Multi-objective Production Planning for a Flexible Manufacturing System based on NSBBO Method

The dramatic expansion in the global manufacturing market has created a demand for small and medium enterprise (SME) to apply the advanced manufacturing technology (AMT). The flexible manufacturing system (FMS) is considered as a highly competitive manufacturing strategy to ensure the success of the enterprises in the developing countries. The implementation of FMS, however, is an intractable task that requires complete integration of numerous components from various vendors. This paper presents a multi-objective production planning model for selecting the most suitable combination of machines and operations in machining processes to simultaneously minimize the system unbalance, makespan (MK) and total flow time. The proposed model considered the capacity of machines, tool magazines, batch sizes, processing time and the time taken to transport machining parts. Moreover, it also considered the different allocation of each part of batch into various machines. The principle of biogeography-based optimization (BBO) is adapted to explore the possibilities of attaining feasible solutions for a formulated problem. The most appropriate solutions in selecting the machine and operation allocation were determined based on non-dominated sorting BBO procedure (NSBBO) and validated by FlexSim simulation environment. The obtained results highlighted the practical applicability in the implementation of FMS.

Synthesis and Implementation of Reconfigurable PLC on FPGA Platform

Synthesis and Implementation of Reconfigurable PLC on FPGA PlatformThe paper presents a set of algorithms dedicated for synthesis of reconfigurable logic controllers implemented on FPGA platform and programmed according to IEC1131 and EN61131. The program is compiled to hardware structure with a massive parallel processing. The developed method automatically allocates resources and operations. It controls resource usage and operation timing. Using mixed concept of operation allocation that considers operation timing and forms combinatorial chains of operations number of execution cycles can be reduced. An example of logic functions, PID controller and mixed arithmetic and logic programming examples are considered. Introducing the automatic implementation method allows flexible implementing the control algorithms. The maximal possible parallelism (limited only by the algorithm dependencies and available resources) is introduced.