Simulation Study of Flexible Manufacturing Cell Based on Token-Oriented Petri Net Model

Abstract

An initial manufacturing plan may not consider the particular implementation of flexible manufacturing cells (FMCs). Therefore, the FMC is subject to modelling and simulation to evaluate and correct the production plan using feedback. In the case of highly shared resource contention, deadlock and blocking present an inevitable, unavoidable problem, and corrections may be required for production plans. However, by using existing Petri net model theories and certain simulation software for model establishment, the structure and scale of the model may vary with changes in the parts, machines, and robots. This results in a cumbersome and complicated model building process. To address this practical problem, a token-oriented Petri net model theory is therefore proposed. The movable directions of a token are detected to determine if the firing conditions are satisfied. To avoid deadlock, the token first predicts the status of resource utilization prior to decision-making when entering the transporting-transition state. Accordingly, during the model run, events are triggered against the expected time, and transitions are thereby enabled and fired. An improved machine processing plan and robotic transporting plan may be obtained via path scenario deduction. In this study, classic case data were processed for simulation analysis of the manufacturing job, which verified the validity of the model algorithm.

A New Model for Optimization of Cell Scheduling Considering Inter-Cell Movement

“…According to [14], a CMS has an average of 5.9 cells, and each cell contains an average of 6 machines. So, the ranges of Number of cells, Number of machines in each cell and Number of parts in each cell are (3,4,5), (5,6,7,8) and (8,12,20,30) respectively. Random cases were generated to verify the effectiveness of the HWHS solution since there is no standard case to use.…”

“…Shi et al [3] established a dynamic scheduling model for the flexible job-shop scheduling problem considering fuzzy delivery time. However, along with the changing needs of customers, cellular manufacturing (CM) has been widely used to produce small-and medium-batch products with high personalization and complexity, and the scheduling problem for manufacturing cells has been widely considered [4][5][6][7].…”

Two-Machine Robotic Cell Sequencing under Different Uncertainties

“…A large stand-alone library helps users to pick up the most appropriate elements for modelling the desired layouts easily. In the literature, there are some studies on the use of simulation in manufacturing systems such as [31][32][33][34] and so on. Also, as an appropriate document in application category, a comprehensive review of articles involving simulation in manufacturing between 2002 and 2013 has been provided in [35].…”

Case Study for Planning of Cell Production System

“…This results in a cumbersome and complicated model building process. To address this practical problem, a token-oriented Petri net model theory is therefore proposed by Nie et al [16].…”