Database Requirements of Knowledge-based Production Scheduling and Control: A CIM Perspective

A leitstand system is a scheduling and control station that plays the following role in computer integrated manufacturing. It receives information about production orders and resources from a MRP system (carrying out long and middle term production planning) and performs interactive or automatic finite capacity scheduling for the considered production resources (like machines, operators, tools, etc.). The exact schedule will be forwarded to the shop floor. During and after execution the resources report back to the lcitstand data about the actual performance. The leitstand can USC then the up-todate information about the actual status for rescheduling. An essential technical goal of KBL is to support easy customization for various production and system environments. This requires a flexible kriowledge representation. A leitstand is therefore a scheduling, control and information system based on knowledge and complex graphical information. Frequently, it is also a distributed system, when several leitstands have to cooperate. This results in many different requirements for a database system: