508 research outputs found
New Shop Floor Control Approaches for Virtual Enterprises
The virtual enterprise paradigm seems a fit response to face market instability and the volatile nature of business opportunities increasing enterprise’s interest in similar forms of networked organisations. The dynamic environment of a virtual enterprise requires that partners in the consortium own reconfigurable shop floors. This paper presents new approaches to shop floor control that meet the requirements of the new industrial paradigms and argues on work re-organization at shop floor level.virtual enterprise; networked organisations
Collaborative environment to support a professional community
Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para obtenção do grau de Mestre em Engenharia Electrotécnica e de ComputadoresRecent manufacturing roadmaps stress current production systems limitations, emphasizing social, economic and ecologic consequences for Europe of a non-evolution to sustainable Production Systems. Hence, both academic institutions and enterprises are committed to develop solutions that would endow enterprises to survive in nowadays’ extremely competitive business environment.
A research effort is being carried on by the Evolvable Production Systems consortium towards attaining Production Systems that can cope with current technological, economical, ecological and social demands fulfilling recent roadmaps. Nevertheless research success depends on attaining consensus in the scientific community and therefore an accurate critical mass support is required in the whole process.
The main goal of this thesis is the development of a Collaborative Environment Tool to assist Evolvable Production Systems consortium in such research efforts and to enhance Evolvable Assembly Systems paradigm dissemination. This work resulted in EASET (Evolvable Assembly Systems Environment Tool), a collaborative environment tool which promotes EAS dissemination and brings forth improvements through the raise of critical mass and collaboration between entities
New Shop Floor Control Approaches for Virtual Enterprises
The virtual enterprise paradigm seems a fit response to face market instability and the volatile nature of business opportunities increasing enterprise’s interest in similar forms of networked organisations.
The dynamic environment of a virtual enterprise requires that partners in the consortium own reconfigurable shop floors. This paper presents new approaches to shop floor control that meet the requirements of the new industrial paradigms and argues on work re-organization at shop floor level
Initial Validation of Robotic Operations for In-Space Assembly of a Large Solar Electric Propulsion Transport Vehicle
Developing a capability for the assembly of large space structures has the potential to increase the capabilities and performance of future space missions and spacecraft while reducing their cost. One such application is a megawatt-class solar electric propulsion (SEP) tug, representing a critical transportation ability for the NASA lunar, Mars, and solar system exploration missions. A series of robotic assembly experiments were recently completed at Langley Research Center (LaRC) that demonstrate most of the assembly steps for the SEP tug concept. The assembly experiments used a core set of robotic capabilities: long-reach manipulation and dexterous manipulation. This paper describes cross-cutting capabilities and technologies for in-space assembly (ISA), applies the ISA approach to a SEP tug, describes the design and development of two assembly demonstration concepts, and summarizes results of two sets of assembly experiments that validate the SEP tug assembly steps
A Quantitative Approach to Assessing System Evolvability
When selecting a system from multiple candidates, the customer seeks the one that best meets his or her needs. Recently the desire for evolvable systems has become more important and engineers are striving to develop systems that accommodate this need. In response to this search for evolvability, we present a historical perspective on evolvability, propose a refined definition of evolvability, and develop a quantitative method for measuring this property. We address this quantitative methodology from both a theoretical and practical perspective. This quantitative model is then applied to the problem of evolving a lunar mission to a Mars mission as a case study
The influence of the concept of capability-based management on the development of the systems engineering discipline
This paper explores the implications of a capability-based conceptual approach on the development of the systems engineering
(SE) discipline. It deals with the identification of some potential limits and gaps of traditional SE approaches and demonstrates
the need for new and innovative developments which support the concept of capability based engineering, especially as applied
in the military domain and networking environments. The innovative approaches include partnership for capability planning and
service descriptions for capability representations. The paper also presents a very brief assessment of the state-of-the-art of
cognate domains such as capability based planning alongside requirements engineering and management, and considers the
extent to which they address capability based concepts. The related concepts of system of systems (SoS) and the endeavour to
extend SE to SoS are necessarily addressed
Skill-based reconfiguration of industrial mobile robots
Caused by a rising mass customisation and the high variety of equipment versions, the
exibility of manufacturing systems in car productions has to be increased. In addition to
a
exible handling of production load changes or hardware breakdowns that are established
research areas in literature, this thesis presents a skill-based recon guration mechanism
for industrial mobile robots to enhance functional recon gurability.
The proposed holonic multi-agent system is able to react to functional process changes
while missing functionalities are created by self-organisation. Applied to a mobile commissioning
system that is provided by AUDI AG, the suggested mechanism is validated
in a real-world environment including the on-line veri cation of the recon gured robot
functionality in a Validity Check.
The present thesis includes an original contribution in three aspects: First, a recon -
guration mechanism is presented that reacts in a self-organised way to functional process
changes. The application layer of a hardware system converts a semantic description into
functional requirements for a new robot skill. The result of this mechanism is the on-line
integration of a new functionality into the running process.
Second, the proposed system allows maintaining the productivity of the running process
and
exibly changing the robot hardware through provision of a hardware-abstraction
layer. An encapsulated Recon guration Holon dynamically includes the actual con guration
each time a recon guration is started. This allows reacting to changed environment
settings. As the resulting agent that contains the new functionality, is identical in shape
and behaviour to the existing skills, its integration into the running process is conducted
without a considerable loss of productivity.
Third, the suggested mechanism is composed of a novel agent design that allows implementing
self-organisation during the encapsulated recon guration and dependability
for standard process executions. The selective assignment of behaviour-based and cognitive
agents is the basis for the
exibility and e ectiveness of the proposed recon guration
mechanism
Lightweight robust behavior industrial agent methodology
Dissertação para obtenção do Grau de Mestre em
Engenharia Electrotécnica e de ComputadoresAssembly systems today face significant pressure to provide highly adaptable and quickly deployable solutions in order to deal with unpredictable changes according to market trends. However, control of assembly processes are dominated by the use of Programmable Logical Controllers (PLC) which do not provide the necessary mechanisms to easily deal with these challenges. The concept of agent-based control has been introduced as a solution to deal these challenges and support new production paradigms based on the plug and produce concept. However, this solution has not yet been proven to be a real alternative to the traditional PLC approach in terms of performance. This work is investigating the use an approach that is able to benefit from the relative advantages of both PLC and agents solutions. A new hybrid architecture is presented which combines the functionalities of a PLC with those of industrial agents. The focus is on assessing the performance of this approach and help change the minds of an industry averse to changes
Service-oriented infrastructure to support the control, monitoring and management of a shop floor system
Dissertação para obtenção do Grau de Mestre em
Engenharia Electrotécnica e de ComputadoresService-oriented Architecture (SOA) paradigm is becoming a broadly deployed standard
for business and enterprise integration. It continuously spreads across the distinct
layers of the enterprise organization and disparate domains of application, envisioning
a unified communication solution. Service-oriented approaches are also entering the industrial automation domain in a top-down way. The recent application at device level
has a direct impact on how industrial automation deployments will evolve. Similarly
to other domains, the crescent ubiquity of smart devices is raising important lifecycle
concerns related to device control, monitoring and management. From initial setup and deployment to system lifecycle monitoring and evolution, each device needs to be taken into account and to be easily reachable.
The current work includes the specification and development of a modular, adaptive
and open infrastructure to support the control, monitoring and management of devices
and services in an industrial automation environment, such as a shop floor system. A
collection of tools and services to be comprised in this same infrastructure will also be researched and implemented. Moreover, the main implementation focuses on a SOA-based infrastructure comprising SemanticWeb concepts to enhance the process of exchanging a device in an industrial automation environment. This is done by assisting (and even automate)this task supported by service and device semantic matching whenever a device has a problem. The infrastructure was implemented and tested in an educational shop floor setup composed by a set of distributed entities each one controlled by its own SOAready
PLC. The performed tests revealed that the tasks of discovering and identifying
new devices, as well as providing assistance when a device is down offered a valuable
contribution and can increase the agility of the overall system when dealing with operation disruptions or modifications at device level
A Comparative Cost Analysis of Flexible and Evolvable Automatic Assembly Systems
The objective of this work was the formulation of a cost model able
to provide an evaluation of the economical effectiveness of an Evolvable
Production System (EPS) compared to the Flexible Manufacturing System
(FMS) within assembly process. Preliminary essential work was the
literature research on cost models, which confirmed the lack of economical
considerations about evolvable paradigm.
Two are the main contributions: the first is the definition of the cost model
for EPS and FMS throughout multiple product life cycles. After the definition
of the model, it has been proposed a parametrical comparative analysis
between the two systems within different productive scenarios. The comparative
cost analysis was simulated through the implementation of the model
on MATLAB.
This work takes place within the research about Evolvable Production
Systems carried out at KTH, the Royal Institute of Technology in Stockholm
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