269 research outputs found
Distribution of machine information using Blackboard designed component for remote monitoring of reconfigurable manufacturing systems
A blackboard-based design for a system component called the "Broadcaster" is described in this paper. It supports remote monitoring of reconfigurable manufacturing systems using a novel system architecture coupled with the Component-Based system paradigm. The design of this component has been evaluated using a case study on a web services-enabled test rig funded by the Ford Motor Company, U. K. The test rig has been implemented using a fully distributed control device called FTB, designed by the Schneider Electric Company. Evaluation of this component has been carried out using three scenario test cases which demonstrate the potentials offered when deploying this solution to a real production environment. The system component not only operates in a heterogeneous reconfigurable manufacturing environment, offering a vendor-independent solution to monitoring machines, but it also supports remote monitoring of the machines throughout their development and management lifecycles
Operator interfaces for the lifecycle support of component based automation systems
Current manufacturing automation systems (specifically the powertrain sector)
have been facing challenges with constant pressures of globalisation,
environmental concerns and ICT (Information and Communication Technology)
innovations. These challenges instigate new demands for shorter product
lifecycles and require customised products to be manufactured as efficiently as
possible. Manufacturing systems must therefore be agile to remain competitive
by supporting frequent reconfigurations involving distributed engineering
activities. [Continues.
A component-based approach to human–machine interface systems that support agile manufacturing
The development of next generation manufacturing systems is currently an active area of
research worldwide. Globalisation is placing new demands on the manufacturing industry
with products having shorter lifecycles and being required in more variants. Manufacturing systems must therefore be agile to support frequent manufacturing system reconfiguration
involving globally distributed engineering partners. The research described in this thesis
addresses one aspect within this research area, the Human Machine Interface (HMI) system
that support the personnel involved in the monitoring, diagnostics and reconfiguration of
automated manufacturing production machinery.
Current HMI systems are monolithic in their design, generally offer poor connectivity to
other manufacturing systems and require highly skilled personnel to develop and maintain
them.
The new approach established in the research and presented in this thesis provides a
specification capture technique (using a novel storyboarding modelling notation) that enables
the end users HMI functionality to be specified and rapidly developed into fully functional
End User HMI's via automated generation tools.
A novel feature in this HMI system architecture that all machine information is stored in a common unified machine data model which ensures consistent accurate machine data is
available to all machine lifecycle engineering tools including the HMI.
The system's run-time architecture enables remote monitoring and diagnostics capabilities to
be available to geographically distributed engineering partners using standard internet technologies. The implementation of this novel HMI approach has been prototyped and evaluated using the industrial collaborators full scale demonstrator machines within cylinder head machining and engine assembly applications
Development of a toolkit for component-based automation systems
From the earliest days of mass production in the automotive industry there has been a
progressive move towards the use of flexible manufacturing systems that cater for
product variants that meet market demands. In recent years this market has become
more demanding with pressures from legislation, globalisation and increased
customer expectations. This has lead to the current trends of mass customisation in
production.
In order to support this manufacturing systems are not only becoming more flexibleâ€
to cope with the increased product variants, but also more agile‡ such that they may
respond more rapidly to market changes. Modularisation§ is widely used to increase
the agility of automation systems, such that they may be more readily reconfigured¶.
Also with globalisation into India and Asia semi-automatic machines (machines that
interact with human operators) are more frequently used to reduce capital outlay and
increase flexibility. There is an increasing need for tools and methodologies that
support this in order to improve design robustness, reduce design time and gain a
competitive edge in the market.
The research presented in this thesis is built upon the work from
COMPAG/COMPANION (COMponent- based Paradigm for AGile automation, and
COmmon Model for PArtNers in automatION), and as part of the BDA (Business
Driven Automation), SOCRADES (Service Oriented Cross-layer infrastructure for
Distributed smart Embedded deviceS), and IMC-AESOP (ArchitecturE for Service-
Oriented Process – monitoring and control) projects conducted at Loughborough
University UK.
This research details the design and implementation of a toolkit for building and
simulating automation systems comprising components with behaviour described
using Finite State Machines (FSM). The research focus is the development of the
engineering toolkit that can support the automation system lifecycle from initial
design through commissioning to maintenance and reconfiguration as well as the
integration of a virtual human. This is achieved using a novel data structure that
supports component definitions for control, simulation, maintenance and the novel
integration of a virtual human into the automation system operation
Web service control of component-based agile manufacturing systems
Current global business competition has resulted in significant challenges for
manufacturing and production sectors focused on shorter product lifecyc1es, more diverse
and customized products as well as cost pressures from competitors and customers. To
remain competitive, manufacturers, particularly in automotive industry, require the next
generation of manufacturing paradigms supporting flexible and reconfigurable production
systems that allow quick system changeovers for various types of products. In addition,
closer integration of shop floor and business systems is required as indicated by the
research efforts in investigating "Agile and Collaborative Manufacturing Systems" in
supporting the production unit throughout the manufacturing lifecycles.
The integration of a business enterprise with its shop-floor and lifecycle supply partners
is currently only achieved through complex proprietary solutions due to differences in
technology, particularly between automation and business systems. The situation is
further complicated by the diverse types of automation control devices employed.
Recently, the emerging technology of Service Oriented Architecture's (SOA's) and Web
Services (WS) has been demonstrated and proved successful in linking business
applications. The adoption of this Web Services approach at the automation level, that
would enable a seamless integration of business enterprise and a shop-floor system, is an
active research topic within the automotive domain. If successful, reconfigurable
automation systems formed by a network of collaborative autonomous and open control
platform in distributed, loosely coupled manufacturing environment can be realized
through a unifying platform of WS interfaces for devices communication.
The adoption of SOA- Web Services on embedded automation devices can be achieved
employing Device Profile for Web Services (DPWS) protocols which encapsulate device
control functionality as provided services (e.g. device I/O operation, device state
notification, device discovery) and business application interfaces into physical control
components of machining automation. This novel approach supports the possibility of
integrating pervasive enterprise applications through unifying Web Services interfaces
and neutral Simple Object Access Protocol (SOAP) message communication between
control systems and business applications over standard Ethernet-Local Area Networks
(LAN's). In addition, the re-configurability of the automation system is enhanced via the
utilisation of Web Services throughout an automated control, build, installation, test,
maintenance and reuse system lifecycle via device self-discovery provided by the DPWS
protocol...cont'd
An agent based layered framework to facilitate intelligent Wireless Sensor Networks
Includes bibliographical references (leaves 78-80).Wireless Sensor Networks (WSNs) are networks of small, typically low-cost hardware devices which are able to sense various physical phenomenon in their surrounding environments. These simple nodes are also able to perform basic processing and wirelessly communicate with each other. The power of these networks arise from their ability to combine their many vantage points of the individual nodes and to work together. This allows for behaviour to emerge which is greater than the sum of the ability of all the nodes in the network. The complexity of these networks varies based on the application domain and the physical phenomenon being sensed. Although sensor networks are currently well understood and used in a number of real world applications, a number limitations still exit. This research aims to overcome a number of issues faced by current WSNs, the largest of which is their monolithic or tightly coupled structure which result in static and application specific WSNs. We aim to overcome these issues by designing a dynamically reconfigurable system which is application neutral. The proposed system is also required to facilitate intelligence and be sufficiently efficient for low power sensor node hardware
Diagnosis of an EPS module
Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova
de Lisboa para obtenção do grau de Mestre em Engenharia Electrotécnica e ComputadoresThis thesis addresses and contextualizes the problem of diagnostic of an Evolvable
Production System (EPS). An EPS is a complex and lively entity composed of intelligent modules that interact through bio-inspired mechanisms, to ensure high system availability and seamless reconfiguration.
The actual economic situation together with the increasing demand of high quality and low
priced customized products imposed a shift in the production policies of enterprises. Shop floors have to become more agile and flexible to accommodate the new production paradigms. Rather than selling products enterprises are establishing a trend of offering services to explore business
opportunities.
The new production paradigms, potentiated by the advances in Information Technologies
(IT), especially in web related standards and technologies as well as the progressive acceptance of the multi-agent systems (MAS) concept and related technologies, envision collections of modules whose individual and collective function adapts and evolves ensuring the fitness and adequacy of the shop
floor in tackling profitable but volatile business opportunities. Despite the richness of the interactions and the effort set in modelling them, their potential to favour fault propagation and interference, in
these complex environments, has been ignored from a diagnostic point of view.
With the increase of distributed and autonomous components that interact in the execution of processes current diagnostic approaches will soon be insufficient. While current system dynamics are complex and to a certain extent unpredictable the adoption of the next generation of approaches and technologies comes at the cost of a yet increased complexity.Whereas most of the research in such distributed industrial systems is focused in the study and establishment of control structures, the problem of diagnosis has been left relatively unattended.
There are however significant open challenges in the diagnosis of such modular systems including:
understanding fault propagation and ensuring scalability and co-evolution.
This work provides an implementation of a state-of-the-art agent-based interaction-oriented architecture compliant with the EPS paradigm that supports the introduction of a new developed diagnostic algorithm that has the ability to cope with the modern manufacturing paradigm challenges and to provide diagnostic analysis that explores the network dimension of multi-agent systems
Advancing automation and robotics technology for the space station and for the US economy: Submitted to the United States Congress October 1, 1987
In April 1985, as required by Public Law 98-371, the NASA Advanced Technology Advisory Committee (ATAC) reported to Congress the results of its studies on advanced automation and robotics technology for use on the space station. This material was documented in the initial report (NASA Technical Memorandum 87566). A further requirement of the Law was that ATAC follow NASA's progress in this area and report to Congress semiannually. This report is the fifth in a series of progress updates and covers the period between 16 May 1987 and 30 September 1987. NASA has accepted the basic recommendations of ATAC for its space station efforts. ATAC and NASA agree that the mandate of Congress is that an advanced automation and robotics technology be built to support an evolutionary space station program and serve as a highly visible stimulator affecting the long-term U.S. economy
Self-organisation of mobile robots in large structure assembly using multi-agent systems
Competition between manufacturers in large structure assembly (LSA) is driven by the need to improve the adaptability and versatility of their manufacturing systems. The lack of these qualities in the currently used systems is caused by the dedicated nature of their fixtures and jigs. This has led to their underutilisation and costly changeover procedures. In addition to that, modern automation systems tend to be dedicated to very specific tasks. This means that such systems are highly specialised and can reach obsolescence once there is a substantial change in production requirements. In this doctoral thesis, a dynamic system consisting of mobile robots is proposed to overcome those limitations.
As a first knowledge contribution in this doctoral thesis, it is investigated under which conditions using mobile robots instead of the traditional, fixed automation systems in LSA can be advantageous. In this context, dynamic systems are expected to be more versatile and adaptive than fixed systems. Unlike traditional, dedicated automation systems, they are not constrained to gantry rails or fixed to the floor. This results in an expanded working envelope and consequently the ability to reach more workstations. Furthermore, if a product is large enough, the manufacturer can choose how many mobile robots to deploy around it. Accordingly, it was shown that the ability to balance work rates on products and consequently meet their due times is improved.
For the second knowledge contribution, two fundamentally different decision-making models for controlling mobile agents in the complex scheduling problem are investigated. This is done to investigate ways of taking full advantage from the potential benefits of applying mobile robots. It is found that existing models from related academic literature are not suited for the given problem. Therefore, two new models had to be proposed for this purpose. It was plausible to use an agent-based approach for self-organisation. This is because similarly to agents, mobile robots can perform independently of one-another; and have limited perception and communication abilities.
Finally, through a comparison study, scenarios are identified where either model is better to use. In agreement with much of the established literature in the field, the models are shown to exhibit the common advantages and disadvantages of their respective architecture types.
Considering that the enabling technologies are nearing sufficient maturity for deploying mobile robots in LSA, it is concluded that this approach can have several advantages. Firstly, the granularity and freedom of movement enables much more control over product completion times. Secondly, the increased working envelope enables higher utilisation of manufacturing resources. In the context of LSA, this is a considerable challenge because products take a very long time to get loaded and unloaded from workstations. However, if the product flow is steady, there are rare disruptions and rare production changes, fixed automation systems have an advantage due to requiring much less time (if any) for moving and localising. Therefore, mobile systems become more preferred to fixed systems in environments where there is an increasing frequency of disruptions and changes in production requirements.
The validation of agent-based self-organisation models for mobile robots in LSA confirms the expectations based on existing literature. Also, it reveals that with relatively low amounts of spare capacity (5%) in the manufacturing systems, there is little need for sophisticated models. The value of optimised models becomes apparent when spare capacity approaches 0% (or even negative values) and there is less room for inefficiencies in scheduling
Design and implementation of a modular controller for robotic machines
This research focused on the design and implementation of an Intelligent Modular Controller (IMC) architecture designed to be reconfigurable over a robust network. The design incorporates novel communication, hardware, and software architectures. This was motivated by current industrial needs for distributed control systems due to growing demand for less complexity, more processing power, flexibility, and greater fault tolerance. To this end, three main contributions were made. Most distributed control architectures depend on multi-tier heterogeneous communication networks requiring linking devices and/or complex middleware. In this study, first, a communication architecture was proposed and implemented with a homogenous network employing the ubiquitous Ethernet for both real-time and non real-time communication. This was achieved by a producer-consumer coordination model for real-time data communication over a segmented network, and a client-server model for point-to-point transactions. The protocols deployed use a Time-Triggered (TT) approach to schedule real-time tasks on the network. Unlike other TT approaches, the scheduling mechanism does not need to be configured explicitly when controller nodes are added or removed. An implicit clock synchronization technique was also developed to complement the architecture. Second, a reconfigurable mechanism based on an auto-configuration protocol was developed. Modules on the network use this protocol to automatically detect themselves, establish communication, and negotiate for a desired configuration. Third, the research demonstrated hardware/software co-design as a contribution to the growing discipline of mechatronics. The IMC consists of a motion controller board designed and prototyped in-house, and a Java microcontroller. An IMC is mapped to each machine/robot axis, and an additional IMC can be configured to serve as a real-time coordinator. The entire architecture was implemented in Java, thus reinforcing uniformity, simplicity, modularity, and openness. Evaluation results showed the potential of the flexible controller to meet medium to high performance machining requirements
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