Green and lean control of cyclic pallet systems

Reduction of energy consumed by a manufacturing system to turn raw parts to finished products is a big step towards the green and lean production. In this study the energy efficiency of a one-loop pallet system, a main tool to handle and locate various part types in a cyclic production line, is investigated. The main goal is to obtain the minimal energy consumption in the pallet system drive unit through an optimally controlled and coordinated motion of pallets. To achieve the mentioned goal, first the mean value of the pallet system energy consumption is mathematically modeled. Later, this energy model is utilized as an objective function within an optimization model including constraints on system crucial properties such as cyclic and dynamic behavior, queueing policy, and buffer size. The solution of the optimization problem gives the optimal values of the system control variables, namely, number of pallets and conveyor velocity. To demonstrate the application of this optimization model in practice, three case studies are introduced. The results of these studies show that a significant amount of the energy consumption may be saved by applying the suggested green control

Sustainable and robust Control of Cyclic Pallet Systems

A proper control of a system to get a desired function and increase the system lifetime is a crucial step towards the sustainable paradigm. In this paper, such a control is designed for a cyclic pallet system to achieve a minimal force on its drive unit, meet safety conditions on the system chain tension force and the momentum of pallets, and fulfill the desired production rate. The optimal values of the control parameters, namely number of pallets and conveyor velocity, are obtained through solving a linear optimization model. The objective function in the model defines the average force on the drive unit in a cycle production. In addition, the related constraints characterize the pallet system properties such as cyclic and dynamic behavior, buffer size, constant work in process, and safety specifications. The robustness of the optimal control is analyzed, using a worst but safe control strategy. The optimal control and the robustness analysis are applied to some case studies, and the results are evaluated and discussed

Concurrent Design and Control of Automated Material Handling Systems

Lean and agile design and control of an automated material handling system are investigated in this paper. The demands for a minimal number of handling resources and their maximal utilization emphasize the importance of a concurrent structure and control design for a handling mechanism in the conceptual phase. To provide this concurrency, a universal model based on mathematical linear constraints is developed to define a set of part movements without concerning a specific handling technology. Furthermore, an objective characterizing optimal part movements, according to the lean and agile paradigms, is formulated in the conceptual design phase. Control measures, which are obtained by solving the mixed integer linear model including the objective and constraints, provide important keys for designers to conceptualize a proper design of an automated material handling system. To show the application of developed approach, a case study is presented and discussed

A Universal Framework for Lean Design and Control of Automated Material Handling Systems

Lean design and control of an automated material handling system is investigated in this study. A universal framework for modeling and analysis of different types of material handling mechanisms is introduced to obtain a minimum number of resources in a system design and fulfill a desired throughput. This framework is developed in a discrete event simulation environment and applied to a case study based on a real pallet system technology. The minimal design of the pallet system is realized by devising the system universal model

Technology for large space systems: A special bibliography with indexes (supplement 05)

This bibliography lists 298 reports, articles, and other documents introduced into the NASA scientific and technical information system between January 1, 1981 and June 30, 1981. Its purpose is to provide helpful, information to the researcher, manager, and designer in technology development and mission design in the area of the Large Space Systems Technology (LSST) Program. Subject matter is grouped according to systems, interactive analysis and design, structural concepts, control systems, electronics, advanced materials, assembly concepts, propulsion, solar power satellite systems, and flight experiments

Technology for large space systems: A bibliography with indexes (supplement 16)

This bibliography lists 673 reports, articles and other documents introduced into the NASA scientific and technical information system between July 1, 1986 and December 31, 1986. Its purpose is to provide helpful information to the researcher, manager, and designer in technology development and mission design according to system interactive analysis and design, structural and thermal analysis and design, structural concepts and control systems, electronics, advanced materials, assembly concepts, propulsion, and solar power satellite systems

Technology for large space systems: A special bibliography with indexes (supplement 04)

This bibliography lists 259 reports, articles, and other documents introduced into the NASA scientific and technical information system between July 1, 1980 and December 31, 1980. Its purpose is to provide information to the researcher, manager, and designer in technology development and mission design in the area of the Large Space Systems Technology Program. Subject matter is grouped according to systems, interactive analysis and design. Structural concepts, control systems, electronics, advanced materials, assembly concepts, propulsion, solar power satellite systems, and flight experiments

Technology for large space systems: A bibliography with indexes (supplement 12)

A bibliography listing 516 reports, articles and other documents introduced into the NASA scientific and technical information system between July 1, 1984 and December 31, 1984 is presented. Its purpose is to provide helpful information to the researcher, manager, and designer in technology development and mission design in the area of Large Space System Technology. Subject matter is grouped according to system, interactive analysis and design, structural and thermal analysis and design, structural concepts and control systems, electronics, advanced materials, assembly concepts, propulsion, and solar power satellite systems

Technology for large space systems: A bibliography with indexes (supplement 20)

This bibliography lists 694 reports, articles, and other documents introduced into the NASA Scientific and Technical Information System between July, 1988 and December, 1988. Its purpose is to provide helpful information to the researcher or manager engaged in the development of technologies related to large space systems. Subject areas include mission and program definition, design techniques, structural and thermal analysis, structural dynamics and control systems, electronics, advanced materials, assembly concepts, and propulsion