许多现实世界中的规划问题通常希望规划目标能在尽可能短的时间内实现,并且规划动作的执行需要考虑时间因素。在规划图框架下,提出了一种能进行时态约束推理的遗传规划算法。主要工作有以下3个方面:1)介绍基于完全动作图的时序约束推理技术;2)提出能进行时序约束推理的基于规划图的遗传规划技术;3)针对基于规划图的遗传规划技术存在局部搜索能力不足的缺点,提出了在原有遗传操作算子的基础上,引入局部修复算子的混合规划技术。实验表明,这种算法能有效地处理一类时态规划问题。
Automated planning is the reasoning side of acting and temporal planning is a broad research area in intelligent planning. In most real-world applications, many real planning problems often require the planning goals can be satisfied in shorter time, and the execution of planning solution must take the time into account. In this paper, a temporal genetic planning algorithm is presented, which is under the framework of temporal planning graph and capable of reasoning about the temporal constraint. The main contributions of this algorithm consist of: (1) Presenting a temporal planning graph under the planning graph by making time explicit in the representation, and giving a new temporal constraint reasoning technology to handle the temporal problems based on the full temporal action subgraph, (2) Encoding the candidate planning solutions into chromosomes and making an adaptive evaluation function, using genetic algorithm to deal with temporal planning problems under the framework of the temporal planning graph, and (3) Stating the meaning of the local fix operator, presenting a hybrid approach which combines this operator with the traditional genetic operators to strengthen the algorithms' capability of local search, so that the algorithms can converge faster and find a planning solution finally. The experiments show that the algorithm can deal with efficiently a kind of simple temporal planning problem.