| 1. |
- Alzghoul, Ahmad, et al.
(författare)
-
Data stream mining for increased functional product availability awareness
- 2011
-
Ingår i: Functional Thinking for Value Creation. - Berlin, Heidelberg : Springer Berlin/Heidelberg. - 9783642196881 - 9783642196898 ; , s. 237-241
-
Konferensbidrag (refereegranskat)abstract
- Functional Products (FP) and Product Service Systems (PSS) may be seen as integrated systems comprising hardware and support services. For such offerings, availability is key. Little research has been done on integrating Data Stream Management Systems (DSMS) for monitoring (parts of) a FP to improve system availability. This paper introduces an approach for how data stream mining may be applied to monitor hardware being part of a Functional Product. The result shows that DSMS have the potential to significantly support continuous availability awareness of industrial systems, especially important when the supplier is to supply a function with certain availability.
|
|
| 2. |
- Karlsson, Lennart, et al.
(författare)
-
Editorial
- 2013
-
Ingår i: International Journal of Product Development. - Bucks, United Kingdom : InderScience Publishers. - 1477-9056 .- 1741-8178. ; 18:1, s. 1-2
-
Tidskriftsartikel (refereegranskat)
|
|
| 3. |
- Lindström, John, et al.
(författare)
-
A development process for Functional Products : hardware, software, service support system and management of operation
- 2012
-
Ingår i: International Journal of Product Development. - : InderScience Publishers. - 1477-9056 .- 1741-8178. ; 16:3/4, s. 284-303
-
Tidskriftsartikel (refereegranskat)abstract
- The development process for a Functional Product (FP) is complex and there is a need to coordinate, monitor, control and share information as well as to communicate properly among the parties involved in the process. This paper proposes a conceptual development process to manage the FP development, including development of hardware, software, service support system, and how to manage the operation of an FP. Further, challenges related to the integrated development of FPs are also discussed.
|
|
| 4. |
- Löfstrand, Magnus, 1974-, et al.
(författare)
-
Functional product system availability : simulation-driven design and operation through coupled multi-objective optimisation
- 2011
-
Ingår i: International Journal of Product Development. - Bucks, United Kingdom : InderScience Publishers. - 1477-9056 .- 1741-8178. ; 13:2, s. 119-131
-
Tidskriftsartikel (refereegranskat)abstract
- This paper describes on a conceptual level how the availability of functional products (consisting of hardware (HW) and a support system) may be simulated. The main objective of this paper is to present a simulation-driven methodology for predicting and optimising the availability and cost of functional products in both development and operation. The proposed simulation and optimisation methodology includes both HW and support system models, which coupled form a simulation model of a system (functional product) delivering the function. Two different simulation-driven methodologies are suggested in the paper: one for development and another for operation of functional products
|
|
| 5. |
- Löfstrand, Magnus, 1974-, et al.
(författare)
-
Modelling and simulation of functional product system availability and support costs
- 2012
-
Ingår i: International Journal of Product Development. - Bucks, United Kingdom : InderScience Publishers. - 1477-9056 .- 1741-8178. ; 16:3-4, s. 304-325
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Functional products (FP), total offers or product service systems, that comprise of both hardware (HW) and support services (SS) sold as an integrated offering under an availability guarantee, are becoming increasing popular in industry. This paper addresses, through modelling and simulation, the challenge faced by suppliers in developing an integrated HW and SS design to produce an FP which meets contracted availability. A recently published framework specified how an integrated model hardware and service support system model could be used to obtain functional availability predictions and perform simulation driven functional product development. This paper presents the first example of an integrated functional product model. It uses fault tree, Petri net and discrete event simulation techniques to enable the prediction of functional product availability and support costs. Such predictions are used here to evaluate and compare different service support system designs.
|
|
| 6. |
- Reed, Sean, et al.
(författare)
-
Modelling service support system reliability
- 2010
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Functional Products, where the customer pays for the function and availability of a product instead of the product itself, are increasingly popular in capital intensive industries such as aerospace. Such products are integrated systems involving the combination of hardware and service support systems. The reliability prediction and optimisation of the service system that supports the hardware availability is essential to the feasibility of the product. These systems consist of maintenance procedures and resource provisions. Simulation based techniques are presented in this paper to analyse the reliability of support systems and their application is demonstrated through a simple example.
|
|
| 7. |
- Alzghoul, Ahmad, et al.
(författare)
-
Addressing concept drift to improve system availability by updating one-class data-driven models
- 2015
-
Ingår i: Evolving Systems. - : Springer. - 1868-6478 .- 1868-6486. ; 6:3, s. 187-198
-
Tidskriftsartikel (refereegranskat)abstract
- Data-driven models have been used to detect system faults, thereby increasing industrial system availability. The ability to search data streams while dealing with concept drift are challenges for data-driven models. The objective of this work is to demonstrate a general method to manage concept drift when using one-class data-driven models. The method has been used to develop an automatically retrained and updated polygon-based model. In this paper, the available industrial data allowed for use of one-class data-driven models, and the polygon-based model was selected because it has previously been successful. Possible scenarios that allow one-class data-driven models to be retrained or updated were identified. Based on the identified scenarios, a method to automatically update a polygon-based model online is proposed. The method has been tested and verified using data collected from a Bosch Rexroth Mellansel AB hydraulic drive system. Data representing relevant faults was inserted into the data set in close collaboration with engineers from the company. The results show that the developed polygon-based model method was able to address the concept drift issue and was able to significantly improve the classification accuracy compared to the static polygon-based model. Thereby, the model could significantly improve industrial system availability when applied in the relevant production process. This paper shows that the developed polygon-based model requires small memory space while its updating procedure is simple and fast. Finally, the identified scenarios may be helpful as input for supporting other one-class data-driven models to cope with concept drift, thus increasing the generalizability of the results.
|
|
| 8. |
- Alzghoul, Ahmad, et al.
(författare)
-
Data stream forecasting for system fault prediction
- 2012
-
Ingår i: Computers & industrial engineering. - : Elsevier. - 0360-8352 .- 1879-0550. ; 62:4, s. 972-978
-
Tidskriftsartikel (refereegranskat)abstract
- Competition among today’s industrial companies is very high. Therefore, system availability plays an important role and is a critical point for most companies. Detecting failures at an early stage or foreseeing them before they occur is crucial for machinery availability. Data analysis is the most common method for machine health condition monitoring. In this paper we propose a fault-detection system based on data stream prediction, data stream mining, and data stream management system (DSMS). Companies that are able to predict and avoid the occurrence of failures have an advantage over their competitors. The literature has shown that data prediction can also reduce the consumption of communication resources in distributed data stream processing. In this paper different data-stream-based linear regression prediction methods have been tested and compared within a newly developed fault detection system. Based on the fault detection system, three DSM algorithms outputs are compared to each other and to real data. The three applied and evaluated data stream mining algorithms were: Grid-based classifier, polygon-based method, and one-class support vector machines (OCSVM). The results showed that the linear regression method generally achieved good performance in predicting short-term data. (The best achieved performance was with a Mean Absolute Error (MAE) around 0.4, representing prediction accuracy of 87.5%). Not surprisingly, results showed that the classification accuracy was reduced when using the predicted data. However, the fault-detection system was able to attain an acceptable performance of around 89% classification accuracy when using predicted data.
|
|
| 9. |
- Alzghoul, Ahmad, et al.
(författare)
-
Increasing availability of industrial systems through data stream mining
- 2011
-
Ingår i: Computers & industrial engineering. - : Elsevier. - 0360-8352 .- 1879-0550. ; 60:2, s. 195-205
-
Tidskriftsartikel (refereegranskat)abstract
- Improving industrial product reliability, maintainability and thus availability is a challenging task for many industrial companies. In industry, there is a growing need to process data in real time, since the generated data volume exceeds the available storage capacity. This paper consists of a review of data stream mining and data stream management systems aimed at improving product availability. Further, a newly developed and validated grid-based classifier method is presented and compared to one-class support vector machine (OCSVM) and a polygon-based classifier.The results showed that, using 10% of the total data set to train the algorithm, all three methods achieved good (>95% correct) overall classification accuracy. In addition, all three methods can be applied on both offline and online data.The speed of the resultant function from the OCSVM method was, not surprisingly, higher than the other two methods, but in industrial applications the OCSVMs' comparatively long time needed for training is a possible challenge. The main advantage of the grid-based classification method is that it allows for calculation of the probability (%) that a data point belongs to a specific class, and the method can be easily modified to be incremental.The high classification accuracy can be utilized to detect the failures at an early stage, thereby increasing the reliability and thus the availability of the product (since availability is a function of maintainability and reliability). In addition, the consequences of equipment failures in terms of time and cost can be mitigated.
|
|
| 10. |
- Eklund, Patrik, et al.
(författare)
-
Many-valued and many-sorted structure relations
- 2019
-
Ingår i: DS 97. - München : The Design Society. - 9781912254064 ; , s. 141-150
-
Konferensbidrag (refereegranskat)abstract
- System-of-systems engineering and related models of engineering design require intertwining of structures, respectively, at least for components in products, engineering and business activities, and people involved in those activities as also specifically connected with production and its management. In this paper we describe the logical machinery of system-of-systems engineering and related models of engineering design in sufficient so as to enable to describe the algebraic foundation of the many-valued logic that is inherent in these systems and structures. We are thus essentially unravelling the hidden and underlying logic of these systems and their related information and process structures, focusing on interaction between elements of the system.
|
|
| 11. |
- Eklund, Patrik, et al.
(författare)
-
Many-valued logic in manufacturing
- 2016
-
Ingår i: 11th International Symposium Advances in Artificial Intelligence and Applications.
-
Konferensbidrag (refereegranskat)
|
|
| 12. |
- Eklund, Patrik, et al.
(författare)
-
Uncertainty of value and structure
- 2019
-
Ingår i: Proceedings of the 11th Conference of the European Society for Fuzzy Logic and Technology (EUSFLAT 2019). - Paris, France : Atlantis Press. - 9789462527706 ; , s. 370-375
-
Konferensbidrag (refereegranskat)abstract
- In this paper we argue that `uncertainty of information' traditionally focuses more on `uncertainty' leaving `information' mostly as unravelled. We also aim to explain why that is so, and we then provide suggestions on how to overcome the situation, as related to applications involving information structures.
|
|
| 13. |
- Johanson, Mathias, et al.
(författare)
-
Collaborative innovation through distributed engineering services
- 2009
-
Ingår i: Proceedings of International Multi-Conference on Engineering and Technological Innovation.
-
Konferensbidrag (refereegranskat)abstract
- Rapid advancement in information and communication technology in recent decades has presented new opportunities for carrying out sophisticated engineering work in distributed teams, using tools and techniques collectively referred to as Distributed Collaborative Engineering (DCE). This kind of on-line collaboration not only cuts costs due to reduced travel, but also fosters innovation in product development, by bringing together groups of people in collaborative teams with complementary competences, that would otherwise be difficult to realize. Moreover, the convergence of technologies for telecommunication and information technology now makes it possible for companies specialized in collaboration technology to deliver sophisticated services for DCE, which can be purchased by engineering companies on a pay-per-use basis. By outsourcing the installation, management and support of the collaboration tools, the engineering companies can focus on their product development projects while harnessing the full potential of DCE to become more efficient and competitive. We believe that this new way of conducting engineering work will be an important key to innovation in the future. In this paper, we analyze the requirements for delivering DCE as a service and describe the implications this has in terms of systems design, business models and competence requirements. Furthermore, in addition to the primary return on investment in DCE services, we cite cost reductions and reduced CO2 emissions as further benefits.
|
|
| 14. |
- Karlsson, Lennart, et al.
(författare)
-
Information driven collaborative engineering : enabling functional product innovation
- 2005
-
Ingår i: Challenges in Collaborative Engineering - CCE '05. - Jönköping, Sweden : Department of Computer & Electrical Engineering, School of Engineering, Jönköping University. - 9197560413
-
Konferensbidrag (refereegranskat)abstract
- This paper discusses Information Driven Collaborative Engineering (IDCE) as an enabler of Functional Product Innovation (FPI). It discusses challenges that arise in functional product development and how distributed collaborative work will be affected. Finally the paper proposes bringing the domains of Distributed Collaborative Engineering (DCE) and Knowledge Enabled Engineering (KEE) together to form IDCE, in order to meet these challenges.
|
|
| 15. |
- Kyösti, Petter, et al.
(författare)
-
Simulation of industrial support systems in the context of functional products
- 2011
-
Ingår i: Proceedings of the 19th AR2TS Advances in Risk and Reliability Technology Symposium. - Nottingham : University of Nottingham. ; , s. 275-288
-
Konferensbidrag (refereegranskat)abstract
- Functional Products, consisting of hardware and service support systems owned by the supplier, are sold to customers with a guaranteed availability of the function. The availability achieved is dependent on the reliability of both hardware and the service support system. The reliability of the latter can be defined as its ability to provide the required maintenance services in a timely manner. This paper reports simulation of a service support system from an industrial case study in order to predict its reliability. To identify and develop a suitable case together with an industrial partner company, a number of phone meetings were held in order to explain the research question, interview knowledgeable people and plan on-site visits and interviews. A number of interviews face to face were carried out with the industrial partners, where the goal was to obtain enough information to be able to model the support system correctly. The research involved both qualitative information gathering and applied computer aided simulation. An improved model for simulating a service support system is developed that considers the context in which the maintenance procedures are performed within a Functional Product. A software implementation of the model, developed by the authors, is applied to simulate the case study service support system in various scenarios such as different personnel availability and number of systems supported. The results show how the modeling can be used to improve and predict the reliability of the service support system
|
|
| 16. |
- Larsson, Andreas, et al.
(författare)
-
Design for versatility : the changing face of workspaces for collaborative design
- 2005
-
Ingår i: Proceedings ICED 05, the 15th International Conference on Engineering Design. - Melbourne : The Institution of Engineers, Australia. - 9780858257887
-
Konferensbidrag (refereegranskat)abstract
- In a fiercely competitive business climate, which is increasingly characterized by global alliances, partnerships and outsourcing agreements, companies struggle to decrease the negative impact of geographic distance on development efforts. The role of workspaces for collaborative design is gaining considerable attention, and there is currently an increasing interest in moving from individual tools or technologies to a more inclusive view of collaborative workspaces. This paper reports on the underlying motivation and justification for a new collaborative design studio at Luleå University of Technology, Sweden. The studio provides a rapid-response environment, in which the significance of issues raised through ethnographic observations of engineering work can be evaluated and solutions offered.
|
|
| 17. |
- Larsson, Daniel, et al.
(författare)
-
Computer visualisations in design for maintainability
- 2000
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The main goal of research at the Polhem Laboratory is to develop technologies for product development and manufacturing through integration of design, development, manufacturing, materials engineering and maintenance in Swedish industry. Concurrent engineering, which is a central theme of this research, is instrumental for developing products with shorter lead times at lower cost and for adapting products for manufacturing and maintenance. One purpose of the work presented was to show its applications in the field of Design For Maintainability where computer visualisations might improve the early design process. Another purpose of this work was to use modern information technology, and especially computer graphics, to develop a method to visualize the disassembly / assembly of a mechanical product. An important feature of this work was that 'visualizations,' rather then plain animations, were to be developed; the difference being that visualizations includes information about tools, times and explanations aswell as images of the moving parts. Integrating the use of conventional CAD-programmes with the use of animation programmes also makes it easier to use older models in new projects and thereby shortening lead times.
|
|
| 18. |
- Lindström, John, et al.
(författare)
-
A function innovation model for the manufacturing industry
- 2016
-
Ingår i: Journal of Multi Business Model Innovation and Technology. - : River Publishers. - 2245-8832 .- 2245-456X. ; 3:1, s. 1-28
-
Tidskriftsartikel (refereegranskat)abstract
- The paper addresses the need for innovation in order to achieve sustainable growth and business development within the manufacturing industry, and further how that can be enabled by striving towards functions. Adopting an open perspective, the paper proposes a function innovation model involving academia, potential function providers and customers in order to create a long-term win-win situation between function providers and their customers.
|
|
| 19. |
- Lindström, John, et al.
(författare)
-
Functional product development : criteria for selection of design methods on strategic and operational levels
- 2013
-
Ingår i: The Philosopher's Stone for Sustainability. - Berlin, Heidelberg : Springer. - 9783642328466 - 9783642328473 ; , s. 25-30
-
Konferensbidrag (refereegranskat)abstract
- The paper proposes criteria that can be used for selection of design methods on strategic and operational levels in Functional Product development. The paper draws on research from general product development and specific research within Product-Service Systems and Functional Products, combined with empirical data from interviews with four organizations concerned with Functional Product development. The use of many design methods requires resources such as knowledge and skills, which may not always be feasible to keep in-house. However, the key design methods needed in-house should be identified, added to the set of approved design methods and granted adequate resource allocation.
|
|
| 20. |
- Lindström, John, et al.
(författare)
-
Use of cloud services in functional products : availability implications
- 2014
-
Ingår i: Product Services Systems and Value Creation. - : Elsevier. ; 16, s. 368-372
-
Konferensbidrag (refereegranskat)abstract
- The paper addresses the potential use of cloud services in Functional Products (FP) and its possible implications for availability. Further, how the implications for availability can be understood via modelling and simulation is addressed. The paper adds further specificity to literature by indicating the FP constituents for which cloud services are applicable and adequate.
|
|
| 21. |
- Löfstrand, Magnus, 1974-, et al.
(författare)
-
A process modelling and simulation approach for business decision support in pre-conceptual product design
- 2010
-
Ingår i: International Journal of Product Development. - Bucks, United Kingdom : InderScience Publishers. - 1477-9056 .- 1741-8178. ; 12:2, s. 158-175
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- This paper discusses creation of a support tool (SIMULINK model) for collaborative work process modelling and optimisation based on Simulation Driven Design (SDD). The purpose is to improve the studied company's ability to develop hardware-based services in an early concept stage, and to predict performance of a given service scenario before development. The approach is useful as a decision-support tool in evaluating and prioritising business offers and activities in the business offer process. The modelling and simulation approach minimises the cost of each concept and allows simulation of a number of different concepts before the actual work is carried out
|
|
| 22. |
- Löfstrand, Magnus, 1974-, et al.
(författare)
-
An activity based simulation approach to functional product development
- 2006
-
Ingår i: Challenges in collaborative engineering: CCE '06. - Jönköping, Sweden : Department of Computer & Electrical Engineering, School of Engineering, Jönköping University. - 919756043X ; , s. 107-118
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- This paper discusses the new demands that are placed on tools and methods used in industrial product development due to the transformation of industrial companies from hardware producers to function providers, including some effects on collaborative engineering. Traditionally, manufacturing industry focuses on providing excellent goods, i.e. hardware. Services occur on an aftermarket, as an add-on to the developed hardware. By supplying functions, companies can gain control of the aftermarket. The responsibility and availability of the functions provided by hardware remains with the function provider as well as the responsibility for maintenance and spare parts. This approach, a new business mode, is a response to a necessity for business-to-business collaboration to gain economy––of-scale partnerships in the extended enterprise and ultimately to be able to develop competitive offers [1] [2]. Hence, the shift in view is a move towards providing functions, taking a lifecycle commitment for the hardware as well as optimizing the availability of its function in the customers’’ system. The redirection from hardware development to a process where development of functions is in focus is hereafter referred to as Functional Product Development.
|
|
| 23. |
- Löfstrand, Magnus, 1974-, et al.
(författare)
-
Demands on engineering design culture for implementing functional products
- 2005
-
Ingår i: Proceedings ICED 05, the 15th International Conference on Engineering Design, Melbourne, Australia, 15.-18.08.2005. - Glasgow, United Kingdom : The Design Society. - 0858257882 ; , s. 172-173
-
Konferensbidrag (refereegranskat)abstract
- Industrial product development focused companies, such as car manufacturers, have traditionally developed and sold hardware products. In professional business-to-business relations, the integration of hardware and software with services has been identified as a shift in focus in the seller-buyer relationship from hardware development to function development and the way a sustainable economic performance could be achieved. Therefore, the common perception today of where the product is mainly hardware only, needs to be expanded to include a definition where it does not even have to have any hardware at all. Expanding the product definition therefore places additional demands on the design and development of hardware, software and services that may all be part of the functional product. Further, this article discusses how customer requirements need to be handled when developing a total offer in the form of a functional product. Finally, the traits needed in the engineer who is to develop it while being part of amulti-cultural team are discussed, possibly a geographically distributed team.
|
|
| 24. |
- Löfstrand, Magnus, 1974-, et al.
(författare)
-
Evaluating availability of functional products through simulation
- 2014
-
Ingår i: Simulation Modelling Practice and Theory. - Amsterdam, Netherlands : Elsevier. - 1569-190X .- 1878-1462. ; 47, s. 196-209
-
Tidskriftsartikel (refereegranskat)abstract
- A functional product is an integrated package consisting of hardware, software and a service support system that provides a customer with a certain function and is sold under a performance-based contract that includes a functional availability guarantee. For the availability performance, prediction, optimisation and management of risk are therefore important concerns during product development. This paper describes a software tool that can generate an integrated model of a functional product from its design details and analyse it through simulation to provide availability performance information. The model's application to the analysis of a real industrial system is demonstrated. Such tools are important for the development and widespread adoption of functional products. The resulting analysis gave an indication of a suitable guaranteed functional availability level for the product and could be used to compare the performance of different design options.
|
|
| 25. |
- Löfstrand, Magnus, 1974-
(författare)
-
Hardware design as a basis for functional product development
- 2004
-
Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The business environment in manufacturing industry is changing from a hardware based product focus to a process and function focus. A current industrial interest is the development and sale of functions. This function could be realised as a product based on hardware, software and services and may be sold as a function rather than as hardware. This function view is referred to as Functional Products (FP). The new focus is on value for the customer rather than on hardware for the customer. This change creates new challenges for how engineering design of the hardware may best be carried out. To develop a functional product, several parties need to be involved in the particular project. These parties are suggested to be supplier, seller, sub- contractor, customer and end user. Since the functional product is not only consisting of hardware but also of services the relations between manufacturers and customers will change. Product development will be carried out in networks to an increasing degree where assignments, activities of, and relations between involved parties will be continuously changing. This thesis introduces the area of functional products and related literature from a hardware engineering design perspective. It starts from a holistic approach and introduce the area of functional products in relation to traditional hardware design and development. Product and process issues considered to be important are raised and discussed; value of hardware product versus value of functions, increased need for integration, communication and collaboration over cross-disciplinary borders, increased need for simulation support to be able to increase the predictability of design concepts. Simulation as an activity to verify the capabilities of the hardware product must be taken for granted in functional product business negotiation. Elongated needs exploration and identification stage are likely early on in functional product development. The concept verification stage in product development of functional products is suggested to increase until such times when integrated simulation support has been developed to support system simulation of functional products. Additionally, issues brought forward in this thesis include: -Suggestions on processes necessary for functional product development -Changes in value for the customer and ownership of the hardware with the introduction of the FP concept - Questions have been raised for how the engineering design activities actually will be affected with the introduction of functional products The thesis is seen as exploratory rather than verifying and invites discussion of the issues raised here, in order for these issues to be developed further.
|
|
| 26. |
- Löfstrand, Magnus, 1974-
(författare)
-
Linking design process activities to the business decisions of the firm : an example from the aerospace industry
- 2010
-
Ingår i: International Journal of Product Development. - Bucks, United Kingdom : InderScience Publishers. - 1477-9056 .- 1741-8178. ; 12:2, s. 141-157
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- The research concerns identification of parameters important for the studied organisation's success in service concept design and delivery. Knowledge was gathered through interviews and participation in daily industrial work activities. The gathered knowledge was used for developing a MATLAB-based simulation model, of which the purpose is to improve the studied company's ability to develop hardware-based services at an early concept stage, and to simulate, beforehand, the predicted performance of a given service scenario. This approach minimises the cost of each concept and allows simulation of several different concepts before the actual work is done.
|
|
| 27. |
- Paul, Satyam, et al.
(författare)
-
A Vibration Based Automatic Fault Detection Scheme for Drilling Process Using Type-2 Fuzzy Logic
- 2022
-
Ingår i: Algorithms. - : MDPI. - 1999-4893. ; 15:8
-
Tidskriftsartikel (refereegranskat)abstract
- The fault detection system using automated concepts is a crucial aspect of the industrial process. The automated system can contribute efficiently in minimizing equipment downtime therefore improving the production process cost. This paper highlights a novel model based fault detection (FD) approach combined with an interval type-2 (IT2) Takagi–Sugeno (T–S) fuzzy system for fault detection in the drilling process. The system uncertainty is considered prevailing during the process, and type-2 fuzzy methodology is utilized to deal with these uncertainties in an effective way. Two theorems are developed; Theorem 1, which proves the stability of the fuzzy modeling, and Theorem 2, which establishes the fault detector algorithm stability. A Lyapunov stabilty analysis is implemented for validating the stability criterion for Theorem 1 and Theorem 2. In order to validate the effective implementation of the complex theoretical approach, a numerical analysis is carried out at the end. The proposed methodology can be implemented in real time to detect faults in the drilling tool maintaining the stability of the proposed fault detection estimator. This is critical for increasing the productivity and quality of the machining process, and it also helps improve the surface finish of the work piece satisfying the customer needs and expectations.
|
|
| 28. |
- Paul, Satyam, 1981-, et al.
(författare)
-
Discrete Time Sliding Mode Control of Milling Chatter
- 2020
-
Ingår i: ICCSAMA 2019. - Cham : Springer-Verlag New York. - 9783030383633 - 9783030383640 ; , s. 381-390
-
Bokkapitel (refereegranskat)abstract
- The technique of mitigating chatter phenomenon in an effective manner is an important issue from the viewpoint of superior quality machining process with quality production. In this paper, an innovative solution to control chatter vibration actively in the milling process is presented. The mathematical modelling associated with the milling technique is presented in the primary phase of the paper. In this paper, an innovative technique of discrete time sliding mode control(DSMC) is blended with Type 2 fuzzy logic system. Superior mitigation of chatter is the outcome of developed active controller. The Lyapunov scheme is implemented to validate the stability criteria of the proposed controller. The embedded nonlinearity in the cutting forces and damper friction are compensated in an effective manner by the utilization of Type-2 fuzzy technique. The vibration attenuation ability of DSMC-Type-2 fuzzy (DSMC-T2) is compared with the Discrete time PID (D-PID) and DSMC-Type-1 fuzzy (DSMC-T1) for validating the effectiveness of the controller. Finally, the numerical analysis is carried out to validate that DSMC-T2 is superior to D-PID and DSMC-T1 in the minimization of the milling chatter.
|
|
| 29. |
- Paul, Satyam, 1981-, et al.
(författare)
-
Intelligent Fault Detection Scheme for Drilling Process
- 2019
-
Ingår i: ICCMA 2019. - : Institute of Electrical and Electronics Engineers (IEEE). - 9781728137889 - 9781728137872 ; , s. 347-351
-
Konferensbidrag (refereegranskat)abstract
- Automatic fault detection system is an important aspect of industrial process and can contribute significantly for minimizing equipment downtime thus makingit a cost effective process. In this paper, an innovative model-based faultdetection (FD) system in combination with interval type-2 (IT2) Takagi-Sugeno(T-S) fuzzy system is developed for the detection of the faults in the drillbit of the drilling system. The proposed methodology validates the stabilityof the fault detection system in the presence of system uncertainties. Numerical analysis is carried out to prove the effectiveness of the theoretical approach. The effective methodology can be implemented in real time for detecting faults during downhole drilling operations.
|
|
| 30. |
- Reed, Sean, 1982-, et al.
(författare)
-
An efficient algorithm for computing exact system and survival signatures of K-terminal network reliability
- 2019
-
Ingår i: Reliability Engineering & System Safety. - : Elsevier. - 0951-8320 .- 1879-0836. ; 185, s. 429-439
-
Tidskriftsartikel (refereegranskat)abstract
- An efficient algorithm is presented for computing exact system and survival signatures of K-terminal reliability in undirected networks with unreliable edges. K-terminal reliability is defined as the probability that a subset K of the network nodes can communicate with each other. Signatures have several advantages over direct reliability calculation such as enabling certain stochastic comparisons of reliability between competing network topology designs, extremely fast repeat computation of network reliability for different edge reliabilities and computation of network reliability when failures of edges are exchangeable but not independent. Existing methods for computation of signatures for K-terminal network reliability require derivation of cut-sets or path-sets which is only feasible for small networks due to the computational expense. The new algorithm utilises binary decision diagrams, boundary set partition sets and simple array operations to efficiently compute signatures through a factorisation of the network edges. The performance and advantages of the algorithm are demonstrated through application to a set of benchmark networks and a sensor network from an underground mine.
|
|
| 31. |
- Reed, Sean, 1982-, et al.
(författare)
-
Discrete Event Simulation Using Distributional Random Forests to Model Event Outcomes
- 2022
-
Konferensbidrag (refereegranskat)abstract
- In discrete event simulation (DES), the events are random (aleatory) and typically represented by a probability distribution that fits the real phenomena that is studied. The true distributions of event outcomes, which may be multivariate, are often dependent on the values of covariates and this relationship may be complex. Due to difficulties in representing the influence of covariates within DES models, often only the averaged distribution or expected value of the conditional distribution is used. However, this can reduce modelling accuracy and prevent the model from being used to study the influence of covariates. Distributional random forests (DRF) are a machine learning technique for predicting the multivariate conditional distribution of an outcome from the values of covariates using an ensemble of decision trees. In this paper, the benefits of utilizing DRF in DES are explored through comparison with alternative approaches in a model of a powder coating industrial process.
|
|
| 32. |
|
|
| 33. |
- Reed, Sean, et al.
(författare)
-
Estimating the availability of hydraulic drive systems operating under different functional profiles through simulation
- 2015
-
Ingår i: Safety and Reliability. - : Taylor & Francis Group. - 0961-7353 .- 2469-4126. ; 35:2, s. 4-19
-
Tidskriftsartikel (refereegranskat)abstract
- Hydraulic drive systems are widely used in a variety of industrial applications where high torque and low speed rotational power are required. The advantages include maximum torque from zero speed, continuously variable speed within wide limits, high reliability and insensitivity to shock loads. A drive system consists of a hydraulic circuit, electric motors, hydraulic pumps, hydraulic motors and auxiliary components. The stress on the components, and hence wear and failure rate, varies with the torque and speed output by the drive. The reliability of a hydraulic drive system of a particular design can therefore vary significantly between installations operating in applications with different functional requirements. Predicting the availability of a drive system in a particular application is useful for several purposes such as optimising the system design and estimating support costs. This paper describes a simulation model, developed to estimate the availability of a hydraulic drive system in a given functional profile, consisting of output torque and speed time phase requirements. It outputs statistics on system availability and component failure rates. As an example, the simulation model is used to compare these statistics for a drive design operating under two distinct operational profiles.
|
|
| 34. |
|
|
| 35. |
|
|
| 36. |
- Reed, Sean, 1982-, et al.
(författare)
-
Modelling cycle for simulation digital twins
- 2021
-
Ingår i: Manufacturing Letters. - : Elsevier. - 2213-8463. ; 28, s. 54-58
-
Tidskriftsartikel (refereegranskat)abstract
- Digital twins (DT) form part of the Industry 4.0 revolution within manufacturing and related industries. A DT is a digital model (DM) of a real system that features continuous and automated synchronisation and feedback of optimisations between the real and digital domains. A core technology for predictive capabilities from DT is discrete event simulation (DES). The modelling cycle for developing and analysing DES models is significantly different compared to DM. A DT specific DES modelling cycle is introduced that is evolved from that of DM. The availability of specialised software tools for DT tailored to these differences would benefit industry.
|
|
| 37. |
- Reed, Sean, 1982-, et al.
(författare)
-
Modelling stochastic behaviour in simulation digital twins through neural nets
- 2022
-
Ingår i: Journal of Simulation. - : Taylor & Francis. - 1747-7778 .- 1747-7786. ; 16:5, s. 512-525
-
Tidskriftsartikel (refereegranskat)abstract
- In discrete event simulation (DES) models, stochastic behaviour is modelled by sampling random variates from probability distributions to determine event outcomes. However, the distribution of outcomes for an event from a real system is often dynamic and dependent on the current system state. This paper proposes the use of artificial neural networks (ANN) in DES models to determine the current distribution of each event outcome, conditional on the current model state or input data, from which random variates can then be sampled. This enables more realistic and accurate modelling of stochastic behaviour. An application is in digital twin models that aim to closely mimic a real system by learning from its past behaviour and utilising current data to predict its future. The benefits of the approach introduced in this paper are demonstrated through a realistic DES model of load-haul-dump vehicle operations in a production area of a sublevel caving mine.
|
|
| 38. |
- Reed, Sean, 1982-, et al.
(författare)
-
Service support system modelling language for simulation-driven development of functional products
- 2013
-
Ingår i: 2nd International Through-life Engineering Services Conference. - : Elsevier. ; 11, s. 420-424
-
Konferensbidrag (refereegranskat)abstract
- A functional product (FP) comprises of an integrated package of hardware and support services sold under a performance-based contract. A barrier to the adoption of FP is the lack of tools for obtaining predictions of availability and support costs during product development. A previous paper by the authors described a simulation-driven development strategy for designing FP that are optimised for functional availability and support costs. This iterative strategy involves representing the FP design in a modelling language; using a software code to automatically generate and analyse a simulation model from this representation to produce detailed performance predictions; and using these predictions as feedback to improve the design. The use of a modelling language facilitates the representation of the design details within the hardware and support system that influence availability and support costs. This includes the maintenance process design, maintenance strategy design and maintenance resource availability design. In this paper, an overview of a modelling language the authors have developed for this purpose is described.
|
|
| 39. |
- Törlind, Peter, et al.
(författare)
-
Towards true collaboration in global design teams?
- 2005
-
Ingår i: Proceedings ICED 05, the 15th International Conference on Engineering Design. - Barton : Institution of Engineers, Australia. - 0858257882
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Today’s collaboration tools can support formal meetings to a certain extent, though there is still an immense potential for improvement when it comes to designing virtual and physical places where global design teams can collaborate in more ‘natural’ ways than existing distributed environments allow. One challenge for global product development is to support true collaboration within global design teams, where diversity and competences of the whole team can be utilized and where team members can think together rather then merely exchange information, opinions and divide work. This paper summarizes the results of several case studies and development projects performed within the Polhem Laboratory over the last four years and proposes challenges for future research. From our findings some of the most important challenges are how to support users with communication tools for more natural formal and informal communication (i.e. as a co-located team communicates), while automatically storing information and context from the distributed meetings.
|
|
