与 PDDL 错误作斗争，没有任何计划可以解决它

Question

我试图让我的 PDDL 计划运行，经过几次迭代后，我的代码运行时没有任何语法错误，但是在尝试计划时，我收到以下错误。 “ff：目标可以简化为 FALSE。没有计划可以解决它”

我确定我的逻辑有问题，但我一辈子都找不到问题所在。基本前提是送货无人机采摘

领域：

(define (domain delivery-drone)
    (:predicates
        (needs-package ?house)
        (package-received ?house)
        (is-house ?house)
        (is-drone ?drone)
        (at-station ?drone)
        (carrying-package ?drone)
        (at-house ?drone)
        (is-package ?package)
        (being-carried ?package)
        (tobe-delivered ?package)
        (package-delivered ?package)
        (is-station ?station)
        (is-empty ?drone))
        
    (:action pickup-package
        :parameters (?drone ?package)
        :precondition (and (is-drone ?drone)
                           (is-package ?package)
                           (at-station ?drone)
                           (tobe-delivered ?package)
                           (is-empty ?drone))
        :effect (and (carrying-package ?drone)
                     (being-carried ?package)
                     (not (is-empty ?drone))))
    
    (:action deliver-package
        :parameters (?drone ?house ?package ?station)
        :precondition (and  (is-drone ?drone)
                            (is-station ?station)
                            (is-house ?house)
                            (at-station ?drone)
                            (carrying-package ?drone)
                            (needs-package ?house))
        :effect (and (is-empty ?drone)
                     (package-delivered ?package)
                     (package-received ?house)
                     (at-house ?drone)
                     (not (carrying-package ?drone))
                     (not (needs-package ?house))
                     (not (tobe-delivered ?package))
                     (not (being-carried ?package))
                     (not (at-station ?drone))))
                          
    (:action fly-station
        :parameters (?drone ?house ?station)
        :precondition (and  (is-drone ?drone)
                            (is-house ?house)
                            (is-station ?station)
                            (at-house ?drone)
                            (is-empty ?drone)
                            )
        :effect (and (at-station ?drone)
                     (not (at-house ?drone)))))

问题：

(define (problem delivery-drone-6houses)
    (:domain delivery-drone)
    (:objects drone station house-a house-b house-c house-d house-e house-f package-a package-b package-e package-f)
    (:init (is-drone drone)
           (is-station station)
           (is-house house-a)
           (is-house house-b)
           (is-house house-c)
           (is-house house-d)
           (is-house house-e)
           (is-house house-f)
           (is-package package-a)
           (is-package package-b)
           (is-package package-e)
           (is-package package-f)
           (needs-package house-a)
           (needs-package house-b)
           (needs-package house-e)
           (needs-package house-f)
           (is-empty drone)
           (tobe-delivered package-a)
           (tobe-delivered package-b)
           (tobe-delivered package-e)
           (tobe-delivered package-f))
    (:goal (and
           (package-received house-a)
           (package-received house-b)
           (package-received house-e)
           (package-received house-f))))

任何提示或建议将不胜感激。

Answer 1

无人机不在车站，除非在房子里，否则无法到达那里。尝试在您的(:init) 中添加：(at-station drone)。