Development of Knowledge Acquisition and Automatic Layout System for Printed Wiring Board Design

我们开发了一个自动排版系统，它从熟练的设计师的图纸中获取排版知识，并利用它来获得满意的排版效果。熟练设计师布局策略的特点在于“聚类”（电路划分）、“聚类布局”和基于总线的方法。我们的系统从熟练的设计师的布置图中获取聚类和聚类放置的知识，并根据已经确定的规则检查矛盾。在每条规则的条件部分，引入一个带有预测变量的线性不等式来判断所选择的候选对象是否适合作为对象。由于线性不等式中的系数和常数是采用判别函数方法自动确定的，因此可以解决不同棋盘规则之间的冲突。因此，随着知识获取所使用的电路板数量的增加，系统布局结果与手工设计的相似度也随之增加。此外，我们还开发了一种用于总线网络路由的分层路由方法，并考虑了包括未路由网络在内的所有网络的影响。对于路由算法的高速处理，我们评估了几种多处理架构，结果表明，包含树形网络的超立方体类型架构是最适合实现的。

We have developed an automatic layout system, which acquires layout knowledge from skilled designers' drawings and makes use of it to get satisfactory layout result.Characteristic points in skilled designers' layout strategies are in "clustering" (circuit partitioning), "cluster placement", and bus based methods. Our system acquires knowledge for clustering and cluster placement from skilled designers' layout drawings, and checks contradictions with already fixed rules. In the condition section of each rule, a linear inequality with predictor variables is introduced to judge whether the selected candidates are suitable as an object. Since the coefficients and constants in the linear inequality are determined automatically employing the discriminate function method, conflict resolution between rules from different boards are performed. As a result, the similarity between the system layout result and the manual design has increased according to the number of boards used for knowledge acquisition.Furthermore, we have developed a hierarchical routing method for bus net routing and for taking influences of all nets including unrouted nets into consideration. For high speed processing of the routing algorithm, we have evaluated several multiprocessing architectures, and the hypercube type architecture including tree network has turned out to be the best for implementation.