PDDL

Question

我是 pddl 规划的新手，现在我正在尝试创建域和问题文件作为练习。简短的领域描述：我有几辆汽车，可以在 A 和 B 的地方取放。任务很简单：把所有的汽车从 A 的地方拿走，然后把它们移到 B 的地方。我创建了以下域文件：

(define (domain test) ; Domain name must match problem's

  ; Define what the planner must support to execute this domain
  ; Only domain requirements are currently supported
  ( :requirements
    :strips                 
    :negative-preconditions 
    :equality               
    :typing               
    :adl
  )
 
 
  (:types
   car
   place
  )
  
  
  (:predicates
    (at ?o - car ?p - place )
    (taken ?o - car )
  )
  
   (:action take
   :parameters (?o1 - car  ?o2 - place )
   :precondition (and 
                    (at ?o1 ?o2)
                    (not (taken ?o1))
                 )   
   :effect (and 
             (not (at  ?o1 ?o2 ))
             (taken ?o1)
           )
   )
   
   
   (:action put
   :parameters (?o1 - car  ?o2 - place )
   :precondition (and 
                    (not (at ?o1 ?o2))
                    (taken ?o1)
                 )   
   :effect (and 
             (at  ?o1 ?o2) 
             (not (taken ?o1) )
           )
   )
   
   (:action takeAll
   :parameters ()
   :precondition (forall (?c - car ?p - place)
                    (and 
                    (at ?c ?p)
                    (not (taken ?c))
                    )
            )
   :effect (forall (?c - car)
                    (taken ?c)
                    )
            )
            
   )

问题文件如下所示：

(define (problem test)
    (:domain test)
    
    (:objects
    c1 - car
    c2 - car
    c3 - car
    
    A - place
    B - place
    )
    
    (:init
        (at c1 A)
        (at c2 A)
        (at c3 A)
        (not (taken c1))
        (not (taken c2))
        (not (taken c3))
    )

    (:goal (and
            (at c1 B)
            (at c2 B)
            (at c3 B)
            )
    )
    
  )

我正在使用可用的在线规划器和求解器here 我想知道为什么它输出我有几个无效谓词

test
  takeall precondition contains ["forall", ["?c", "-", "car", "?p", "-", "place"], ["and", ["at", "?c", "?p"], ["not", ["taken", "?c"]]]], not a valid predicate
  takeall effect contains ["forall", ["?c", "-", "car"], ["taken", "?c"]], not a valid predicate
  :equality requirement is unnecessary
test
  Initial state contains ["not", ["taken", "c1"]], not a valid predicate
  Initial state contains ["not", ["taken", "c2"]], not a valid predicate
  Initial state contains ["not", ["taken", "c3"]], not a valid predicate

有人可以向我解释一下我做错了什么吗？对于 takeAll 操作，我想用 forall 进行一些试验。并且应该这样解释：前提条件是说car类型的所有对象都不是处于一个状态，而是在某个地方。效果应该是所有的车都处于taken的状态。最短的解决方案应该是（按我的常识）takeAll, put(c1, B), (put c2, B), (put c3, B) 感谢您的帮助！

Answer 1

您正在进行经典规划，这意味着初始状态只需要指定什么是真的（其他一切都假定为假）。从你的 init 中删除那些负面的流利，它可能会成功。

PDDL - 无效谓词和 forall 的正确用法

PDDL - invalid predicates and correct usage of forall

planning

artificial-intelligence