Agile manufacturing system with autonomously operated square arrayed machining cells

Development of a Flexible and Agile Multi-robot Manufacturing System

Manufacturing system effectiveness depends on several factors which include qualitative as well as quantitative factors. In the present paper, the management of the case company has to take a decision about the prioritisation of manufacturing systems on the basis of their effectiveness and has to decide about their production capacity. In the available literature, approaches like linear programming and AHP, mixed integer linear programming, and goal programming have been applied by some authors to tackle similar type of problems. These techniques are mathematical in nature and also consider qualitative factors which are crucial in determining the effectiveness of any manufacturing system, particularly when manufacturing systems are to be prioritised. The result from the research work with AHP framework indicates higher manufacturing effectiveness to leagile manufacturing system followed by agile manufacturing system, lean manufacturing system and flexible manufacturing system.

In reaction to the necessity, the manufacturing processes evolved from mass production technique, through its implementation on agile manufacturing system (AMS). The most complicated part of AMS is an understanding of the barriers and evaluates the performance for each barrier. This article presents an intangible framework of various barriers associated with AMS along with their performance. Using fuzzy performance importance index (FPII) approach, the barriers of AMS presented in the form of a single numerical index value. The proposed model is relatively adaptable from the point of analysis that it provides a prospect to integrate new barriers which could impact on manufacturing processes. In the present work, an effort has been made to develop a mathematical model of these barriers using FPII approach. An index value for each of AMS barriers is proposed which calculate the inhibiting power of these barriers.

In this chapter, we describe the case study of a real-time database system for a specific kind of operational data generated by an agile manufacturing system. The term agile manufacturing refers to a manufacturing system that can fabricate various products simultaneously without long downtimes for retooling. The agile manufacturing increases competitiveness of companies in the market by decreasing the downtime and reconfiguration overhead incurred due to product changes. The agile manufacturing concept is already in a stage of practical use in some companies, for example, pager manufacturing at Motorola [19], or customized bicycles from Panasonic [5].

To quickly satisfy customer needs and to respond to market changes it is eminent to develop agile manufacturing systems. These have to support integration of flexible and reconfigurable production systems as well as IT technologies across the entire value chain. While implementing advanced technologies or integrating these into new system solutions, manufacturers and system developers have to understand the current and the desired technological capabilities of the system application. Before constructing a robust technology backbone for agile manufacturing systems, it is therefore important to make a clear picture of existing standardized solutions. Though a vast variety of assessment techniques is presented in literature, it is still unclear which approach is appropriate for a technology gap analysis, especially when developing agile manufacturing system solutions. Therefore, the harmonization of assessment techniques is essential for the analysis of the technological compliance among various systems. This paper presents a harmonized approach with exemplary results in order to navigate system developers and stakeholders towards effective and robust technology solutions that are compliant with Industry 4.0 goals and independent of manufacturing application fields.

This paper provides a literature review study to investigate how Agile Manufacturing (AM) capabilities could be used in different plants within a company's Global Production Network (GNP). To do this, this paper makes use of Ferdows, Vereecke, and De Meyer (2016) subnetworks positions framework. Each of the subnetwork positions has its own manufacturing characteristics and missions. From the four subnetworks, this paper focused on the main two, footloose and rooted. 17 articles were analyzed and this paper found that there are four major AM capabilities categories, namely responsiveness, flexibility, integration, and competency. Each of the AM capabilities categories could be used differently in each of the subnetworks depending on the focus factors emphasized in each category. With that, this paper has presented how AM system capabilities could help plants in the footloose and rooted subnetworks to achieve their missions. Further, this study provides an early phase to understand how AM system could accommodates different plants positions in the GPN. This study also set out an insight that, despite being founded 29 years ago, AM system with their capabilities, is still relevant to be continuously implemented in the present time. This paper does not provide any empirical validation yet for the findings. Thus, this paper also provide avenues for future research.

We present two aspects of knitting technique, the structural properties (especially the P- and T-invariants), and the synchronized choice net (a new class of Petri net), that are of both theoretical importance and practical uses to the verification of structural correctness of a Petri net or to detect the structural problem of a Petri net. This work first proves that the ordinary Petri nets synthesized with knitting technique are structurally bounded, consistent, conservative and safe (when each home place holds one token) using the well-known linear algebra approach. It also provides a procedure for finding P- and T-invariants for Petri net synthesized using the knitting technique. We present examples for P-invariants and show that we can synthesize Petri nets more general than the "asymmetric-choice nets". The algorithm for finding P-invariants of ordinary Petri nets is extended to find the P-invariants for a general Petri net synthesized with knitting technique and the arc-ratio rules. We present a new class of Petri nets, called synchronized choice nets, which are the largest set of Petri nets that can be covered by both T-components and P-components. An algorithm is proposed to find its T-components and the P-components, respectively. The complexity of this algorithm is also presented. The theory of synchronized choice nets has the potential to simplify that for free choice nets.

A new heuristic search approach for scheduling two classes of flexible manufacturing systems (FMSs) that contains assembly operations is proposed. The FMSs are modeled by two classes of Petri nets, called generalized symmetric and asymmetric nets. In the paper, the problem of minimizing makespan is transformed into searching the reachability graph for the optimal (minimal time) firing sequence from the initial marking (state) to the goal marking. A solution of the state equation constitutes a part of the heuristic function. The dynamic information of the nets, such as concurrency and synchronization, is used to adjust the heuristic function since the solution of the state equation may over-estimate the real cost.

Combined Petri net modelling and AI based heuristic hybrid search for flexible manufacturing systems—part 1. Petri net modelling and heuristic search

Leagile manufacturing strategy has emerged as one of the important strategy adopted by most of manufacturing organizations now a days. It has advantages of both lean as well as agile manufacturing system. Lean manufacturing tries to eliminate all different types of wastages like overproduction, inventory, unnecessary motion etc., while agile manufacturing focus on changing the production system as per the requirements of the customer and provide customized products within short span of time. Lean manufacturing focuses on no inventory and try to implement Just in Time methodology but for the system to be agile, there should be at least some inventory in store so that production can be started as soon as customer order is achieved. In this paper, key performance indicators (KPI) of leagile manufacturing are found by literature review and in consultation of experts and academicians working in the concerned field. Fuzzy TISM approach has been applied to find levels of different KPI’S. MICMAC analysis has been made to analyze the KPI’S and categorize them as autonomous, dependent, linkage, independent etc. on the basis of driving and dependence power. Finally, digraph is drawn to show relationship between various KPI’s.

Timed marked graphs, a special class of Petri nets, are extensively used to model and analyze cyclic manufacturing systems. Weighted marked graphs are convenient to model systems with bulk services and arrivals. We consider two problems of practical importance for this class of nets. The marking optimization problem consists in finding an initial marking to minimize the weighted sum of tokens in places, while the average cycle time is less than or equal to a given value. The cycle time optimization problem consists in finding an initial marking to minimize the average cycle time, while the weighted sum of tokens in places is less than or equal to a given value. We propose two heuristic algorithms to solve these problems. Several simulation studies show that the proposed approach is significantly more efficient than existing ones.

Drivers for the adoption of integrated sustainable green lean six sigma agile manufacturing system (ISGLSAMS) and research directions

The paper faces the reachability and the reversibility problems in a class of Petri nets larger than other classes investigated for the same problems. The considered class of Petri net represents a formal language to design and analyze logic controllers. These nets may be decomposed in simple structures, called elementary control tasks, linked together through a limited number of connections, giving rise to arbitrarily complex nets. Such connections are the ones encountered in a typical logic control problem, as exchange of enabling signals (consensus/deny to control maneuvers) and the synchronous execution (shared resources modeling or shared operations). The purpose of the paper is to enlarge the set of theoretical tools previously developed for the incremental approach to the liveness analysis of a net, to be incorporated into a special CAD environment. In particular, the addressed topics are the choice of the initial marking and the analysis of reachability of nonlive markings.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

This paper presents an intelligent defect management system based on cyber-physical systems that orchestrate computational resources with physical systems in the specific environment of porcelain manufacturing. Sensors and computer vision techniques detect defects and faults, an intelligent information processing system based on ontologies and deep learning methods quantify different types of defects in porcelain products and provide information to the decision making system and actuators in the workflow. The system is developed within a project in collaboration with one of the biggest porcelain ware producer in Europe. It focuses on defect causation analysis and provide an advanced management system aiming to facilitate defect measures and rectifications by: (1) collecting and classifying defect data; (2) identifying causations of defect and analyzing its impact; (3) searching and managing defect information by means of knowledge management (KM) techniques, namely ontologies; and (4) developing agile defect control of porcelain ware. The final goal and result of the project is to achieve an intelligent and agile manufacturing system.

Selecting the most agile manufacturing system with respect to agile attribute-technology-fuzzy AHP approach