Question 10: AUTOMATED PLANNING\ The domain description of a blocks-w…

1    onTable(X)  -  X is on the table.
2    on(X,Y)     -  X is directly placed on Y.
3    clear(X)    -  X has nothing above it, it is clear.
4    holding(X)  -  The arm is holding X.
5    armEmpty    -  The arm is not holding any block, it is empty.

1    Pickup(X) - Pick up X directly from the table.
2       Preconditions: { armEmpty, clear(X), onTable(X) }
3       Add-Effects  : { holding(X) }
4       Del-Effects  : { armEmpty, onTable(X) }
5
6    Putdown(X) - Place X directly on the table.
7        Preconditions: { holding(X) }
8        Add-Effects  : { armEmpty, onTable(X) }
9        Del-Effects  : { holding(X) }
10   Unstack(X,Y) - Pick up X that is directly on Y.
11      Preconditions: { armEmpty, clear(X), on(X,Y) }
12      Add-Effects  : { clear(Y), holding(X) }
13      Del-Effects  : { armempty, on(X,Y) }
14
15   Stack(X,Y) - Place X directly on Y.
16      Preconditions: { holding(X), clear(Y) }
17      Add-Effects  : { armEmpty, on(X,Y) }
18      Del-Effects  : { holding(X), clear(Y) }