Also known as material flow control, the material flow computer represents the interface between warehouse management system (WMS) and controller (PLC). It ensures not only the communication and thus the conversion of different telegram formats, but also the transport management. Here, it is worth mentioning especially the management of states, capacities and runtimes, the route optimization, target follow-up and, if necessary, also target selection, the control of non-continuous conveyors such as AS/RS - even entire high-bay warehouses and automatic small parts warehouses.
Here, the MFC is only software. However, we recommend using a physically separate computer, if the installation is sufficiently large and requires high outputs. The software consists of several processes running independently and event-triggered. The material flow control is based on a database, uses message queuing for inter-process communication and a shared memory to make states available to all processes by pure memory access. Thanks to a multi-tier concept, decision depths are structured leading to very fast responses (< 50 ms) when one target is provided. The MFC ensures also the error handling and routing - with information to the higher-ranking WMS to initiate any necessary countermeasures or substitute actions. The transfer of a transport order from the WMS (external solution Fresenius, Hoffmann, ...] or our DC21-WMS [Riegler, Rotho, Marburger Tapeten, ...]) is followed by the assignment of the transport routes, the use of resources and the reaction at the decision points and places. A TCP/IP handshake protocol is used for communicating with the PLC.