An interactive scheduler for production activity control

Abstract

Traditionally, scheduling research has concentrated on the classical n machine/m job problem. Many of the algorithms and scheduling systems developed can produce optimal or near-optimal solutions to well-defined scheduling problems. However, often there are so many assumptions made in the process thai, in the complex environment of the typical shop floor, the solutions proposed are of little practical value. Their inability to lake into account real-life problems such as butch splitting, machine breakdown and maintenance, material availability etc., means that unrealistic schedules often result. This paper recognizes these complexities, not by attempting to design a totally automated scheduling system, which for the reasons described is impractical in most cases, but by including human interaction as an integral part of the solution strategy. Accordingly, the principles of socio-technical design have played an important part in the development process. The result of this developmeni, the interactive scheduler, is a decision support system that attempts to achieve a balance between available computing power and human intuition and experience, the Corner to alleviate the more mundane and tedious scheduling tasks and the latter to provide the intelligent input necessary to generate a solution. This solution will seldom be optimal, but it will usually model a given manufacturing system more closely than a schedule produced automatically, since the user has played an explicit part in its development.