Real time scheduling and control of manufacturing cells

This paper presents a new control structure and a scheduling method which can effectively deal with disruptions in a manufacturing environment. The structure consists of a scheduler and a supervisor module. The control structure effectively deals with part movement, material handling, machine breakdowns, error handling, scheduling concerns. The scheduler consists of a fuzzy logic scheduling method which addresses a wider range of scheduling issues than those considered by most dispatching rules, contains mechanisms for optimization and is easily expanded. The control structure was developed using the object oriented paradigm in a manner which mimics the real world shop floor effectively and allows for the easy generation of more parts, machines, and tools. Overall, the control structure and the scheduling algorithms have proven to be flexible, expandable and easily optimized