Research On Self-configuration Of Space Cellular Robots

As a self-reconfigurable modular robot,space cellular robots are able to deliberately change their own shape.By reorganizing cells or tissue to adapt to new environments,perform new tasks,or recover from damages.Each cell is an independent unit that is able to connect it to or disconnect it from other units to form various configurations dynamically.In this paper,the reconfiguration process of space cell robot is studied,the main contents include the description of robots' structure,reconfiguration control,and autonomous docking during self-reconstruction.Since the basic elements of space cell robots are different,the traditional methods can't describe its configurations completely.This paper presents a new kind of topology description-space connection matrix(SCM),whose elements are redefined.Combined the connection states of two cells(tissues)and the types of cells(tissues),it can describe the configuration of space cellular robots completely.By the SCM matrix,the isomorphism can be distinguished and branches in a configuration can be found,which is important for robot reconfiguration.According to the feature of cell structure and motion,this paper divides the self-reconfiguration process of space cell robot into self-deconstruction and self-assembly.By determining the common part of the initial configuration and the target configuration,the initial configuration is deconstructed into the common part.And then the common part is assembled into the target configuration.In the self-deconstruction process,this paper proposes to use the DFS depth-first search algorithm to transform the constructed SCM matrix into a standard expression connection matrix to determine whether the initial configuration and the target configuration are isomorphism.And then using the text comparison method to compare the sub-chains of the two configurations,eventually the common topology part is obtained.For autonomous connection during the self-configuration process,an improved energy climbing algorithm is used in this paper.According to the strength of the infrared sensor on the interface,the error of the two connection planes is corrected step by step to achieve the connection.This algorithm use the intensity of the infrared signal instead of the infrared numerical signal to determine the relative position,to avoid the coupling effect of the angle on the intensity of the infrared signal.At the end of this paper,the self-reconfiguration and the autonomous connection are simulated,and the effectiveness of self-reconfiguration strategy and autonomous connection strategy with infrared sensors are verified.