Facility-wide planning and scheduling of printed wiring board assembly

In the last decade, the US electronics industry has experienced a 10% annual growth rate in the assembly of printed wiring boards (PWBs). For many companies, this activity represents the most profitable component of their business with revenues in the billions for the industry as a whole. The basic functions associated with PWB assembly include inventory management, materials handling, production scheduling, and quality control, all of which are subject to a host of system-wide constraints. For the Texas Instrument facility in Austin, Texas, planning and scheduling is further complicated by the need to deal with over 10,000 different components and up to 400 different board types, each with their individual routing and bill of materials. This paper describes a decision support system known as Insites designed to assist Texas Instruments in the day-to-day assembly operations of their PWB facilities. The emphasis is on the heuristic techniques used to solve the underlying multiple machine scheduling problem and the efforts undertaken to validate and deploy the system. The identified benefits, coupled with the acceptance of Insites by both shop floor personnel and management, led the way to full system integration in early 1992.