3. Self-assembly and Self-repair Method

3. Self-assembly and Self-repair Method

A self-assembly and self-repair method has been developed to allow the collection of units to transform itself into desired structure from an arbitrary initial configuration. The proposed method is implemented in such a way that each unit has identical software as well as its hardware, so that any unit can play any role in the system.
The method is also implemented in a distributed way by using local information, preserving the robustness and concurrency of the self-reconfiguration process. This is an important issue especially in a large-scale system, where the conventional centralized control of the whole system by a single coordinator becomes difficult because of load concentration and communication bottleneck.
A computer simulation of self-assembly of a 56-unit structure is shown below. Starting from a box shape, the target structure is formed in a distributed manner. The shaded units have already reached a position in the target shape.


< Initial state >		< Starting self-assembly >

		< Self-assembly of the target shape completed >

Animation of self-assembly (MPEG, approx. 23MB) Self-repair process is also shown below. The original target shape can be restored using spare units when some part is damaged.


< Some part damaged >		< Self-repair in progress >	< Self-repair completed >

The computer simulation demonstrated that self-assembly and self-repair of three-dimensional structure is feasible by homogeneous mechanical units in a distributed manner.