A Collaborative Process Planning and Scheduling System

Traditionally, process planning and scheduling have been rather separate activities within a company. Nowadays, the need for more flexible production and shorter production lead times urges for a close collaboration between these activities as a first step towards simultaneous engineering. This article describes the results of the ongoing ESPRIT Project COMPLAN, which aims at the implementation of an integrated automatic process planning and scheduling system based on the concept of non-linear process plans. Additionally to the use of NLPP for flexible load balancing and re-active rescheduling, a new collaborative approach is presented that is based on production constraints as a means to realise a feedback from scheduling to process planning. A process planning kernel is described that integrates this concept of production constraints.