Knowledge-based workcell controller for production planning in the electronics industry

Abstract: The paper describes the analysis, design and implementation of a workcell controller using knowledge-based system technology in the electronics industry. The central task of the workcell controller is to bridge the gap between the high level production planning system of the logistics department and short-term planning at the shop floor level. Today the latter is mainly based on heuristic knowledge of a foreman. Due to the number of shop floor components involved and their rapid change the foreman is overloaded which leads to large stocks in the production and reduced flexibility. The production planning will be described as an optimisation problem optimising the degree of refinement of the production plan issued by the high level production planning system. As an analytical solution only based on operation research techniques is not feasible the proposed approach is to partly use the empirical knowledge of the foreman to reduce the solution space. To facilitate the formal specification of such combined approaches the optimisation process is presented using the terminology of production management systems (GRAI). The underlying CIM reference model is an extension of the NBS reference model towards the use of knowledge-based system technology.