Shop floor planning and control in integrated manufacturing systems

The implementation of a shop floor planning and control system is a prerequisite in establishing an effective computer integrated manufacturing system. A shop floor control system integrates management production goals with the capabilities and limitations of the manufacturing plant. Shop floor planning begins with a long term rough cut capacity plan and evolves into near term, capacity requirements and input/output plans. Shop floor control provides a status of in-process operations and a measure of the plants success in executing the plan. Effective use of technology on shop floor increases the efficiency of the manufacturing plant. Simulation is an important tools in accomplishing this. The use of simulation for planning and control of shop floor activities is a natural out growth of its application for the design of systems. Simulation, when used for production planning and control, is a useful vehicle for providing the discipline necessary for effective shop floor control in integrated manufacturing systems

IoT-enabled planning, control, and execution in ETO manufacturing: dynamics, requirements, and system architecture: a case study of Brunvoll AS

Confidential until 18. May 202

Resource selection and route generation in discrete manufacturing environment

When put to various sources, the question of which sequence of operations and machines is best for producing a particular component will often receive a wide range of answers. When the factors of optimum cutting conditions, minimum time, minimum cost, and uniform equipment utilisation are added to the equation, the range of answers becomes even more extensive. Many of these answers will be 'correct', however only one can be the best or optimum solution. When a process planner chooses a route and the accompanying machining conditions for a job, he will often rely on his experience to make the choice. Clearly, a manual generation of routes does not take all the important considerations into account. The planner may not be aware of all the factors and routes available to him. A large workshop might have hundreds of possible routes, even if he did know it all', he will never be able to go through all the routes and calculate accurately which is the most suitable for each process - to do this, something faster is required. This thesis describes the design and implementation of an Intelligent Route Generator. The aim is to provide the planner with accurate calculations of all possible production routes m a factory. This will lead up to the selection of an optimum solution according to minimum cost and time. The ultimate goal will be the generation of fast decisions based on expert information. Background knowledge of machining processes and machine tools was initially required, followed by an identification of the role of the knowledge base and the database within the system. An expert system builder. Crystal, and a database software package, DBase III Plus, were chosen for the project. Recommendations for possible expansion of and improvements to the expert system have been suggested for future development

Digital Design of Intralogistics Systems: Flexible and Agile Solution to Short-Cyclic Fluctuations

In times of fast-paced, fluctuating and individual markets, intralogistics systems, such as warehouses, have to adapt to the resulting volatile performance demands dynamically. Hybrid systems, in which humans and machines work together efficiently and communicate in socio-technical networks, can be the answer to manage these high-frequency markets. Hybrid systems of the future need to adapt frequently and permanent change becomes the “new normal”. A one-time planning of warehousing systems upon first installation becomes obsolete. This results in the question of how to design and implement processes for future logistics systems in an agile way in order to exploit the flexibility potential of hybrid services, which represent an interface between man, machine and organization. As part of the Innovation Lab Hybrid Services in Logistics in Dortmund, Germany, a research project funded by the German Federal Ministry of Education and Research, this research proposes a new concept for digital design of intralogistics systems that is meeting the requirements of a continuous, short-cycle adjustment following the Industry 4.0 development path

Mid-term capacity planning process and tool for textile services company

This development project was carried out for Lindström Oy. The purpose of the project was to do a needs assessment for medium-term purchase planning and develop a process for it. The goal also included comparing alternative software as a tool for the process. The process needs to bind the long-term plan forecast to the ongoing purchasing process. This will be done by using the plan as a base and updating the plan more often, in a weekly basis. The plan is updated and validated by the Mid-term Planner who is the only one making changes to the plan. The plan is then shared with the execution parties. The search for the application software was started from what are already in use at Lindström. These software are used in different levels of the purchasing and production planning. All systems are very different and all of them have very different strengths and weaknesses. None of the solutions were a perfect match and were unable to fulfill all the requirements set for the tool. There was not one clear winner, but one favourite was found

Improving lean design of production systems by visualization support

The design process of production systems is complex with many different aspects to consider for efficiently developing and installing an effective system. Important success factors during the design process are typically the abilities to identify and manage risks, develop mitigation plans, and conduct timely proactive problem solving. The work reported in this paper is part of research addressing methods for how the design process can be supported by using virtual representations of the factory environments captured with 3D laser scanning. This support is evaluated in an industrial study of one industrialization project in the manufacturing industry. The industrialization project follows the process to design layout, work places, and plan for installation of new equipment to create a production system within a refurbished shop floor area. The area will include CNC machining centers, welding stations, product inspection, product cleaning, and material handling. 3D laser scanning is used to provide an accurate and realistic virtual representation of the current shop floor area. This virtual representation is combined with 3D CAD models of the new machining centers and other equipment to provide a realistic visualization of the planned production system. The research approach and its questions investigate the benefits of combining the lean principles to design and development of production systems using a realistic visualization, which include systematic risk analysis and problem solving as important activities. The result shows that visualization support gave a great advantage to identify the possible risks and problems, which resulted in higher confidence and substantial timesaving in planning and execution of the industrialization project

Reconfiguring process plans: A mathematical programming approach

Increased global competition and frequent unpredictable market changes are current challenges facing manufacturing enterprises. Unpredictable changes of part design and engineering specifications trigger frequent and costly changes in process plans, which often require changes in the functionality and design of the manufacturing system. Process planning is a key logical enabler that should be further developed to cope with the changes encountered at the system level as well as to support the new manufacturing paradigms and continuously evolving products. Retrieval-based process planning predicated on rigid pre-defined boundaries of part families, does not satisfactorily support this changeable manufacturing environment. Since purely generative process planning systems are not yet a reality, a sequential hybrid approach at the macro-level has been proposed. Initially the master plan information of the part family\u27s composite part is retrieved, then modeling tools and algorithms are applied to arrive at the process plan of the new part, the definition of which does not necessarily lie entirely within the boundary of its original part family. Two distinct generative methods, namely Reconfigurable Process Planning (RPP) and Process Re-Planning were developed and compared. For RPP, a genuine reconfiguration of process plans to optimize the scope, extent and cost of reconfiguration is achieved using a novel 0-1 integer-programming model. Mathematical programming and formulation is proposed, for the first time, to reconfigure process plans to account for changes in parts\u27 features beyond the scope of the original product family. The computational time complexity of RPP is advantageously polynomial compared with the exponentially growing time complexity of its classical counterparts. As for Process Re-Planning, a novel adaptation of the Quadratic Assignment Problem (QAP) formulation has been developed, where machining features are assigned positions in one-dimensional space. A linearization of the quadratic model was performed. The proposed model cures the conceptual flaws in the classical Traveling Salesperson Problem; it also overcomes the complexity of the sub-tour elimination constraints and, for the first time, mathematically formulates the precedence constraints, which are a comer stone of the process planning problem. The developed methods, their limitations and merits are conceptually and computationally, analyzed, compared and validated using detailed industrial case studies. A reconfiguration metric on the part design level is suggested to capture the logical extent and implications of design changes on the product level; equally, on the process planning level a new criterion is introduced to evaluate and quantify impact of process plans reconfiguration on downstream shop floor activities. GAMS algebraic modeling language, its SBB mixed integer nonlinear programming solver, CPLEX solvers and Matlab are used. The presented innovative new concepts and novel formulations represent significant contributions to knowledge in the field of process planning. Their effectiveness and applicability were validated in different domains

Modeling, design and scheduling of computer integrated manufacturing and demanufacturing systems

This doctoral dissertation work aims to provide a discrete-event system-based methodology for design, implementation, and operation of flexible and agile manufacturing and demanufacturing systems. After a review of the current academic and industrial activities in these fields, a Virtual Production Lines (VPLs) design methodology is proposed to facilitate a Manufacturing Execution System integrated with a shop floor system. A case study on a back-end semiconductor line is performed to demonstrate that the proposed methodology is effective to increase system throughput and decrease tardiness. An adaptive algorithm is proposed to deal with the machine failure and maintenance. To minimize the environmental impacts caused by end-of-life or faulty products, this research addresses the fundamental design and implementation issues of an integrated flexible demanufacturing system (IFDS). In virtue of the success of the VPL design and differences between disassembly and assembly, a systematic approach is developed for disassembly line design. This thesis presents a novel disassembly planning and demanufacturing scheduling method for such a system. Case studies on the disassembly of personal computers are performed illustrating how the proposed approaches work

An Institutional Approach To Operations Management In Internet Based Production Concepts

An important change in the socio-economic environment of industrial firms is the increasing dif­fusion of Internet Technologies in production processes. Applications of Internet Technologies may be directly implemented on the shop floor, e.g. in networking dislocated assembly lines, as well as in assisting management processes, e.g. in production planning and control. This leads to a strong approximation of the traditional production and operation systems and the Internet Technologies. While traditional production concepts, such as Lean Production, World Class Manufacturing and Agile Manufacturing, inevitably disregard this development, new production concepts arise that fundamentally consider the application of Internet Technologies on the shop floor. However, from a business management perspective, industrial firms have to accomplish new operating requirements deriving from this technological change. This paper provides a discussion of the consequences of Internet Technologies on operations management, as well as of production concepts based on Internet Technologies from an institutional point of view