Propositional STRIPS Planning Task Sample Clauses

Propositional STRIPS Planning Task. The tuple ⟨A , O, I , G ⟩ defines the STRIPS planning task P, where: • A is a finite set of ground atomic formulas, called the condition; • O is a finite set of operators, where each operator consists of: – Pre-conditions, which are satisfiable conjunctions of conditions, either posi- tive (o+) or negative (o−); – Post-conditions, which are satisfiable conjunctions of effects (changes to the conditions once the operator is applied), either positive (o+) or negative (o−), also known as the add and delete lists. • I is the initial state; • G represents a set of goals, which is defined as a satisfiable conjunction of positive and negative conditions. A solution to a STRIPS planning task is called a plan, which would be a sequence of ordered actions that would allow the agent to reach its goal state, starting from an initial state. Definition 2 (Plan) A sequence of actions π = ⟨a1, a2, . . . , an⟩ is said to be a plan for a STRIPS planning task, if and only if applying the actions from π on the initial state I , will reach a state where G is true. Following the success of STRIPS, research in the area of action planning grew and resulted in several other formal descriptions being created. ADL (Action Description Language) [112] was based on the state-transition model of actions, and it combined the computational benefits brought by STRIPS and the power of calculus.