Multi-layered PSMs for planning

Abstract

PSM are essential components in any modern knowledge methodology because they provide us with some guidelines that facilitate the building of knowledge-based system and promote the reusability of development efforts. However, it is recognised that the reusabilty of any PSM will decrease as the complexity of the task to be modelled increase. If we consider that actual tasks are complex enough, we may conclude that the effective reusability of a PSM is very limited. In order to minimise this inconvenience, we propose to use two layers of PSM. One layer will model the primitive tasks the system is composed of. The other layer will control the execution order of these tasks in order to reach to a global solution. This paper describes how we have applied this schema over a planning task on the Search and Rescue domain.