Control System for Path-Configurable Transportation Line for Large Cargo Handling

A control system for path-configurable transporting and multi-site processing line for large cargos was developed. The system can maintain the information of the cargos synchronizing with the cargos which were transported in different paths. Generic PC/PLC-based two-layered hardware architecture was adopted. Pipe and filter model was employed in the PLC control software as its architecture. Pipe and filter model was adapted at its sublayer according to object-oriented method to ease the implementation of a real-time multitask control system. The filters which were used to control the conveyors were designed as objects. One filter, which is the control center of the filters, was designed to dispatch the commands and information to the controller objects. The commands and information were transferred between the controller objects by messages. In the system, a set of PLC was employed to control a group of conveyors, which were working independently and concurrently, thanks for the software architecture. The adapted architecture can be reused as a framework of control software for distributed flexible transport systems.