IndiGolog: Execution of guarded action theories

IndiGolog: Execution of Guarded Action Theories Sebastian Sardiña Master of Science Graduate Department of Computer Science University of Toronto 2000 In AI, the problem of selecting (high-level) actions in dynamic and not completely predictable environments translates into the problem of designing controllers that can map sequence of observations into actions so that certain goals are achieved. One approach to high-level controllers is high-level programming. Basically, we imagine a system executing a high-level program with respect to a background theory of action. Whereas the background theory describes the characteristics of the domain (action preconditions, action effects and non-effects, etc.), the high-level program provides strong, but usually incomplete, clues about what the desired sequence of actions should be like. The work presented here combines two recent, but unexplored ideas: Guarded Action Theories and Incremental Program Execution. The result is a new high-level programming language, which we call IndiGolog, whose programs, compared with previous languages, are executed in a more practical way with respect to more open-world theories. We provide a theoretical exploration of both guarded theories and program execution, and develop a Prolog implementation for IndiGolog.