THE VIRTUAL MANUFACTURING CELL

Abstract

A virtual manufacturing cell is being developed at the National Bureau of Standards as part of the control software for the Automated Manufacturing Research Facility (AMRF) project. The traditional group technology (GT) cell has evolved from the need to maintain the flexibility to manufacture a family of parts while gaining some of the efficiency associated with a single process flow line. GT cells are normally defined by a fixed physical grouping of machining workstations that produce a particular class of parts. A shop based upon virtual manufacturing cells provides greater flexibility than existing GT shop configurations by time sharing machining workstations. Virtual GT cells are not identifiable as fixed physical groupings of machinery, but as data files and processes in a control computer. Functions performed by these processes include analysis, reporting, routing, scheduling, dispatching, and monitoring. At a higher level, the shop control system schedules cell activation and allocates workstations and other resources to these cells. Workstations are at all times under the control of either a particular virtual cell or a pool cell composed of idle workstations.