Coding methods for automatic placement of parts on printed circuit boards

Abstract

There have been growing demands for automatic placement of parts on printed circuit boards (PCBs). Since the parts have wide variety in size and these parts should be placed under various constraints, the automatization of parts placement is a very difficult task. The authors proposed a method using the genetic algorithm (GA) for the automatic placement on highly dense PCBs. The study was, however, done on an imaginary board. Many factors, such as gaps between parts, lining up of parts of same type, etc. were not considered. This paper presents three new coding methods for the automatic placement on the PCBs. The three proposed methods incorporate rotating angle of parts, gaps between parts, forming of parts of same type in lines as well as dense placement of parts. Actual PCBs are used for showing and comparing the effects of the new coding methods. The results show that the proposed methods are feasible for the automatic placement of parts on highly dense PCBs. © 1995, The Institute of Electrical Engineers of Japan. All rights reserved.