flex Expert System Toolkit - LPIS

11. Example – Robbie Goes Shopping 157
10. Example - Robbie Goes Shopping
We will now consider a flex example, using the KSL, adapted from the book
Artificial Intelligence by Patrick Henry Winston (published by Addison
Wesley), page 169.
The Problem
Robbie is a robot who bags groceries in the following way:
• ask the user to choose their initial shopping list.
• check that the list is 'complete' according to the requirements :
• if any snacks are on the list then there is also a drink.
• if butter is on the list then so is bread, and vice versa.
• pack the items on the shopping according to the requirements :
• pack any frozen items first.
• pack the large items, beginning with any large bottles.
• pack all the medium items.
• finally, pack any remaining small items.
We can consider the solution to this problem in two phases:
1 The configuration phase - in which the initial shopping list is
established.and then checked to see if everything necessary has been
included. The shopping list is then adjusted accordingly.
2 The resource allocation phase - in which the items on the final shopping
list are packed into bags in terms of their size and type.
The Configuration Section
The initial shopping list is established and then checked, to see if everything
necessary has been included. The shopping list is then adjusted accordingly.
flex toolkit
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