Class Of Manufacturing Systems Research Articles

Reconfigurable manufacturing system – a new class of manufacturing system

Reconfigurable manufacturing system – a new class of manufacturing system

Manufacturing Systems Suitable for Globalized Market

The paper clarifies the reasons leading to the creation of a new class of manufacturing system from a global perspective, focusing on the market environment. It describes the needs for reconfigurable manufacturing systems, which allows coping with market requirements and changes quickly and costing effectively. The article provides the approach to the design of the reconfigurable manufacturing systems from system, machine and control level point of view.

A real-option approach to flexibility planning in reconfigurable manufacturing systems

Reconfigurable manufacturing systems (RMS) are a new class of manufacturing systems aiming at combining the high throughput of dedicated manufacturing lines with the flexibility of flexible manufacturing systems. An RMS can simultaneously manufacture a large variety of product types in unpredictable quantities while maintaining mass production efficiency. Flexibility typically comes at a price and is only valuable as a hedge against environmental uncertainty. It is important to determine an appropriate level of flexibility in the reconfiguration of production systems while considering the tradeoffs between its costs and benefits. This paper develops a real-option theoretical model that provides insights into flexibility planning in an RMS. A practical method is presented to assist the justification of an RMS in deciding how to influence its operating environment and choose right reconfiguration technologies in order to maximize the performance measure of profitability. The real-option approach surmounts traditional discounted cash-flow-analysis-based valuation methods that tend to ignore the upside potentials of an investment from management flexibility. The proposed model is tested with a real-life RMS installed for the Printed Circuit Board (PCB) assembly of mobile phones with a high level of variety.

Feedback control designs for manufacturing systems modelled by continuous Petri nets

This work is concerned with the control design of a certain class of manufacturing systems modelled by continuous time Petri nets. The considered systems are large series assembly workshops for which the final machine is a mono-input mono-output one. The average production frequencies of the machines are controlled according to the buffers' content. Three different feedback control designs are investigated: a bang-bang one, a proportional one, and a combined one. The convergence of the output buffer to a desired level is proved, and the analytic expression of the marking is detailed in the case of a single machine station. The results are then applied for the control design of open manufacturing lines.

Priority analysis of patrolled machines

A class of manufacturing systems is presented in which the machine interference problem plays a major rule. We consider a single server (robot) plus two types of random machines stoppages with priorities. A detailed analysis of trasition probabilities and their steady-state behavior is provided. Several typical examples are worked out to illustrate the analytical development.

Modelling of Manufacturing Systems with Machines Failure Using Neural Networks

Abstract In this paper we make a modelling of a class of manufacturing systems using neural networks. The evolution of the considered systems is supposed to be continuous. The capacities of the buffers are not limited and the machines present the problem of failure. The system's elements (buffers & machines) are modeled separately and connected together in order to obtain a global net that simulates in a general way the behaviour of the real system.

Sensitivity analysis of machine interference in manufacturing systems

A class of manufacturing systems is presented in which the machine interference problem plays an important role in production. We consider a single server (robot) in addition to two types of random machine stoppages with priorities. A detailed analysis has been focused on two measures: robot utilization and machine efficiency. It has been shown that one has to make a compromise between the above two sensitive measures. We have further computed the optimum number of machines that can be served by a robot. A novel optimization technique is used to fulfill this requirement. The simulation results reveal that the number of machines as well as the service rate can be utilized as decision variables in the problem at hand.

Sensitivity analysis of machine interference in manufacturing systems

A class of manufacturing systems is presented in which the machine interference problem plays a major role. We consider a single server (robot) plus two types of random machine stoppages with priorities. A detailed analysis of the transition probabilities and their steady-state behaviour is provided. Several typical examples are worked out to illustrate the analytical development.

A maximum principle based combined method for scheduling in a flexible manufacturing system

A continuous time dynamic model of discrete scheduling problems for a large class of manufacturing systems is considered in the present paper. The realistic manufacturing based on multi-level bills of materials, flexible machines, controllable buffers and deterministic demand profiles is modeled in the canonical form of optimal control. Carrying buffer costs are minimized by controlling production rates of all machines that can be set up instantly. The maximum principle for the model is studied and properties of the optimal production regimes are revealed. The solution method developed rests on the iterative approach generalizing the method of projected gradient, but takes advantage of the analytical properties of the optimal solution to reduce significantly computational efforts. Computational experiments presented demonstrate effectiveness of the approach in comparison with pure iterative method.