For different kind of research and educational projects the Laboratory of Information and Computer Systems in Automation have purchased a flexible production system manufactured by GWS. This kind of system is widely in use in electronic industry production lines. The system consists of two lifter units in both ends of the system, a starter unit and a workstation unit. Programmable logic controllers handle the controls of the units, so that each module of the system is totally independent unit.
In the lifter unit a pneumatic lifter lifts palettes up to main conveyor or down to return conveyor one palette at time. In the modules of starting and workstation units there are three parallel conveyors, between which palettes are transferred by means of a crossing conveyor. Workstation modules take in palettes according to the work phase code. Palettes are send away from the workstation modules and new codes are written to the escort memory of the palette. The locations of palettes are detected with inductive and optic sensors.
The modules are connected to an Interbus fieldbus. This makes it possible to supervise the state of the system. The fieldbus is connected parallel to PLC I/O points and therefore units can be controlled using a computer running a SoftPLC system.
There is also room for future development. The workstations could be automated using machine vision applications, sophisticated sensor technology and robot manipulators. Higher level tasks like pallet routing can be planned and developed.