Modular control of a reconfigurable conveyor system

[摘要] ENGLISH ABSTRACT: This thesis documents research into the control of a reconfigurable conveyersystem. The conveyer forms part of a reconfigurable assembly system. The mainreason for research into reconfigurable systems is the need in the modernmanufacturing industry for systems to be adaptable to changing product designs.Modern manufacturing requires many short production runs of different products,instead of the traditional long term production run of a standard product.The objective of this thesis was to design and implement a controller for areconfigurable conveyer system. The conveyer hardware was fixed, but thecontrol system had to be developed. A distributed control architecture was chosen.The conveyer was sectioned into different modules, and each module wascontrolled by a separate controller. This modularity enhanced the conveyer'sreconfigurability properties.The control was split into two sections, low level control (LLC) and high levelcontrol (HLC). LLC was responsible for the actuation of the conveyer's hardware,using programmable logic controllers (PLCs). The HLC did more advanced taskssuch as communication, task management and path planning.The software design was based on a modified ADACOR holonic architecture. Theholonic architecture was used because it promotes reconfigurability. Path planningwas done using Dijkstra's algorithm.Experimental results show that the conveyer was able to successfully handlemultiple pallets. A reconfiguration test was done, which showed improved resultsfrom previous work. The design mostly exhibits the characteristics ofreconfigurability, which are modularity, customizability, scalability, integratibiltyand diagnosability.

[发布机构] Stellenbosch University