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- Xu, Fei, et al.
(författare)
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Fatigue Life Prediction for PBGA under Random Vibration Using Updated Finite Element Models
- 2016
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Ingår i: Experimental techniques (Westport, Conn.). - : Springer. - 0732-8818 .- 1747-1567. ; 40:5, s. 1421-1435
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Tidskriftsartikel (refereegranskat)abstract
- A procedure based on finite element (FE) modeling, response surface-based model updating and random vibration analysis is presented to predict the fatigue life of plastic ball grid array (PBGA) components mounted on daisy chain printed circuit board (PCB). A specially designed fixture is used to mimic the typical boundary condition of plug-in PCBs. The FE model is updated through three consecutive stages. In each stage, the first three resonant frequencies are calculated using ANSYS and correlated with modal test results. Two objective functions are created using resonant frequencies and minimized using a multi-objective genetic algorithm (MOGA). The results show that commercial FE software can be used to improve the accuracy of the FE model in a practical way. Random vibration analysis is performed and good agreement with test result is obtained. The resistance of the specially designed daisy chain PCB is monitored. A two-parameter Weibull distribution is used to fit the PBGA failure time. The Von Mises stress power spectral density (PSD) of the critical solder joints is calculated in ANSYS and transferred into time-history data. The rainflow cycle counting (RFCC), the S–N curve and the Miner’s rule are used to estimate the cumulative damage. The calculated fatigue life agrees well with the test results.
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| 2. |
- Zhang, Yan, 1983-
(författare)
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VALUE CO-CREATION FOR SUSTAINABLE PRODUCT SERVICE SYSTEM DESIGN : OPPORTUNITY FOR GLOBAL MANUFACTURING COMPANIES
- 2024
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- There is a gradually spreading servitization trend that is forcing industrial manufacturing companies acting in the global market to rethink their business. Manufacturing companies that were traditionally perceived as product-centered, are today increasingly influenced by a service-oriented theory, which claims that manufacturing companies are driven to shift their business focus towards a strategy where customer-perceived value is in the spotlight, and where products are bundled with services to offer Product-Service Systems (PSS). The need to integrate several knowledge domains (i.e. product development, service development, recycling, etc.) means that industry companies need to move “downstream” knowledge from the entire lifecycle into the early phases of the PSS design process where critical decisions are made. At the same time, this raises the awareness of, and requirements for, methods and tools that support cross-disciplinary team collaboration in the process of designing these PSS solutions. Value co-creation is one strategy to address customer collaboration to develop PSS in a framework that allows different stakeholders to participate in defining design concepts and finding the optimal combination of hardware and service that supplies the desired value. Value co-creation strategy and global collaborative innovation are essential for manufacturing companies to explore new ways of designing PSS.The thesis summarizes the research performed by the author, as an industrial Ph.D. student and director for system innovation at BIGmind Innovation. This thesis aims to study and explore the motivation for, and challenges of, working with value co-creation for PSS design by global manufacturing companies. Firstly, the empirical research determined that there are different challenges that global manufacturing companies and product development face when designing PSS. The work involves exploring value co-creation via a customer collaborative design platform and experience prototyping for product-service system design. The research shows that there is a lack of knowledge about guidelines and processes for collaboration in value co-creation. The research emphasizes that the PSS design methodologies of today neglect to specify the roles and responsibilities of the actors who co-create PSS offerings, and there is a lack of understanding of the entire process and how it is implemented in industrial practice when developing solutions.Conclusions from this work suggest that government policies can make a fast and major impact on the demand for innovations and PSS development. Additionally, a value co-creation approach promotes large-scale user participation in the early phase of PSS design. To enhance stakeholder participation and gather feedback, experiential prototypes were utilized during the conceptual design phase of the PSS design. To support further development in the area of value co-creation, the Future Innovation Framework (FIF) is proposed as a mechanism to facilitate the adoption and use of value co-creation of PSS design. This thesis discusses the implications, opportunities, and challenges of the FIF for industrial PSS design. The thesis concludes with a discussion on the possibility of using value co-creation for PSS design in different industry domains in the future.
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