| 1. |
- Almeida, Diogo, 1991-, et al.
(författare)
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Cooperative Manipulation and Identification of a 2-DOF Articulated Object by a Dual-Arm Robot
- 2018
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Ingår i: 2018 IEEE INTERNATIONAL CONFERENCE ON ROBOTICS AND AUTOMATION (ICRA). - 1050-4729. - 9781538630815 ; , s. 5445-5451
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Konferensbidrag (refereegranskat)abstract
- In this work, we address the dual-arm manipula-tion of a two degrees-of-freedom articulated object that consistsof two rigid links. This can include a linkage constrainedalong two motion directions, or two objects in contact, wherethe contact imposes motion constraints. We formulate theproblem as a cooperative task, which allows the employment ofcoordinated task space frameworks, thus enabling redundancyexploitation by adjusting how the task is shared by the robotarms. In addition, we propose a method that can estimate thejoint location and the direction of the degrees-of-freedom, basedon the contact forces and the motion constraints imposed bythe object. Experimental results demonstrate the performanceof the system in its ability to estimate the two degrees of freedomindependently or simultaneously.
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| 2. |
- Grönstedt, Tomas, 1970, et al.
(författare)
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Multidisciplinary assessment of a year 2035 turbofan propulsion system
- 2022
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Ingår i: 33rd Congress of the International Council of the Aeronautical Sciences, ICAS 2022. - : International Council of the Aeronautical Sciences. - 9781713871163 ; 7, s. 4981-4990
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Konferensbidrag (refereegranskat)abstract
- A conceptual design of a year 2035 turbofan is developed and integrated onto a year 2035 aircraft model. The mission performance is evaluated for CO2, noise and NOx and is compared with a notional XWB/A350-model. An OGV heat exchanger is then studied rejecting heat from an electric generator, and its top-level performance is evaluated. The fan, the booster and the low-pressure turbine of the propulsion system are subject to more detailed aero design based on using commercial design tools and CFD-optimization. Booster aerodynamic modelling output is introduced back into the performance model to study the integrated performance of the component. The top-level performance aircraft improvements are compared to top-level-trends and ICAO estimates of technology progress potential, attempting to evaluate whether there is some additional margin for efficiency improvement beyond the ICAO technology predictions for the same time frame.
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| 3. |
- Honfi, Daniel, et al.
(författare)
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Decision support for maintenance and upgrading of existing bridges
- 2017
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Ingår i: IABSE Conference, Vancouver 2017. - : International Association for Bridge and Structural Engineering (IABSE). - 9783857481536 ; 109, s. 336-345, s. 336-345
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Konferensbidrag (refereegranskat)abstract
- Maintenance of transportation infrastructure assets can be relatively expensive, since it does not only include the direct cost of interventions, but also the indirect consequences of traffic disruptions. To make optimal decisions about maintenance actions, including rehabilitation and upgrading, reliable information about the performance of existing structures is needed. However, obtaining such information might require significant efforts and can be done in various ways. The purpose of an ongoing Swedish research project BIG BRO is to develop a framework for a decision support methodology that can be used for implementing maintenance strategies for bridges on a rational basis. The present paper provides a brief overview about the project as well as describes some of the ongoing work.
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| 4. |
- Johansson, Jakob, et al.
(författare)
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Screening Environmental Impact Reduction Enabled by Brass Reclamation through Hot Forging Operations
- 2020
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Ingår i: SPS2020 - Proceedings of the Swedish Production Symposium. - : IOS Press. - 9781614994398 ; 13, s. 241-248, s. 241-248
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Konferensbidrag (refereegranskat)abstract
- The traditional method for recycling brass chips is to send the scrap back to the material manufacturer for re-melting. Alternatively, brass chips can be reclaimed through hot forging operations at the production site. As an initial screening of the environmental impact of this novel reclamation method, the impacts of this new method was compared to conventional brass production (including recycling) for a specific part. These two production routes were compared in terms of cumulative energy demand and climate change impact. The comparison between the two production routes showed that the new reclamation method reduced the cumulative energy demand with 29 % and climate change impact with 30 % for production of a specific part compared to conventional recycling. It is, however, important to note that the material produced using hot forging reclamation method have slightly lower mechanical properties as compared to the traditionally recycled material. Currently the novel recycling method is only tested in lab scale and therefore, further studies are needed in order to fully assess the environmental impacts of the new reclamation method compared to conventional brass production.
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| 5. |
- Karayiannidis, Yiannis, 1980, et al.
(författare)
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Operational space robot control for motion performance and safe interaction under Unintentional Contacts
- 2016
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Ingår i: 2016 European Control Conference (ECC);Aalborg, Denmark, 29 June - 1 July 2016. - : Institute of Electrical and Electronics Engineers Inc.. ; , s. 407-412, s. 407-412, s. 407-412
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Konferensbidrag (refereegranskat)abstract
- A control law achieving motion performance of quality and compliant reaction to unintended contacts for robot manipulators is proposed in this work. It achieves prescribed performance evolution of the position error under disturbance forces up to a tunable level of magnitude. Beyond this level, it deviates from the desired trajectory complying to what is now interpreted as unintentional contact force, thus achieving enhanced safety by decreasing interaction forces. The controller is a passivity model based controller utilizing an artificial potential that induces vanishing vector fields. Simulation results with a three degrees of freedom (DOF) robot under the control of the proposed scheme, verify theoretical findings and illustrate motion performance and compliance under an external force of short duration in comparison with a switched impedance scheme.
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| 6. |
- Landström, Anna, 1990, et al.
(författare)
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A life cycle approach to business performance measurement systems
- 2018
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Ingår i: Procedia Manufacturing. - : Elsevier BV. - 2351-9789. ; 25, s. 126-133, s. 126-133
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Konferensbidrag (refereegranskat)abstract
- Virtually every company has implemented a Business Performance Measurement System (BPMS) with the purpose of monitoring production and business performance and to execute the corporate strategy at all levels in a company. The purpose of this article is to shed light on common pitfalls related to the practical use of BPMS and further to present a life cycle model with the purpose of introducing structured approach to avoiding the pitfalls. The article contributes to further development of the BPMS life cycle concept and practical examples of how it can be used.
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| 7. |
- Lejon, Marcus, 1986, et al.
(författare)
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Multidisciplinary Design of a Three Stage High Speed Booster
- 2017
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Ingår i: ASME Turbo Expo 2017: Turbine Technical Conference and Exposition. - : ASME Press. ; 2B-2017
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Konferensbidrag (refereegranskat)abstract
- The paper describes a multidisciplinary conceptual design of an axial compressor, targeting a three stage, high speed, high efficiency booster with a design pressure ratio of 2.8. The paper is outlined in a step wise manner starting from basic aircraft and engine thrust requirements, establishing the definition of the high speed booster interface points and its location in the engine. Thereafter, the aerodynamic 1D/2D design is carried out using the commercial throughflow tool SC90C. A number of design aspects are described, and the steps necessary to arrive at the final design are outlined. The SC90C based design is then carried over to a CFD based conceptual design tool AxCent, in which a first profiling is carried out based on a multiple circular arc blade definition. The design obtained at this point is referred to as the VINK compressor. The first stage of the compressor is then optimized using an in-house optimization tool, where the objective functions are evaluated from detailed CFD calculations. The design is improved in terms of efficiency and in terms of meeting the design criteria put on the stage in the earlier design phases. Finally, some aeromechanical design aspects of the first stage are considered. The geometry and inlet boundary conditions of the compressor are shared with the turbomachinery community on a public server. This is intended to be used as a test case for further optimization and analysis.
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| 8. |
- Reifarth, R., et al.
(författare)
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Nuclear astrophysics with radioactive ions at FAIR
- 2016
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Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 665:1
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Konferensbidrag (refereegranskat)abstract
- The nucleosynthesis of elements beyond iron is dominated by neutron captures in the s and r processes. However, 32 stable, proton-rich isotopes cannot be formed during those processes, because they are shielded from the s-process flow and r-process beta-decay chains. These nuclei are attributed to the p and rp process. For all those processes, current research in nuclear astrophysics addresses the need for more precise reaction data involving radioactive isotopes. Depending on the particular reaction, direct or inverse kinematics, forward or time-reversed direction are investigated to determine or at least to constrain the desired reaction cross sections. The Facility for Antiproton and Ion Research (FAIR) will offer unique, unprecedented opportunities to investigate many of the important reactions. The high yield of radioactive isotopes, even far away from the valley of stability, allows the investigation of isotopes involved in processes as exotic as the r or rp processes.
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| 9. |
- Theorin, Alfred, et al.
(författare)
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An Event-Driven Manufacturing Information System Architecture
- 2015
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Ingår i: 15th IFAC Symposium onInformation Control Problems inManufacturing - INCOM 2015. - : Elsevier BV. ; 48:3, s. 547-554
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Konferensbidrag (refereegranskat)abstract
- Future manufacturing systems need to be more flexible, to embrace tougher and constantly changing market demands. They also need to make better use of plant data, ideally utilizing all data from the entire plant. Low-level data should be refined to real-time information for decision making, to facilitate competitiveness through informed and timely decisions. The Line Information System Architecture, LISA, is designed to enable flexible factory integration and data utilization. In LISA, international standards and established off-the-shelf technologies have been combined with the main objective to be industrially applicable. LISA is an event-driven architecture with a prototype-oriented information model and formalized transformation services. It features loose coupling, flexibility, and ease of retrofitting legacy devices. The architecture has been evaluated on both real industrial data and industrial demonstrators and is also being installed at a large automotive company.
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| 10. |
- Zackrisson, Mats, et al.
(författare)
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Sustainability Performance Indicators at Shop Floor Level in Large Manufacturing Companies
- 2017
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Ingår i: The 24th CIRP Conference on Life Cycle Engineering. - : Elsevier. ; 61, s. 457-462
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Konferensbidrag (refereegranskat)abstract
- This article investigates sustainability in the performance measurement systems of Swedish manufacturing companies. It builds on a previous study that documents relatively few direct environmental indicators at shop floor level, which raises questions about possible indirect links between existing indicators and the environment that could be used to improve the environmental aspect of company's sustainability ambitions. A method for identifying and categorizing indirect links to sustainability issues was defined and used. The results suggest that at shop floor level 90% of the indicators have at least an indirect relation to one or more of the sustainability dimensions economy, environment and social, of which 26% are at least indirectly related to the environmental dimension. Despite the many indirect connections, participating companies perceive a need to improve sustainability indicators and some ideas are suggested.
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