## 5 – 25 Situation Calculus 3 V2

So I’ve talked about the possibility axioms and the successor-state axioms that’s most of what’s in situation calculus. And that’s used to describe an entire domain like the airport cargo domain. And now we describe a particular problem within that domain by describing the initial state. And typically we call that S0, the initial situation. … Read more

## 4 – 24 Situation Calculus 2 V4

Now, there’s a convention in situation calculus that predicates like ‘at’, we said plane ‘p’ was at airport ‘x’ in situation ‘s’. These types of predicates that can vary from one situation to another are called fluents from the word fluent, having to do with fluidity or change over time. And the convention is that … Read more

## 3 – 23 Situation Calculus 1 V3 (1)

Now I want to talk about one more representation for planning, called Situation Calculus. [INAUDIBLE], suppose we wanted to have the goal of moving all the cargo from airport A to airport B, regardless of how many pieces of cargo there are. You can’t express the notion of all in propositional languages like classical planning, … Read more

## 2 – 22 Sliding Puzzle Example

To understand the idea of heuristics, let’s talk about another domain. Here we have this sliding puzzle domain. Remember, we can slide around these little tiles, and we try to reach a goal state. 16 puzzle is kind of big, so let’s show you the state space for the smaller 8 puzzle. And here’s just … Read more

## 1 – PlanSpaceSearch

Now there’s one more type of search for plans that we can do with the classical planning language that we couldn’t do before. And this is, searching through the space of plans rather than searching through the space of states. In forward search, we were searching through concrete world states. In backward search, we were … Read more