Emergent Restructuring of Resources in Ant Colonies : A Distributed Approach to Real World Engineering Problems

In this article two engineering problems are solved using colonies of artificial ant–like agents. These agents must restructure the resources in their environment in a manner which corresponds to a good solution of the underlying problem. The application areas considered are employed in parallel simulations of solutions of partial differential equations using the Finite Element Method. The problem domain is first discretised into a set of geometrical elements and solution for quantities such as material strain or pressure is computed at the element nodes. For parallel execution, the mesh is partitioned into submeshes so that the work can be scheduled equally amongst processors with the communication kept to a minimum. Communication occurs when two connected nodes are assigned to different processors. Standard approaches to these problems use recursive methods in which the final solution is dependent on solutions found at higher levels. For example partitioning into k sets is done using recursive bisection and meshing is often performed by creating an initial coarse-grained mesh and inserting extra nodes into the existing elements to achieve the required density. The inherently parallel, distributed nature of the swarm-based paradigm allows us to simultaneously partition into k sets or create different parts of the mesh at the same time. Furthermore, because this approach is dependent only on the state of the local environment it is ideal for problems of an adaptive nature which are difficult for standard approaches to tackle. Results show that this approach can be superior in quality when compared to standard methods. However, it is not as efficient and hence we outline various measures to both speed up and improve the quality of the methods presented. Keywords—Swarm algorithms, mesh generation, partitioning, computational science.