy for a group of swarm robots to self-assemble into a single articulated(legged) structure in response to terrain difficulties during autonomous exploration. These articulated structures will have several articulated legs or backbones, so they are well suited to walk on difficult terrains like animals. There are three tasks in this strategy: exploration, self-assembly and locomotion. We propose a formation self-assembly method to improve self-assembly efficiency. At the beginning, a swarm of robots explore the environment using their sensors and decide whether to self-assemble and select a target configuration from a library to form some robotic structures to finish a task. Then, the swarm of robots will execute a self-assembling task to construct the corresponding configuration of an articulated robot. For the locomotion, with joint actuation from the connected robots, the articulated robot generates locomotive motions. Based on Sambot that are designed to unite swarm mobile and self-reconfigurable robots, we demonstrate the feasibility for a varying number of swarm robots to self-assemble into snake-like and multi-legged robotic structures. Then, the effectiveness and scalability of the strategy are discussed with two groups of experiments and it proves the formation self-assembly is more efficient in the end.