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Describes a 1995 market survey of 21 UK vendors and users of cell control systems. The market data were collected via the use of a questionnaire which elicited views on…
Describes a 1995 market survey of 21 UK vendors and users of cell control systems. The market data were collected via the use of a questionnaire which elicited views on: functional requirements of cell controllers; benefits realized through applying cell control technology; operational requirements of cell controllers; factors which constrain the industrial use of cell control technology; and the scale of the cell controller market. The results provide a useful indication of the current size of the UK cell control marketplace and the main areas in which such systems have been successfully applied. They also outline a set of outstanding industrial requirements, knowledge of which can help shape the agendas of research and vendor communities which currently seek to develop the next generation of cell control systems.
– This paper aims to describe a new methodology for controlling highly flexible automated manufacturing cells for use in aerospace manufacturing and repair.
This paper aims to describe a new methodology for controlling highly flexible automated manufacturing cells for use in aerospace manufacturing and repair.
The design methodology and rational of the FLEXA control architecture are described along with it implementation and testing.
The trials completed so far show that the level of flexibility required can be achieved both at factory, or enterprise level, and at shop floor level.
This work has significant practical implications through its direct applicability for aerospace and other automated manufacturing processes.
The originality of the paper lies in the truly flexible nature of the control system described and its ability to mimic traditional cell control architectures but be expanded through the use of virtual Programmable Logic Controller to control any number of cells without the need for significant extra hardware.
Rework is an integral part of printed circuit board assembly (PCBA) manufacturing. However, the state‐of‐the‐art for PCBA rework still relies on operator activity and is…
Rework is an integral part of printed circuit board assembly (PCBA) manufacturing. However, the state‐of‐the‐art for PCBA rework still relies on operator activity and is therefore semi‐automatic. As a result, the quality of rework depends very much on the skill of the operator. When developing an automatic PCBA rework cell, the cell controller is an essential part which organises and controls the overall rework operation. This paper describes the software modelling of the cell controller for the PCBA rework cell which has been implemented for reworking through‐hole and surface mounted components. The software model is based on hybrid representations and rule‐based control.
The use of computers on the shop floor has been slight compared with their widespread acceptance at higher levels in the manufacturing environment. Today, there is an urgency to redress this imbalance by investing in modern production facilities, but progress is being restricted by the void between the operational requirements of the upper and lower levels. The Discrete Cell Controller (DCC) is considered to be capable of satisfying this role. This article considers the measures taken by a consortium of industrial and academic partners to determine the specification of a DCC and, in particular, identify the generic content.
The mobile software agent paradigm provides a generic, customisable foundation for the development of high performance distriubuted applications. An efficient…
The mobile software agent paradigm provides a generic, customisable foundation for the development of high performance distriubuted applications. An efficient, general‐purpose access control mechanism is required to support the development of a wide range of applications. This is achievable if the design of the access control system is based on the principles of simplicity, programmability (customisation) and reusability. However, existing mobile agent architectures either neglect this issue, or offer centralised schemes that do not support adaptive access control on a per‐agent basis and do not address the issues of secure knowledge sharing and reusing. In this paper a simple, distributed access control architecture is presented, based on the concept of distributed, active authorisation entities (lock cells), any combination of which can be referenced by an agent to provide input and/or output access control. It is demonstrated how these lock cells can be used to implement security domains and how they can be combined to create composite lock cells.
The purpose of this paper is to optimize the design and power management control fuel cell/supercapacitor and fuel cell/battery hybrid electric vehicles and to provide a…
The purpose of this paper is to optimize the design and power management control fuel cell/supercapacitor and fuel cell/battery hybrid electric vehicles and to provide a comparative study between the two configurations.
In hybrid electric vehicles (HEVs), the power flow control and the powertrain component sizing are strongly related and their design will significantly influence the vehicle performance, cost, efficiency and fuel economy. Hence, it is necessary to assess the power flow management strategy at the powertrain design stage in order to minimize component sizing, cost, and the vehicle fuel consumption for a given driving cycle. In this paper, the PSO algorithm is implemented to optimize the design and the power management control of fuel cell/supercapacitor (FC/SC) and fuel cell/battery (FC/B) HEVs for a given driving cycle. The powertrain and the proposed control strategy are designed and simulated by using MATLAB/Simulink. In addition, a comparative study of fuel cell/supercapacitor and fuel cell/battery HEVs is analyzed and investigated for adequately selecting of the appropriate HEV, which could be used in industrial applications.
The results have demonstrated that it is possible to significantly improve the hydrogen consumption in fuel cell hybrid electric vehicles (FCHEVs) by applying the PSO approach. Furthermore, by analyzing and comparing the results, the FC/SC HEV has slightly higher fuel economy than the FC/B HEV.
The addition of electrical energy storage such as supercapacitor or battery in fuel cell‐based vehicles has a great potential and a promising approach for future hybrid electric vehicles (HEV). This paper is mainly focused on the optimal design and power management control, which has significant influences on the vehicle performance. Therefore, this study presents a modified control strategy based on PSO algorithm (CSPSO) for optimizing the power sharing between sources and reducing the components sizing. Furthermore, an interleaved multiple‐input power converter (IMIPC) is proposed for fuel cell hybrid electric vehicle to reduce the input current/output voltage ripples and to reduce the size of the passive components with high efficiency compared to conventional boost converter. Meanwhile, the fuel economy is improved. Moreover, a comparative study of FC/SC and FC/B HEVs will be provided to investigate the benefits of hybridization with energy storage system (ESS).
Integrates CAD/CAM, production control and process control in a case study involving manufacturing automation. The manufacturing firm is a distributed cellular system…
Integrates CAD/CAM, production control and process control in a case study involving manufacturing automation. The manufacturing firm is a distributed cellular system operating in a produce‐to‐order environment. Combines a parametric CAD software with global variables and global relations to achieve a design automation. Results obtained from design automation are transmitted to update the design model and the associative manufacturing model. In addition, scheduling and control are also integrated in the system. Distinguishes three scheduling levels: static scheduling, rescheduling, and real‐time scheduling. For a distributed and effective reason, the distributed shifting bottleneck procedure (DSBP) is adopted as the static scheduler and rescheduler, and the LRPT (longest bottleneck processing time) despatching rule is adopted as the real time despatching rule. FInally, introduces the configuration of the system including the flexible manufacturing cell architecture and the input buffer device. Uses a PLC programming toll that follows the IEC 1131‐3 standard to implement cell controllers. The above implementation aims to easily and effectively execute the CIM system.
Describes the development of an adaptive simulation model for a keyboard assembly cell for real‐time decision support. Discusses the architecture of the modelling and…
Describes the development of an adaptive simulation model for a keyboard assembly cell for real‐time decision support. Discusses the architecture of the modelling and control system, including the movement of entities and conveyors, describing how up to four different keyboard types may be modelled, with a PC cell controller continually monitoring the state changes of the assembly line, passing the data captured to the simulation model created in ARENA.
Considers the use of a computer based cell controller and monitor to meet cell design goals, with particular reference to the ITP cell controller. Describes in detail the modules of the cell controller: job control, schedule generation, schedule extinction, station manager, material handling manager, resource manager, access layer, and statistical process control. Surmises that by using standard modules, ITP can readily configure or reconfigure its cell controller.
Presents a proposal of computer integrated production planning and shopfloor control in a modular robot served flexible manufacturing cell. The manufacturing functions…
Presents a proposal of computer integrated production planning and shopfloor control in a modular robot served flexible manufacturing cell. The manufacturing functions involving scheduling, despatching and monitoring are integrated and mapped onto the multi‐level system architecture. Discusses functions of the system software modules, principles of communication between them and the technical requirements imposed on the system. Introduces simulation modelling tools based on the Petri net formalism to support the user in developing schedule solutions and estimating the overall manufacturing performance of the specific cell.