Cultural support for improvisation

We present a novel object-centered formalization of action which allows us to define an interesting class of tasks, called cooking tasks, which can be performed without backtracking. Since backtracking is unnecessary, actions can be selected incrementally using a greedy method wihtout having to precompute a plan. Such an approach is efficient and rapidly adjusts to unforeseen circumstances. Our argument is that cooking tasks are widely encountered in everyday life because of the special properties of a given culture's artifacts. In other words, culture has structured the world so as to make it easier to live in. We present an implementation of these ideas, experimental results, and control experiments using a standard nonlinear planner.