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Trolle, J., Fagerström, B. & Rosio, C. (2020). Challenges in the Fuzzy Front End of the Production Development Process. In: Advances in Transdisciplinary Engineering, Vol 13: . Paper presented at 9th Swedish Production Symposium, SPS 2020; Virtual, Online; Sweden; 7 October 2020 through 8 October 2020 (pp. 311-322). IOS Press BV
Open this publication in new window or tab >>Challenges in the Fuzzy Front End of the Production Development Process
2020 (English)In: Advances in Transdisciplinary Engineering, Vol 13, IOS Press BV , 2020, p. 311-322Conference paper, Published paper (Refereed)
Abstract [en]

As the demand for customized products increases, manufacturing industries are forced to adapt to rapid changing requirements in product demand by continuously developing new innovative and changeable production systems. In the early phases of production development, there are uncertainty aspects that needs to be managed until freeze of product design and development of a suitable production system. This front end is commonly considered as fuzzy since there is a lack of a structured production development process that supports the uncertain and iterative work that is required to develop feasible production systems in early phases. By identifying these challenges in the fuzzy front end of production development it is possible to inhibit future disturbances in the rest of the process and to increase future production system performance. In the literature, challenges in the latter part of the production development process has been thoroughly examined. However, few empirical investigations have explored the fuzzy front end in production development. The purpose of this study is to investigate challenges in the fuzzy front end of the production development process, focusing on new or comprehensive production system changes. To study these challenges, a multiple case study with 4 cases has been conducted. The empirical investigation consists of 5 semi-structured interviews and 5 participant observations. The findings show multiple challenges closely connected to project pre-conditions and organization structure related factors. Various project uncertainties in this early phase entails challenges to determine valid project objectives, scope and KPIs. Moreover, estimating the right amount of time and resources needed. Complex organization structures may have a significant influence on the way of working resulting in slowness in decision making. Furthermore, various communication challenges are identified which are mainly connected with the incapacity of including all stakeholders early in the development process. 

Place, publisher, year, edition, pages
IOS Press BV, 2020
Keywords
Decision making, Product design, Empirical investigation, Manufacturing industries, Multiple-case study, Organization structures, Participant observations, Product design and development, Production development, Semi structured interviews, Manufacture
National Category
Production Engineering, Human Work Science and Ergonomics
Identifiers
urn:nbn:se:mdh:diva-53018 (URN)10.3233/ATDE200169 (DOI)2-s2.0-85098619962 (Scopus ID)9781614994398 (ISBN)
Conference
9th Swedish Production Symposium, SPS 2020; Virtual, Online; Sweden; 7 October 2020 through 8 October 2020
Available from: 2021-01-14 Created: 2021-01-14 Last updated: 2021-01-14Bibliographically approved
Sjögren, P., Fagerström, B., Kurdve, M. & Lechler, T. (2019). Opportunity discovery in initiated and emergent change requests. Design Science, 5, Article ID e5.
Open this publication in new window or tab >>Opportunity discovery in initiated and emergent change requests
2019 (English)In: Design Science, E-ISSN 2053-4701, Vol. 5, article id e5Article in journal (Refereed) Published
Abstract [en]

When a change request is raised in an engineering project an ad hoc team often forms to manage the request. Prior research shows that practitioners often view engineering changes in a risk-averse manner. As a project progresses the cost of changes increases. Therefore, avoiding changes is reasonable. However, a risk-averse perspective fails to recognize that changes might harbor discoverable and exploitable opportunities. In this research, we investigated how practitioners of ad hoc teams used practices and praxes aimed at discovering and exploiting opportunities in engineering change requests. A single case study design was employed using change request records and practitioner interviews from an engineering project. 87 engineering change requests were analyzed with regards to change triggers, time-to-decision and rejection rate. In total, 25 opportunities were discovered and then 17 exploited. Three practices and six praxes were identified, used by practitioners to discover and exploit opportunities. Our findings emphasize the importance of the informal structure of ad hoc teams, to aid in opportunity discovery. The informal structure enables cross-hierarchal discussions and draws on the proven experience of the team members. Thus, this research guides project managers and presumptive ad hoc teams in turning engineering changes into successful opportunities.

Place, publisher, year, edition, pages
CAMBRIDGE UNIV PRESS, 2019
Keywords
engineering change management, deviation management, uncertainty management, projects-as-practice approach
National Category
Other Engineering and Technologies
Identifiers
urn:nbn:se:mdh:diva-42983 (URN)10.1017/dsj.2019.4 (DOI)000460675300001 ()2-s2.0-85065029288 (Scopus ID)
Projects
INNOFACTURE - innovative manufacturing development
Available from: 2019-03-29 Created: 2019-03-29 Last updated: 2023-05-04Bibliographically approved
Ore, F., Reddy Vemula, B., Hanson, L., Wiktorsson, M. & Fagerström, B. (2019). Simulation methodology for performance and safety evaluation of human-industrial robot collaboration workstation design. INTERNATIONAL JOURNAL OF INTELLIGENT ROBOTICS AND APPLICATIONS, 3(3), 269-282
Open this publication in new window or tab >>Simulation methodology for performance and safety evaluation of human-industrial robot collaboration workstation design
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2019 (English)In: INTERNATIONAL JOURNAL OF INTELLIGENT ROBOTICS AND APPLICATIONS, ISSN 2366-5971, Vol. 3, no 3, p. 269-282Article in journal (Refereed) Published
Abstract [en]

There is a strong interest in the scope of human-industrial robot collaboration (HIRC) in manufacturing industry for greater flexibility and productivity. However, HIRC in manufacturing is still in its infancy; industrial practitioners have many apprehensions and uncertainties concerning the system's performance and human operators' safety. Therefore, there is a need for investigations into design processes and methods to make sure the designed HIRC workstations successfully meet design guidelines on system performance, human safety and ergonomics for practical industrial applications. This research proposes a HIRC workstation design process. The novelty of this design process is the methodology to evaluate the HIRC workstation design alternatives by considering both performance and safety characteristics through computer-based simulations. As a proof of concept, the proposed HIRC design process is applied on an industrial manufacturing case from a heavy-vehicle manufacturing company.

Keywords
Human industrial robot collaboration, Safety, Ergonomics, Collision model, Performance evaluation, Risk assessment
National Category
Mechanical Engineering
Identifiers
urn:nbn:se:mdh:diva-45373 (URN)10.1007/s41315-019-00097-0 (DOI)000486179900003 ()2-s2.0-85075361362 (Scopus ID)
Projects
INNOFACTURE - innovative manufacturing development
Available from: 2019-10-03 Created: 2019-10-03 Last updated: 2020-11-02Bibliographically approved
Raza, M., Silva, P., Irwin, M., Fagerström, B. & Jarfors, A. E. W. (2018). Effects of process related variations on defect formation in investment cast components. Archives of Foundry Engineering, 18(1), 103-108
Open this publication in new window or tab >>Effects of process related variations on defect formation in investment cast components
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2018 (English)In: Archives of Foundry Engineering, ISSN 1897-3310, E-ISSN 2299-2944, Vol. 18, no 1, p. 103-108Article in journal (Refereed) Published
Abstract [en]

Castability of thin-walled castings is sensitive to variation in casting parameters. Variation in casting parameters can lead to undesired casting conditions which result in defect formation. Variation in rejection rate due to casting defects from one batch to another is a common problem in foundries and the cause of this variation is usually not well understood due to the complexity of the process. In this work, variation in casting parameters resulting from human involvement in the process is investigated. Casting practices of different groups of operators were evaluated and resulting variations in casting parameters were observed and analyzed. The effect of these variations was evaluated by comparing the rejection statistics for each group. In order to minimize process variation, optimized casting practices were implemented by developing specific process instructions for the operators. The significance of variation in casting parameters in terms of their impact on foundry rejections was evaluated by comparing the number of rejected components before and after implementation of optimized casting practices. It was concluded that variation in casting parameters due to differences in casting practices of various groups of operators has significant impact on casting quality. Variation in mould temperature, melt temperature and pouring rate due to differences in handling time and operator practice resulted in varying quality of components between batches. By implementing an optimized standard casting instruction, both quality and process reliability were improved significantly.

National Category
Production Engineering, Human Work Science and Ergonomics
Identifiers
urn:nbn:se:mdh:diva-38768 (URN)10.24425/118820 (DOI)000435927100019 ()2-s2.0-85046717206 (Scopus ID)
Projects
INNOFACTURE - innovative manufacturing development
Available from: 2018-02-27 Created: 2018-02-27 Last updated: 2020-10-20Bibliographically approved
Raza, M., Svenningsson, R., Irwin, M., Fagerström, B. & Jarfors, A. E. W. (2018). EFFECTS OF PROCESS RELATED VARIATIONS ON FILLABILITY SIMULATION OF THIN-WALLED IN718 STRUCTURES (vol 12, pg 543, 2018) [Letter to the editor]. International Journal of metalcasting, 12(4), 927-927
Open this publication in new window or tab >>EFFECTS OF PROCESS RELATED VARIATIONS ON FILLABILITY SIMULATION OF THIN-WALLED IN718 STRUCTURES (vol 12, pg 543, 2018)
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2018 (English)In: International Journal of metalcasting, ISSN 1939-5981, E-ISSN 2163-3193, Vol. 12, no 4, p. 927-927Article in journal, Letter (Other academic) Published
Abstract [en]

The following are errors in the original article. All are corrected as reflected.

Place, publisher, year, edition, pages
SPRINGER INTERNATIONAL PUBLISHING AG, 2018
Identifiers
urn:nbn:se:mdh:diva-46352 (URN)10.1007/s40962-018-0223-6 (DOI)000446725000023 ()2-s2.0-85054789346 (Scopus ID)
Projects
INNOFACTURE - innovative manufacturing development
Available from: 2019-12-13 Created: 2019-12-13 Last updated: 2020-10-22Bibliographically approved
Raza, M., Svenningsson, R., Irwin, M., Fagerström, B. & Jarfors, A. (2018). Effects of Process Related Variations on Fillablity Simulation of Thin-Walled IN718 Structures. International Journal of metalcasting, 12(3), 543-553
Open this publication in new window or tab >>Effects of Process Related Variations on Fillablity Simulation of Thin-Walled IN718 Structures
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2018 (English)In: International Journal of metalcasting, ISSN 1939-5981, E-ISSN 2163-3193, Vol. 12, no 3, p. 543-553Article in journal (Refereed) Published
Abstract [en]

Due to the ability to produce net shape parts that maintain tight dimensional tolerances, investment casting has been widely used to manufacture components used in the hot gas path in gas turbines since 1950’s.1 In the power generation and aerospace industries, the overall weight reduction of engineering systems is much sought after, especially for turbines. Weight reduction of an engineering system can be achieved by using integrated multifunction components or by reducing component weight either by improving component design or using lightweight materials. Increased demands have been put on investment casting foundries by the turbine industry to produce complex thin-walled components.2 Weight reduction of components is essential to lower fuel consumption and reduce environmental impact.3 Casting of thin-sections is challenging due to premature solidification in thin-walled sections and long feeding distances often resulting in incomplete filling, cold shuts and shrinkage porosity.4 A number of studies have been performed to investigate important aspects of investment casting of thin-walled geometries. Flemings5 demonstrated that superheat and metal head had greater effect on fluidity than melt viscosity and surface tension for thicker sections. Flemings5 also concluded that for thin sections surface tension became important, limiting mold filling. For the nickel base superalloys (IN100 alloy), Chandraseckariah and Seshan6 concluded that the pouring temperature and mold temperature had greater effect on fluidity than other casting variables, such as, vacuum level and shell thickness. In an attempt to address the additional challenges imposed by thin-walled castings, Campbell and Oliff7 established mould filling criteria for thin walled castings. It was shown that at low heat content in a vertical mould set-up fluidity was limited by solidification which they termed flowability, a dynamic aspect, whereas at high heat content of a vertical mould system, fluidity was limited by surface tension which they termed as fillabillity, a static aspect. Campbell8 also performed investigations on the effect of capillary repulsion in thin-section moulds and surface tension on the filling pattern in the mould cavity. It was suggested that the surface oxide films formed during filling were pinned to the mould wall blocking the melt flow, resulting in decreased fluidity. These films also caused cold shuts and other internal defects in castings. Campbell9 established gating design requirements for thin-walled castings by investigating the effect of different gating methods and their effect on fillability in thin-walled castings. Bottom-gating was concluded superior to top-gated systems and bottom-gating reduced the filling instabilities. The prediction by simulation has become a vital step in the development of efficient manufacturing processes. The reliability of simulation is significantly dependent upon material properties, metallurgical models as well as accuracy in defining boundary condition.10 The boundary conditions are influenced by equipment and operation related variations arising from mould handling and melt pouring.11 Other parameters such as the mould filling sequence in casting of multi-cavity moulds are related to cluster design and equipment related limitation in process control tolerances. The degree of variation in critical process parameters is also highly dependent on the degree of automation. The relative importance of these process uncertainties on casting quality is not well understood. Although the physical principles governing fill and solidification are well established,12 it is difficult to account for uncertainties in process parameters when defining boundary conditions for simulations. As concluded in a related study,13 there is a lack of literature available that addresses the effect of variation in process parameters on the accuracy of simulation. This suggests a need for further investigation of how to define boundary conditions that more accurately describe the conditions in the foundry. The aim of this research is to investigate how the uncertainty in variation of foundry parameters can be accounted for when defining initial boundry conditions in order to improve accuracy of simulation. Characterization measurement has been performed on mould and alloy materials to eliminate uncertainties that can potentially be introduced in simulation from inaccurate material data. The discrepancy between experiments and simulations were analyzed and discussed to identify how variation in foundry parameters influence accuracy in simulation of the filling of a thin-walled mould.

Place, publisher, year, edition, pages
Sweden: Springer, 2018
Keywords
casting thin-walled filling simulation prediction inconel
National Category
Production Engineering, Human Work Science and Ergonomics
Identifiers
urn:nbn:se:mdh:diva-38643 (URN)10.1007/s40962-017-0189-9 (DOI)000436927100014 ()2-s2.0-85049332591 (Scopus ID)1939-5981 (ISBN)
Projects
INNOFACTURE - innovative manufacturing development
Available from: 2018-02-27 Created: 2018-02-27 Last updated: 2020-12-22Bibliographically approved
Sjögren, P., Fagerström, B., Kurdve, M. & Callavik, M. (2018). Managing emergent changes: ad hoc teams' praxis and practices. International Journal of Managing Projects in Business/Emerald, 11(4), 1086-1104
Open this publication in new window or tab >>Managing emergent changes: ad hoc teams' praxis and practices
2018 (English)In: International Journal of Managing Projects in Business/Emerald, ISSN 1753-8378, E-ISSN 1753-8386, Vol. 11, no 4, p. 1086-1104Article in journal (Refereed) Published
Abstract [en]

Purpose The purpose of this paper is to explore how emergent changes are handled in research and development (R&D) projects. R&D projects' business potential lies in their exploration of the unknown; conversely, this makes them uncertain endeavours, prone to emergent changes. Design/methodology/approach Uses a single-case-study design, based on a projects-as-practice perspective and a soft systems methodology (SSM) analysis, to map how ad hoc R&D teams handle emergent changes, specifically the solution identification and assessment phase and the implementation plan. An R&D project in the power industry, involving over 250 engineers, was analysed. Findings This paper shows how emergent changes are handled differently from initiated changes during the decision-making phase. The system analysis shows that the most critical factors for managing these changes are: collective reflection between project parties; and including experienced engineers in implementation-plan reviews. Practical implications The results are of relevance both to R&D managers aiming to improve team performance and to general project management. Informal notions of emergent changes can be formalised in the change request process. Weaknesses in the project team's organisation are highlighted, and details of how of how to mitigate these are provided. Originality/value Combines engineering-design and project-management research on emergent changes, adding to the former regarding people-organisational and strategic issues. Furthers understanding of the projects-as-practice approach and emergent change (deviations) handling by ad hoc teams in a project environment. SSM has not previously been used to explore aspects of projects-as-practice, and this is a novel way of adding to the body of knowledge on project praxis and practise.

Place, publisher, year, edition, pages
EMERALD GROUP PUBLISHING LTD, 2018
Keywords
Project management, Research and development, Emergent change, Soft systems methodology, Ad hoc teams
National Category
Production Engineering, Human Work Science and Ergonomics
Identifiers
urn:nbn:se:mdh:diva-40561 (URN)10.1108/IJMPB-12-2017-0163 (DOI)000441516600012 ()2-s2.0-85049525820 (Scopus ID)
Projects
INNOFACTURE - innovative manufacturing development
Available from: 2018-08-30 Created: 2018-08-30 Last updated: 2020-10-20Bibliographically approved
Reddy Vemula, B., Ramteen, M., Spampinato, G. & Fagerström, B. (2017). Human-robot impact model: For safety assessment of collaborative robot design. In: Proceedings - 2017 IEEE 5th International Symposium on Robotics and Intelligent Sensors, IRIS 2017: . Paper presented at IRIS 2017 IRIS 2017 IEEE, 05 Oct 2017, Ottawa, Canada (pp. 236-243).
Open this publication in new window or tab >>Human-robot impact model: For safety assessment of collaborative robot design
2017 (English)In: Proceedings - 2017 IEEE 5th International Symposium on Robotics and Intelligent Sensors, IRIS 2017, 2017, p. 236-243Conference paper, Published paper (Refereed)
Abstract [en]

In this research, a novel impact simulation model based on compliant contact force (CCF) modelling approach is presented. This model can simulate the physical impact between non-homogeneous and layered elastic bodies representing the robot and human body parts. The proposed CCF model is intended to be used by the robot designers to execute safety evaluation tasks during the design and development of collaborative robot systems. The main theoretical contribution from this CCF impact model is related to the formulations, which can account for the contact behavior due to the non-homogeneous nature of the impacting bodies. The relevance of the proposed impact simulation is evaluated based on a comparative analysis with other available relevant models from the literature as well as with Finite element based simulation model. Finally, the influence of various robot design parameters on the impact severity is analyzed for different impact scenarios by adopting the proposed CCF model.

National Category
Robotics and automation
Identifiers
urn:nbn:se:mdh:diva-38642 (URN)10.1109/IRIS.2017.8250128 (DOI)000425844300039 ()2-s2.0-85047377747 (Scopus ID)978-1-5386-1342-9 (ISBN)
Conference
IRIS 2017 IRIS 2017 IEEE, 05 Oct 2017, Ottawa, Canada
Projects
INNOFACTURE - innovative manufacturing development
Available from: 2018-03-02 Created: 2018-03-02 Last updated: 2025-02-09Bibliographically approved
Raza, M., Svenningsson, R., Irwin, M., Fagerström, B. & Jarfors, A. E. W. (2017). Simulation based process design approach for manufacturing of light-weight cast components. In: : . Paper presented at LIGHTer International Conference 2017, 22-23 November 2017, Gothenburg, Sweden.
Open this publication in new window or tab >>Simulation based process design approach for manufacturing of light-weight cast components
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2017 (English)Conference paper, Published paper (Refereed)
Abstract [en]

Weight reduction of engineering systems, especially for turbines is desirable due to global requirements for lower fuel consumption and emissions. The resulting design modifications by system manufacturers place demands on foundries to be able to cast thin-walled and complex hot-gas-path components with consistent quality and shorter lead times. The ability to cast components in thinner sections can result in overall weight reduction of turbines. Casting of thin-sections is challenging due to faster solidification and is sensitive to variation in critical process parameters in the foundry. The aim of this work is to develop a framework using design of experiments and simulation to develop a robust casting process as an alternative to costly trial and error that are frequently applied. The Distance based response surface method (RSM) is used to make a Design of experiments (DoE). By using a simulation tool that replicates the process conditions, the test iterations were simulated and regression analysis of the shrinkage and misrun values predicted by the model was performed to determine the effect of casting conditions on defect formation. The optimization of the process conditions was done by adjusting ranges and targets for the response and optimal conditions were proposed for casting.

National Category
Production Engineering, Human Work Science and Ergonomics
Identifiers
urn:nbn:se:mdh:diva-38770 (URN)
Conference
LIGHTer International Conference 2017, 22-23 November 2017, Gothenburg, Sweden
Projects
INNOFACTURE - innovative manufacturing development
Available from: 2018-02-27 Created: 2018-02-27 Last updated: 2020-10-20Bibliographically approved
Sjögren, P., Fagerström, B., Kurdve, M. & Thomas, L.Opportunity discovery in initiated and emergent change requests.
Open this publication in new window or tab >>Opportunity discovery in initiated and emergent change requests
(English)Manuscript (preprint) (Other academic)
Abstract [en]

In this research, we analyze practitioner practices and praxes associated with discovering and exploiting opportunities in project-based change requests. Change requests are the aggregation of engineering changes and are considered in a redesign process. Raising a change request initiates the formation of an ad hoc team to manage it. A single case study design was employed using change request records and practitioner interviews from an engineering project. Additionally, the collected data was used to analyze discovered and exploited opportunities from a projects-as-practice perspective. Prior research on change requests has shown that practitioners often view changes in a risk-averse manner. However, a risk-averse mindset does not encompass opportunities. Our findings emphasize the importance of the informal structure of ad hoc teams, as opposed to formal structures, to aid in opportunity discovery. The informal structure enables cross-hierarchal discussions among team members and draws on the proven experience of the team members. Finally, the dynamic, dual structure of ad hoc teams (engineering and on-site teams) is an essential part of opportunity discovery. Adding to the existing knowledge in the field of engineering change management, we present a framework that supports practitioners in identifying how to turn engineering changes into successful opportunities. 

Keywords
engineering change management; deviation management; uncertainty management; projects-as-practice method
National Category
Engineering and Technology Production Engineering, Human Work Science and Ergonomics
Research subject
Innovation and Design
Identifiers
urn:nbn:se:mdh:diva-40917 (URN)
Note

conditionally accepted

Available from: 2018-09-12 Created: 2018-09-12 Last updated: 2018-12-05Bibliographically approved
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ORCID iD: ORCID iD iconorcid.org/0000-0002-7816-1213

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