Lecture AI Planning

Planning in AI
Principle of Least Commitment

Only make choices when forced.
--> Avoids unnecessary backtracking.

Represented graphically in Russel and Norvig.

A plan is a structure consisting of
-A set of plan steps. Each step is an operator.
-A set of step ordering constraints.

Slide 16
Hubble Space Telescope



OP: Assemble(X)
Pre: Painted(X)
Post: Assembled(X)

OP: Finish
Pre: Corrected(M), Polished(M), Assembled(H)
Post: _____

So you just work through this, identifying pre and post conditions.

In the 3rd assignment, this is relevant way of dealing with the planning problem in there. (Using the POP algorithm).

The STRIPS language is fairly limited, but it is restricted intentionally.
But this makes it too restricted for complex, realistic domains.
You can make it more complex with conditional effects.

But what about when the world becomes uncertain? How does it deal with that then?
The POP algorithm dies. It does not cope with that.