Artificial Intelligence

The original STRIPS planner was designed to control Shakey the robot. Figure 10.14 shows a version of Shakeys world consisting of four rooms lined up along a corridor, where each room has a door and a light switch. The actions in Shakeys world include moving from place to place, pushing movable objects (such as boxes), climbing onto and down from rigid objects (such asboxes), andturning light switches onandoff. Therobot itselfcould notclimb on a box or toggle a switch, but the planner was capable of nding and printing out plans that were beyond the robots abilities. Shakeys six actions are the following:

Go(x,y,r), which requires that Shakey be At x and that x and y are locations In the same room r. By convention a door between two rooms is in both of them.

Push a box b from location x to location y within the same room: Push(b,x,y,r). You will need the predicate Box and constants for the boxes.

Climb onto a box from position x: ClimbUp(x,b); climb down from a box to position x: ClimbDown(b,x). We will need the predicate On and the constant Floor.

Turn a light switch on or off: TurnOn(s,b); TurnO (s,b). To turn a light on or off, Shakey must be on top of a box at the light switchs location.

Write PDDL sentences for Shakeys six actions and the initial state from Figure 10.14. Construct a plan for Shakey to get Box2 into Room2.

Switch Thw4 Room 4 Room 3 Shake Corridor IN Room 2 Nach Room 1 Figure 10.14 Shakey's world. Shakoy can move between landmarks within a room, can paws through the door between rooms, can clickimtable objects and pushushable atjects, and can lip light switches