基于事例推理的自由曲面型汽车前照灯方案设计方法

摘要

快速地确定满足配光要求的自由曲面型前照灯的设计方案，是车身造型的要求。采用基于事例推理的方法，首先研究了面向对象的前照灯事例表达模型，然后根据最近邻事例检索方法，利用车灯包围盒和布置坐标系等预处理工具，建立了前照灯事例索引模型和匹配算法，提出了约束满足和尺寸驱动求解相结合的前照灯事例修改算法。应用实例表明，所提出的方法能在前照灯方案设计中引入工程设计要求，快速产生符合要求的设计方案，能够有效地克服工程要求与造型设计的冲突，减少设计过程的反复。%The styling design of auto-body requires a design scheme of its free form headlamp quickly that is satisfied with illumination and lighting requirements .According to the principle of case-based reasoning (CBR) methodology ,this paper firstly studied the object-oriented case rep-resentation models for the free form headlamp .Then ,a headlamp case index model and matching algorithms were established according to the nearest neighborhood method of case retrieval and applying some preprocessing tools ,such as the headlamp bounding box and the layout reference frame .By representing the design knowledge and constraints of free form headlamp ,this paper built an appropriate case matching algorithms to obtain a design scheme for free form headlamp and presented case adaptation strategies ,combining dimension-driven with constrain satisfaction , to modify case solution fitting with the current problem definition . The application example showed the feasibility and practicability of the present methods on solving the conflict between engineering requirements and styling design .As a result ,these methods may introduce design re-quirements into the conceptual design stage of free form headlamp and quickly achieve appropriate design scheme .