| 1. |
- Blomé, Mikael, et al.
(author)
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Visualisation of Human Characteristics in Vehicle and Health Care Product Development
- 2007
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In: SIGRAD 2007 Conference Proceedings. - Linköping : Linköping University Electronic Press. - 1650-3686. - 9789173939904 ; , s. 31-34
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Conference paper (peer-reviewed)abstract
- The purpose of the research project described in this paper is to improve the efficiency of product development processes by exchanging knowledge and experiences about user centred design methods and technologies between the two branches: vehicle and health care industries. The health care industry can benefit from visualisation and simulation tools that include computer manikins, a physical representation of the human, and the vehicle industry can benefit from manikins having personal characteristics, which has proven to be successful in the health care industry.
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| 2. |
- Bäckstrand, Gunnar, et al.
(author)
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Reduce of ergonomics design flaws through virtual methods.
- 2007
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In: Proceedings of the 39th annual Nordic Ergonomic Society Conference, Lysekil, Sweden, October 1-3, CD-ROM.. - : Nordic Ergonomics Society.
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Conference paper (peer-reviewed)abstract
- A work method for product and production system development that includes virtual methods for ergonomics analysis is presented and argued.The proposed work method is described and illustrated with an example,which the authors believe shows how a virtual work method can contributeto a better workplace design, and thereby, if utilised, would have prevented some of the design flaws that existed in the actual final product design in the example. This paper will also present the outcome, gain, and setbacks thatare connected to the use of virtual work analysis methods within a design process.
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| 3. |
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| 4. |
- Högberg, Dan, et al.
(author)
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Industrial customisation of digital human modelling tools
- 2008
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In: International Journal of Services Operations and Informatics. - : InderScience Publishers. - 1741-539X .- 1741-5403. ; 3:1, s. 53-70
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Journal article (peer-reviewed)abstract
- Computer aided visualisation and simulation enables earlyevaluation of important design parameters of future products and productionsystems. Typically, humans affect the system performance, and in order toachieve the expected system efficiency ergonomics needs to be considered inthe design process in addition to the more technical or logistical matters.Hence, there is a call for ergonomics to be a natural part of the product andproduction development process, also at virtual stages. Three examples of thedevelopment of Digital Human Modelling-(DHM)-based company-specific
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| 5. |
- Högberg, Dan, et al.
(author)
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Industrial customisation of digital human modelling tools
- 2008
-
In: International Journal of Services Operations and Informatics. - 1741-5403 .- 1741-539X. ; 3:1, s. 53-70
-
Journal article (peer-reviewed)abstract
- Computer aided visualization and simulation enables early evaluation of important design parameters of future products and production systems. Typically, humans affect the system performance, and in order to achieve the expected system efficiency ergonomics needs to beconsidered in the design process in addition to the more technical or logistical matters. Hence, there is a call for ergonomics to be a natural part of the product and production development process,also at virtual stages. Three examples of the development of DHM (digital human modelling) based company-specific ergonomics evaluation methods and work processes are portrayed, argued anddiscussed. These illustrate the use of DHM tools for performing static work and occupantpackaging analyses, as well as customizing activities made for the implementation of the tools in companies’ work processes. This is followed by a discussion of future needs of DHM tools including the call for ergonomics methods for evaluating full work cycles.
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| 6. |
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| 7. |
- Högberg, Dan, et al.
(author)
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Representing the elderly in digital human modelling
- 2008
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In: The 40th annual Nordic Ergonomic Society Conference, NES 2008, Reykjavík, Iceland, August 11-13.. - Kópavogur : Vinnuvistfræðifélag Íslands.
-
Conference paper (peer-reviewed)abstract
- Digital human modelling (DHM) tools have been introduced in industry, mainly in automotive, aerospace and industrial engineering, to facilitate a proactive and efficient consideration of ergonomics in the design process. The employment of DHM tools in the health care sector calls for customisation work to be carried out in order to make the tools fit the design activities. The human model, i.e. the computer manikin, needs to be modified since it has the characteristics and appearance of an able healthy young or middle-aged human, but the resident or patient is frequently an elderly person with impairments of some kind. This paper suggests concepts and structures for assigning the computer manikins characteristics of the elderly. These changes are made by the modification of anthropometric and joint range of motion data in the DHM tool, and by assigning narrative descriptions to themanikins and more age-corresponding appearances. The objective is to define a manageable number of representative manikins that will support a proactive and user-centred design process in the health care industry, and in other types of design processes for the elderly, or in an inclusive design context.
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| 8. |
- Högberg, Dan, et al.
(author)
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Towards Dynamic Ergonomics Analysis of Work Sequences in Virtual Environments
- 2007
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In: Proceedings of the 17th International Conference on Flexible Automation and Intelligent Manufacturing (2007 FAIM), Philadelphia, USA, June 2007. - 9781427620927 - 142762092X ; , s. 581-588
-
Conference paper (peer-reviewed)abstract
- Computer aided visualization and simulation enables early assessment of important design parameters of future products and production systems. Typically, humans affect the system performance, and in order to achieve the expected system efficiency ergonomics needs to be considered in the design process in addition to the more technical or logistical matters. Hence, there is a call for ergonomics to be a natural part of the product and production system design process, also at virtual stages. This paper portrays and discusses two cases where company-specific ergonomics guidelines were implemented into digital human modeling systems for performing static work analyses. Albeit useful, the approach of evaluating static postures gives a reduced picture of the actual situation since the work usually involves a series of movements and tasks. A recently commenced research project aims to enhance knowledge on how to estimate accumulated ergonomic load over time. This knowledge is eventually to be implemented in DHM tools to support objective ergonomics analysis of complete work sequences in virtual environments.
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| 9. |
- Iriondo Pascual, Aitor, 1993-, et al.
(author)
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Enabling Knowledge Discovery in Multi-Objective Optimizations of Worker Well-Being and Productivity
- 2022
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In: Sustainability. - : MDPI. - 2071-1050. ; 14:9
-
Journal article (peer-reviewed)abstract
- Usually, optimizing productivity and optimizing worker well-being are separate tasks performed by engineers with different roles and goals using different tools. This results in a silo effect which can lead to a slow development process and suboptimal solutions, with one of the objectives, either productivity or worker well-being, being given precedence. Moreover, studies often focus on finding the best solutions for a particular use case, and once solutions have been identified and one has been implemented, the engineers move on to analyzing the next use case. However, the knowledge obtained from previous use cases could be used to find rules of thumb for similar use cases without needing to perform new optimizations. In this study, we employed the use of data mining methods to obtain knowledge from a real-world optimization dataset of multi-objective optimizations of worker well-being and productivity with the aim to identify actionable insights for the current and future optimization cases. Using different analysis and data mining methods on the database revealed rules, as well as the relative importance of the design variables of a workstation. The generated rules have been used to identify measures to improve the welding gun workstation design.
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| 10. |
- Iriondo Pascual, Aitor, 1993-, et al.
(author)
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Multi-objective Optimization of Ergonomics and Productivity by Using an Optimization Framework
- 2022
-
In: Proceedings of the 21st Congress of the International Ergonomics Association (IEA 2021). - Cham : Springer. - 9783030746131 - 9783030746148 ; , s. 374-378
-
Conference paper (peer-reviewed)abstract
- Simulation technologies are widely used in industry as they enable efficient creation, testing, and optimization of the design of products and production systems in virtual worlds, rather than creating,testing, and optimizing prototypes in the physical world. In an industrial production context, simulation of productivity and ergonomics helps companies to find and realize optimized solutions that uphold profitability, output, quality, and worker well-being in their production facilities. However, these two types of simulations are typically carried out using separate software, used by different users, with different objectives. This easily causes silo effects, leading to slow development processes and sub-optimal solutions. This paper reports on research related to the realization of an optimization framework that enables the concurrent optimization of aspects relating to both ergonomics and productivity. The framework is meant to facilitate the inclusion of Ergonomics 4.0 in the Industry 4.0 revolution.
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| 11. |
- Iriondo Pascual, Aitor, 1993-, et al.
(author)
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Optimization of Productivity and Worker Well-Being by Using a Multi-Objective Optimization Framework
- 2021
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In: IISE Transactions on Occupational Ergonomics and Human Factors. - : Taylor & Francis. - 2472-5838 .- 2472-5846. ; 9:3-4, s. 143-153
-
Journal article (peer-reviewed)abstract
- OCCUPATIONAL APPLICATIONSWorker well-being and overall system performance are important elements in the design of production lines. However, studies of industry practice show that current design tools are unable to consider concurrently both productivity aspects (e.g., line balancing and cycle time) and worker well-being related aspects (e.g., the risk of musculoskeletal disorders). Current practice also fails to account for anthropometric diversity in the workforce and does not use the potential of multi-objective simulation-based optimization techniques. Accordingly, a framework consisting of a workflow and a digital tool was designed to assist in the proactive design of workstations to accommodate worker well-being and productivity. This framework uses state-of-the-art optimization techniques to make it easier and quicker for designers to find successful workplace design solutions. A case study to demonstrate the framework is providedTECHNICAL ABSTRACTRationale: Simulation technologies are used widely in industry as they enable efficient creation, testing, and optimization of the design of products and production systems in virtual worlds. Simulations of productivity and ergonomics help companies to find optimized solutions that maintain profitability, output, quality, and worker well-being. However, these two types of simulations are typically carried out using separate tools, by persons with different roles, with different objectives. Silo effects can result, leading to slow development processes and suboptimal solutions.Purpose: This research is related to the realization of a framework that enables the concurrent optimization of worker well-being and productivity. The framework demonstrates how digital human modeling can contribute to Ergonomics 4.0 and support a human factors centered approach in Industry 4.0. The framework also facilitates consideration of anthropometric diversity in the user group.Methods: Design and creation methodology was used to create a framework that was applied to a case study, formulated together with industry partners, to demonstrate the functionality of the noted framework.Results: The framework workflow has three parts: (1) Problem definition and creation of the optimization model; (2) Optimization process; and (3) Presentation and selection of results. The case study shows how the framework was used to find a workstation design optimized for both productivity and worker well-being for a diverse group of workers.Conclusions: The framework presented allows for multi-objective optimizations of both worker well-being and productivity and was successfully applied in a welding gun use case.
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| 12. |
- Iriondo Pascual, Aitor, 1993-, et al.
(author)
-
Using time-based musculoskeletal risk assessment methods to assess worker well-being in optimizations in a welding station design
- 2022
-
In: Proceedings of the 7th International Digital Human Modeling Symposium (DHM 2022), August 29–30, 2022, Iowa City, Iowa, USA. - : University of Iowa Press. - 9780984037841 ; , s. 1-13
-
Conference paper (peer-reviewed)abstract
- Simulation using virtual models is used widely in industries because it enables efficient creation, testing, and optimization of the design of products and production systems in virtual worlds. Simulation is also used in the design of workstations to assess worker well-being by using digital human modeling (DHM) tools. DHM tools typically include musculoskeletal risk assessment methods, such as RULA, REBA, OWAS, and NIOSH Lifting Equation, that can be used to study, analyze, and evaluate the risk of work-related musculoskeletal disorders of different design solutions in a proactive manner. However, most musculoskeletal risk assessment methods implemented in DHM tools are in essence made to assess static instances only. Also, the methods are typically made to support manual observations of the work rather than by algorithms in a software. This means that, when simulating full work sequences to evaluate manikins’ well-being, using these methods become problematic in terms of the legitimacy of the evaluation results. In addition to that, to consider objectives in optimizations, they should be measurable with real numbers, which most of musculoskeletal risk assessment methods cannot provide when simulating full work sequences.In this study, we implemented the musculoskeletal risk assessment method OWAS in a digital tool connected to the DHM tool IPS IMMA. We applied the Lundqvist index on top of the OWAS whole body risk category score. This gave us an integer of the time-based ergonomic load for a specific simulation sequence, enabling us to qualitatively compare different design solutions. Using this approach, we performed an optimization in a welding gun workstation to improve the design of the workstation. The results show that using time-based musculoskeletal risk assessment methods as objective functions in optimizations in DHM tools can provide valuable decision support in finding solutions for workstation designs that consider worker well-being.
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| 13. |
- Keyvani, Ali, et al.
(author)
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Ergonomic Risk Assessment of a Manikin’s Wrist Movements - a Test Study in Manual Assembly
- 2013
-
Conference paper (peer-reviewed)abstract
- Use of digital human modeling (DHM) tools enables early assessment of ergonomic risks in the production development process. This early risk assessment can indicate needs for preventive actions in order to decrease risks for work-related musculoskeletal disorders. A method for the assessment of physical workload has been developed, for the analysis of wrist joint data produced by a DHM tool. The method is tested in a simulation model of an actual manual assembly station in industry where it is assumed that physical workload problems exist. The results show that the method can be successfully applied on an industrial case. In addition, presumptive risks and possible diagnoses are predicted based on the similarity of the simulated task’s motions with motions from other known work class profiles stored in a database based on epidemiological research.
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| 14. |
- Lind, Andreas, 1985-, et al.
(author)
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Digital support for rules and regulations when planning and designing factory layouts
- 2023
-
In: Procedia CIRP. - : Elsevier. - 2212-8271 .- 2212-8271. ; 120, s. 1445-1450
-
Journal article (peer-reviewed)abstract
- Factory layouts are frequently planned and designed in virtual environments, based on the experience of the layout planner. This planning and design process depends on information from several cross-disciplinary activities performed by several functions and experts, e.g., product development, manufacturing process planning, resource descriptions, ergonomics, and safety. Additionally, the layout planner also needs to consider applicable rules and regulations. This experience-based and manual approach to plan and design factory layouts, considering a multitude of inputs and parameters, is a cumbersome iterative process with a high risk of human error and faulty inputs and updates. The general trend in industry is to automate and assist users with their tasks and activities, deriving from concepts such as Industry 4.0 and Industry 5.0. This paper presents and demonstrates how digital support for rules and regulations can assist layout planners in factory layout work. The objective is to support the layout planner in accounting for area/volume reservations required to comply with rules and regulations for workers and equipment in the factory layout. This is a step in a wider initiative to provide enhanced digital support to layout planners, making the layout planning and design process more objective and efficient, and bridge gaps between cross-disciplinary planning and design activities.
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| 15. |
- Lind, Andreas, 1985-, et al.
(author)
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Evaluating a Digital Twin Concept for an Automatic Up-to-Date Factory Layout Setup
- 2022
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In: SPS2022. - Amsterdam; Berlin; Washington, DC : IOS Press. - 9781643682686 - 9781643682693 ; , s. 473-484
-
Conference paper (peer-reviewed)abstract
- Today, manufacturing factory layout setups are most often manually designed and kept up-to-date during their lifecycle with computer-aided design software’s, so that analyses, verification simulations, and decisions can continuously be done. This manual approach is a cumbersome iterative process to collect the necessary information, with a high risk of faulty inputs and updates. Often the virtual descriptions do not match the physical version of the factory setup. This research presents a digital twin solution where physical equipment is connected to a virtual representation of the same equipment and automatically updates the virtual environment with the spatial position of the physical equipment and a proposed way to evaluate it. The physical equipment either has inbuilt sensors or has been equipped with external wireless sensors to track the spatial position. The metadata are distributed via Node-RED (a tool to visualize Internet of Things) to the simulation software Industrial Path Solutions, where the virtual equipment is repositioned based on data from the physical equipment. The result shows that it is possible to send spatial position information from a physical equipment and update the corresponding virtual description of the equipment in its virtual environment. The accuracy of the updates has been evaluated with manual measurements. Hence, the virtual environment of the factory setup, i.e., the digital twin, updates automatically based on the data sent by the physical equipment. With an up-to-date virtual environment, more accurate simulations and optimizations of the factory setup can be achieved. Examples of such possibilities are to evaluate ergonomic conditions or to optimize robot paths for robot cells in realistic and up-to-date virtual environments. Also, one could imagine making virtual reality visits to hazardous or sensitive factory environments in a safe way or studying things that otherwise would be hard or impossible in the real world.
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| 16. |
- Lind, Andreas, 1985-, et al.
(author)
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Extending and demonstrating an engineering communication framework utilising the digital twin concept in a context of factory layouts
- 2023
-
In: International Journal of Services Operations and Informatics. - : InderScience Publishers. - 1741-539X .- 1741-5403. ; 12:3, s. 201-224
-
Journal article (peer-reviewed)abstract
- The factory layout is frequently planned in virtual environments, based on the experience of software tool users. This planning process is cumbersome and iterative to collect the necessary information, with a high risk of faulty inputs and updates. The digital twin concept has been introduced in order to speed up information sharing within a company; it relies on connectivity. However, the concept is often misunderstood as just a 3D model of a virtual object, not including connectivity. The aim of this paper is to present an extended virtual and physical engineering communication framework including four concepts: digital model, digital pre-runner, digital shadow, and digital twin. The four concepts are demonstrated and described in order to facilitate understanding how data exchange between virtual and physical objects can work in the future and having up-to date virtual environments enables simulating, analysing, and improving on more realistic and accurate datasets.
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| 17. |
- Lind, Andreas, 1985-, et al.
(author)
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Multi-objective optimisation of a logistics area in the context of factory layout planning
- 2024
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In: Production & Manufacturing Research. - : Taylor & Francis Group. - 2169-3277. ; 12:1
-
Journal article (peer-reviewed)abstract
- The manufacturing factory layout planning process is commonly supported by the use of digital tools, enabling creation and testing of potential layouts before being realised in the real world. The process relies on engineers’ experience and inputs from several cross-disciplinary functions, meaning that it is subjective, iterative and prone to errors and delays. To address this issue, new tools and methods are needed to make the planning process more objective, efficient and able to consider multiple objectives simultaneously. This work suggests and demonstrates a simulation-based multi-objective optimisation approach that assists the generation and assessment of factory layout proposals, where objectives and constraints related to safety regulations, workers’ well-being and walking distance are considered simultaneously. The paper illustrates how layout planning for a logistics area can become a cross-disciplinary and transparent activity, while being automated to a higher degree, providing objective results to facilitate informed decision-making.
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| 18. |
- Lind, Andreas, 1985-, et al.
(author)
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Multi-Objective Optimization of an Assembly Layout Using Nature-Inspired Algorithms and a Digital Human Modeling Tool
- 2024
-
In: IISE Transactions on Occupational Ergonomics and Human Factors. - : Taylor & Francis Group. - 2472-5838 .- 2472-5846.
-
Journal article (peer-reviewed)abstract
- OCCUPATIONAL APPLICATIONSIn the context of Industry 5.0, our study advances manufacturing factory layout planning by integrating multi-objective optimization with nature-inspired algorithms and a digital human modeling tool. This approach aims to overcome the limitations of traditional planning methods, which often rely on engineers’ expertise and inputs from various functions in a company, leading to slow processes and risk of human errors. By focusing the multi-objective optimization on three primary targets, our methodology promotes objective and efficient layout planning, simultaneously considering worker well-being and system performance efficiency. Illustrated through a pedal car assembly station layout case, we demonstrate how layout planning can transition into a transparent, cross-disciplinary, and automated activity. This methodology provides multi-objective decision support, showcasing a significant step forward in manufacturing factory layout design practices.TECHNICAL ABSTRACTRationale: Integrating multi-objective optimization in manufacturing layout planning addresses simultaneous considerations of productivity, worker well-being, and space efficiency, moving beyond traditional, expert-reliant methods that often overlook critical design aspects. Leveraging nature-inspired algorithms and a digital human modeling tool, this study advances a holistic, automated design process in line with Industry 5.0. Purpose: This research demonstrates an innovative approach to manufacturing layout optimization that simultaneously considers worker well-being and system performance. Utilizing the Non-dominated Sorting Genetic Algorithm II (NSGA-II) and Particle Swarm Optimization (PSO) alongside a Digital Human Modeling (DHM) tool, the study proposes layouts that equally prioritize ergonomic factors, productivity, and area utilization. Methods: Through a pedal car assembly station case, the study illustrates the transition of layout planning into a transparent, cross-disciplinary, and automated process. This method offers objective decision support, balancing diverse objectives concurrently. Results: The optimization results obtained from the NSGA-II and PSO algorithms represent feasible non-dominated solutions of layout proposals, with the NSGA-II algorithm finding a solution superior in all objectives compared to the expert engineer-designed start solution for the layout. This demonstrates the presented method’s capacity to refine layout planning practices significantly. Conclusions: The study validates the effectiveness of combining multi-objective optimization with digital human modeling in manufacturing layout planning, aligning with Industry 5.0’s emphasis on human-centric processes. It proves that operational efficiency and worker well-being can be simultaneously considered and presents future potential manufacturing design advancements. This approach underscores the necessity of multi-objective consideration for optimal layout achievement, marking a progressive step in meeting modern manufacturing’s complex demands.
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| 19. |
- Lind, Andreas, 1985-, et al.
(author)
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Multi-Objective Optimization of Assembly Manufacturing Factory Setups
- 2021
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In: 37th International Manufacturing Conference. - : The Irish Manufacturing Council (IMC). ; , s. 486-498
-
Conference paper (peer-reviewed)abstract
- Factory setup lifecycles are most often described and prepared manually in CAD environments, based on experience and inputs from several cross-disciplinary processes. Early in the factory setup preparation, a so-called block layout is created. The intention is to describe a high-level view of the intended factory setup and to claim area reservations and allocations. Factory areas are then blocked, i.e., targeted to be used for specific intended resources and processes, later redefined with detailed factory setup layouts.This research presents an automated digital method for assembly manufacturing layout planning, where area utilization and ergonomics can be considered simultaneously in a cross-disciplinary manner. Input datasets are company-specific descriptions of required dimensions for specific area reservations, such as defined dimensions of operator workspace, material façades, aisles, and the sequence to realize the product assembly manufacturing process.To test and develop the digital method, a demonstrator has been developed with adaptation of existing software that simulates and proposes optimized designs of detailed layouts. The method considers productivity, ergonomics, area utilization, and constraints, with a multi-objective optimization approach.In the demonstrator, the input data are sent to the simulation software IPS (Industrial Path Solutions). Based on the input and Lua scripts, the IPS software generates a block layout in compliance with the company’s defined dimensions of area reservations. Communication is then established between the IPS and the software EPP (Ergonomics in Productivity Platform), including intended resource descriptions, assembly manufacturing process, and manikin (digital human) resources. Using multi-objective optimization approaches, the EPP software then calculates layout proposals that are sent iteratively and simulated and rendered in IPS, following rules and regulations defined in the block layout as well as productivity and ergonomics constraints objectives.The developed demonstrator is promising and can optimize multiple parameters and weight the parameters to fine tune the optimal result of the detailed layout. The intention of the demonstrator is to make the preparation cross-disciplinary, transparent and achieve a common preparation of the assembly manufacturing factory setup, thereby facilitating better decisions.
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| 20. |
- Lind, Andreas, 1985-, et al.
(author)
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Virtual-Simulation-Based Multi-Objective Optimization of an Assembly Station in a Battery Production Factory
- 2023
-
In: Systems. - : MDPI. - 2079-8954. ; 11:8
-
Journal article (peer-reviewed)abstract
- The planning and design process of manufacturing factory layouts is commonly performed using digital tools, enabling engineers to define and test proposals in virtual environments before implementing them physically. However, this approach often relies on the experience of the engineers involved and input from various cross-disciplinary functions, leading to a time-consuming and subjective process with a high risk of human error. To address these challenges, new tools and methods are needed. The Industry 5.0 initiative aims to further automate and assist human tasks, reinforcing the human-centric perspective when making decisions that influence production environments and working conditions. This includes improving the layout planning process by making it more objective, efficient, and capable of considering multiple objectives simultaneously. This research presents a demonstrator solution for layout planning using digital support, incorporating a virtual multi-objective optimization approach to consider safety regulations, area boundaries, workers’ well-being, and walking distance. The demonstrator provides a cross-disciplinary and transparent approach to layout planning for an assembly station in the context of battery production. The demonstrator solution illustrates how layout planning can become a cross-disciplinary and transparent activity while being automated to a higher degree, providing results that support decision-making and balance cross-disciplinary requirements.
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| 21. |
- Mårdberg, Peter, et al.
(author)
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Using a formal high-level language and an automated manikin to automatically generate assembly instructions
- 2014
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In: International Journal of Human Factors Modelling and Simulation. - : InderScience Publishers. - 1742-5549. ; 4:3, s. 233-249
-
Journal article (peer-reviewed)abstract
- This paper presents an approach to automatically generate predetermined motion time system (PMTS) based assembly instruction lists from simulations within digital human modelling (DHM) software. A formal high-level instruction language is used to instruct an automated manikin to perform assembly operations. The manikin, the language and the assembled objects are composed into a discrete model. In a post-computational step, the model is used to construct PMTS instruction lists by mapping the manikin motions, assembled objects and the language instructions onto a set of PMTS keywords. The described approach is implemented in the DHM software IMMA and tested on industrial cases of manual assembly in the automotive industry.
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| 22. |
- Perez Luque, Estela, 1994-, et al.
(author)
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Motion Behavior and Range of Motion when Using Exoskeletons in Manual Assembly Tasks
- 2020
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In: SPS2020. - Amsterdam : IOS Press. - 9781643681467 - 9781643681474 ; , s. 217-228
-
Conference paper (peer-reviewed)abstract
- The manufacturing industry is becoming increasingly more complex as the paradigm of mass-production moves, via mass-customization, towards personalized production, and Industry 4.0. This increased complexity in the production system also makes everyday work for shop-floor operators more complex. To take advantage of this complexity, shop-floor operators need to be properly supported in order to perform their important work. The shop-floor operators in this future complex manufacturing industry, the Operator 4.0, need to be supported with the implementation of new cognitive automation solutions. These automation solutions, together with the innovativeness of new processes and organizations will increase the competitiveness of the manufacturing industry. This paper discusses three different aspects of production innovation in the context of the needs and preferences of information for Operator 4.0. Conclusively, product innovations can be applied in the manufacturing processes, and thus becoming process innovations, but the implementation of such innovations require organizational innovations.
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| 23. |
- Rhen, Ida-Märta, 1975, et al.
(author)
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Ergonomic risk assessment in DHM tools employing motion data : Exposure calculation and comparison to epidemiological reference data
- 2018
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In: International Journal of Human Factors Modelling and Simulation. - Olney : InderScience Publishers. - 1742-5549 .- 1742-5557. ; 6:1, s. 31-64
-
Journal article (peer-reviewed)abstract
- Digital human modelling (DHM) allows ergonomic risk assessment to be performed at early stages of design and development. Such assessment is typically based on observational methods, which do not take advantage of the potential of DHM tools to provide precise posture and motion data. This paper describes and illustrates an alternative assessment approach employing DHM tools, inspired by risk assessment based on direct measurements. A literature survey established a reference database of epidemiological associations between exposure and wrist-related disorders. This approach is illustrated by a DHM simulation of a car assembly task. Wrist posture and motion were simulated and compared to the database, predicting the prevalence of work-related musculoskeletal disorders on the basis of direct measurements.
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| 24. |
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| 25. |
- Rhen, Ida-Märta, et al.
(author)
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Time dependent exposure analysis and risk assessment of a manikin's wrist movements
- 2011
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In: Proceedings of DHM, First International Symposium on Digital Human Modeling. - : Université Claude Bernard Lyon. - 9782953951509
-
Conference paper (peer-reviewed)abstract
- The increased computerisation of design and engineering work has led to the development of software such as digital human modeling (DHM) tools. These tools can be used to simulate and visualise human work and for evaluating ergonomic conditions. Observational-based ergonomics methods, such as RULA and OWAS, may be used for characterizing workload and are typically integrated in DHM tools. However, using observational-based methods usually means that ergonomics evaluations are based on assessing static postures, i.e. not taking time-related aspects into account. This is usually also the case when industrial companies choose to customize the DHM software and integrate their own company specific ergonomics methods. Since time-sensitive aspects, such as frequency and angular velocity, are of importance in the ergonomics evaluation, it is necessary to be able to predict these variables also in an early stage of the design process. As observation methods are poor in terms of sensitivity they give rough estimations of ergonomic conditions. Consequently, researchers aim to develop dynamic evaluation methods where also time-dependent aspects, such as repetitiveness, velocity and duration in exposed positions, are considered. The objective of this study is to focus on the assessment of the wrist since a large amount of work related disorders is caused by this joint and also due to the fact that this is a relatively uncomplicated joint to explore from a biomechanical perspective. This paper displays initial findings from the literature for how to adequately and quantitatively assess wrist movements, appropriate evaluation criteria and for how to calculate cumulative load. Moreover, the paper illustrates how time significant wrist exposure data obtained from a DHM may be used for ergonomics assessment. This involves a proposed time consideration concept, based on a combination of modified and established evaluation methods, including suggestions for how to identify fundamental cycles.
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| 26. |
- Ayas, Ebru, 1977-
(author)
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Engineering Feelings of Quality
- 2008
-
Licentiate thesis (other academic/artistic)abstract
- There is an increasing emphasis on developing systematical research approaches for design of products that appeal to people’s emotions and values. This thesis proposes methodological developments for investigating people’s subjective emotional needs and values towards quality and explores interactions of related physical design attributes for product design.The overall aim of the licentiate thesis is to gain an understanding on Affective engineering of products through exploring the concept of quality feeling and to develop methodological approaches for this. Quality feeling can be described as a holistic concept considering individuals’ perceptions, expectations, experiences, physical and psychological expressions for a product or service. Affective Engineering methodology aims at translating human psychological processes, such as feelings and emotions, into appropriate product design attributes, such as size, shape, and surface characteristics.The thesis presents three methodological approaches when evaluating products for affective engineering and one approach for an interactive product design support system development.The first study presented deals with feelings of quality for reach truck operator’s cabin components. Components that would convey to give a higher total quality feeling were identified and improvement opportunities were prioritized. The second study presented is based on developing an interactive affective design and decision support system software for design of the steering wheel from drivers’ individual and shared preferences. In the third study affective values arising from judgments for important feelings of quality is the study basis. The author presents research on identifying interactions of design attributes for affective values in waiting areas of primary health care services.Further, a new approach for applying Affective Engineering in design of complex contexts is proposed.The proposed approach aims to handle contexts where feelings and design attributes have complex interactions for products and services that give almost an infinite number of design alternatives that are difficult to handle in traditional Kansei Engineering studies. With this thesis also an interactive product design and decision support system software is developed for steering wheel design and proposed for educational and industrial use. The proposed system works based on linking product design attributes to human feelings by applying Genetic algorithms and provides potential basis for future product development and improvements.This thesis has also contributed with affective design recommendations applicable for vehicle cabins and waiting areas in primary health care. Moreover, a number of existing methods in Affective Engineering have been tested and methodological experience is drawn, including advantages, disadvantages and limitations of using these methods.
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| 27. |
- Bergman, Christian, et al.
(author)
-
A Library Based Tool to Assist the Generative Activity in Workstation Design
- 2014
-
In: Advances in Ergonomics in Design, Usability & Special Populations. - : AHFE Conference. - 9781495121074 ; , s. 206-214
-
Conference paper (peer-reviewed)abstract
- Workstation design processes are seldom as rigorous as product design processes. Instead, workstations are often “just built”. This commonly results in workstations that suffer from problems related to ergonomics, flexibility, logistics, productivity etc., in turn leading to reductions in human wellbeing and/or economics. The problem is seldom a lack of information, about ergonomics or other relevant areas, in itself. The problem is rather knowledge of how to find, interpret and use the information proactively in the design of workstations, e.g. in the definition of a complete set of goals for a successful design, or in the generation of design solutions that fulfil these goals. Moreover, the evaluation of a workstation design is typically performed on actual workstations, or physical mock-ups representing near-completed proposals. This paper argues that workstation design processes could gain from utilizing product design methodologies. In line with this, a novel and structured way of establishing a library of verified design solutions that fulfil certain requirements is presented in this paper. This would help the designer to select and generate solutions for the design task at hand, thus speeding up the design process and reducing the risk of redesign and rebuild, due to not fulfilling set requirements.
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| 28. |
- Bergman, Christian, et al.
(author)
-
A tool to assist and evalute workstation design
- 2013
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In: Proceedings of NES 2013, 45th Nordic Ergonomics & Human Factors Society conference, Iceland, August 2013. - 9789979723974
-
Conference paper (peer-reviewed)abstract
- It can be argued that it is common that industrial workstations are “built” rather than purposefully designed with user and task requirements in mind. Afterwards, built-in problems typically need to be corrected, causing undesired costs and efforts. With the objective to assist workstation designers in avoiding most problems already in the design phase, a design support tool is being developed. The paper argues the need for such a tool and presents the fundamental tool functionality. Expected advantages are more efficient and ergonomic workstations and a more efficient design process with built-in learning and documentation.
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| 29. |
- Bergman, Christian, et al.
(author)
-
Implementation of Suitable Comfort Model for Posture and Motion Prediction in DHM Supported Vehicle Design
- 2015
-
In: Procedia Manufacturing. - : Elsevier. - 2351-9789. ; 3, s. 3753-3758
-
Journal article (peer-reviewed)abstract
- Driver-vehicle interaction analyses are done to ensure a successful vehicle design from an ergonomics perspective. Digital Human Modelling (DHM) tools are often used to support such verifications, particularly at early stages of the product development process. When verifying that a vehicle design accommodates the diversity of users and tasks, a DHM tool needs to be able to represent postures and motions that are likely under certain conditions. This functionality is essential so that the tool user will obtain objective and repeatable simulation results. The DHM tool IMMA (Intelligently Moving Manikins) predicts postures and motions by using computational methods. This offers the possibility to generate postures and motions that are unique for the present design conditions. IMMA was originally developed for simulating manual assembly work, whereas the work presented here is a step towards utilizing the IMMA tool for occupant packaging and related tasks. The objective is a tool for virtual verification of driver-vehicle interaction that supports and automates the simulation work to a high degree. The prediction functionality in IMMA is based on the use of optimization algorithms where one important component is the consideration of comfort level. This paper reports results from an basic investigation of driving postures and available comfort models suitable in a driving context, and shows initial results of seated posture and motion prediction functionality in the IMMA tool.
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| 30. |
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| 31. |
- Bertilsson, Erik, et al.
(author)
-
Assessment of manikin motions in IMMA
- 2012
-
In: Advances in applied human modeling and simulation. - Boca Raton : CRC Press. - 9781439870310 - 9781439870327 - 9780429061943 ; , s. 235-244
-
Book chapter (peer-reviewed)abstract
- When evaluating human-machine interaction in a virtual environment using Digital human modelling (DHM) it is important to ensure that the predicted motions lie within the range of behavioural diversity for different people within a population. This paper presents a study in which a comparison is made between motions predicted by the DHM tool IMMA (Intelligently Moving Manikin) and motions from real humans stored in a motion database. Results show similar motions but the predicted motions were in total statistically significantly different compared to the motions performed by real persons. The differences are most likely due to the balance function and joint constraints that the IMMA tool uses for predicting motions. Differences can also be due to other factors, aside of body size, such as age, gender or strength that affects the movement behaviour.
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| 32. |
- Bertilsson, Erik, et al.
(author)
-
Creation of the IMMA manikin with consideration of anthropometric diversity
- 2011
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In: 21st International Conference on Production Research: Innovation in Product and Production, ICPR 2011; Stuttgart; Germany; 31 July 2011 through 4 August 2011. - : Fraunhofer Verlag. - 9783839602935 - 3839602939
-
Conference paper (peer-reviewed)abstract
- Digital human modelling (DHM) systems are used to simulate production processes and analyse the human-machine interaction, particularly at early development stages. Consideration of anthropometric variation is central in DHM simulations due to the necessity of ensuring intended accommodation levels. This paper describes the process of how digital human models are created and defined within the IMMA software. The process begins with the definition of a number of key measurements, which acts as the basis for the definition of several boundary manikins using a confidence ellipsoid methodology. These manikins represents the appropriate confidence region and hence the anthropometric diversity. Key measurements are then entered into regression equations to define the complete set of measurements for each manikin. These measurements are based on the appropriate ISO-standard. Finally, measurements are used to define the size and alignment of each segment in the biomechanical model of the manikin. The manikins are then used to automatically simulate and analyse human-machine interaction.
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| 33. |
- Bertilsson, Erik, et al.
(author)
-
Digital Human Model Module and Work Process for Considering Anthropometric Diversity
- 2010
-
In: Proceedings of the 3rd Applied Human Factors and Ergonomics (AHFE) International Conference. - Louisville : AHFE International. - 9780979643545
-
Conference paper (peer-reviewed)abstract
- In digital human modelling (DHM), ergonomics evaluations are typically done with few human models. However, humans vary a lot in sizes and shapes. Therefore, few manikins can rarely ensure accommodation of an entire target population. Different approaches exist on how to consider anthropometric diversity. This paper reviews current DHM tools and clarify problems and opportunities when working with anthropometric diversity. The aim is to suggest functionality for a state of the art DHM module and work process for considering anthropometric diversity. The study is done by an analysis of some of the current DHM systems and by interviews of personnel at car companies about their way of working with anthropometric diversity. The study confirmed that critical production simulations are often done in early development stages with only one or a few human models. The reason for this is claimed to be time consuming processes, both at the creation of the human model but mainly when correctly positioning the model in the CAD environment. The development of a new method and work process for considering anthropometric diversity is suggested. Necessary features for such a module are that it shall be easy to use and not require expert knowledge about the consideration of anthropometric diversity. It shall also be configurable and transparent, in a sense that it should be possible to work with own anthropometric data and ergonomics evaluation standards. The module has to be flexible and have different entrances depending on the type of anthropometric problem being analyzed. An improved work method is expected to lead to faster and more correct analyses.
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| 34. |
- Bertilsson, Erik, et al.
(author)
-
Digital Human Model Module and Work Process for Considering Anthropometric Diversity
- 2011. - 1
-
In: Advances in Applied Digital Human Modeling. - Boca Raton : CRC Press. - 9781439835128 - 9781439835111 - 9780429151842 ; , s. 568-577
-
Book chapter (peer-reviewed)abstract
- In digital human modelling (DHM), ergonomics evaluations are typically done with few human models. However, humans vary a lot in sizes and shapes. Therefore, few manikins can rarely ensure accommodation of an entire target population. Different approaches exist on how to consider anthropometric diversity. This paper reviews current DHM tools and clarify problems and opportunities when working with anthropometric diversity. The aim is to suggest functionality for a state of the art DHM module and work process for considering anthropometric diversity. The study is done by an analysis of some of the current DHM systems and by interviews of personnel at car companies about their way of working with anthropometric diversity. The study confirmed that critical production simulations are often done in early development stages with only one or a few human models. The reason for this is claimed to be time consuming processes, both at the creation of the human model but mainly when correctly positioning the model in the CAD environment. The development of a new method and work process for considering anthropometric diversity is suggested. Necessary features for such a module are that it shall be easy to use and not require expert knowledge about the consideration of anthropometric diversity. It shall also be configurable and transparent, in a sense that it should be possible to work with own anthropometric data and ergonomics evaluation standards. The module has to be flexible and have different entrances depending on the type of anthropometric problem being analyzed. An improved work method is expected to lead to faster and more correct analyses.
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| 35. |
- Bertilsson, Erik, et al.
(author)
-
Multidimensional consideration of anthropometric diversity
- 2011
-
In: Proceedings of DHM, First International Symposium on Digital Human Modeling. - : Université Claude Bernard Lyon. - 9782953951509 ; , s. 1-6
-
Conference paper (peer-reviewed)abstract
- Boundary manikins, the concept of creating statistically extreme cases to accommodate a big part of the less extreme population has been known for decades. Despite this, many ergonomics simulations are done with few human models. This fact can be explained by the time consuming processes when working with many manikins in current digital human modelling (DHM) tools, but may also be a result of difficulty to understand how these manikins are calculated and defined. This paper focuses on the method of defining boundary manikins and how that functionality can be integrated into a DHM tool. Examples of boundary case methods in the literature often use Principal Component Analysis (PCA) which makes it possible to reduce the dimensions of the problem without much loss of the variance of the analysed data. Using PCA often demands some extent of manual analysis at the critical stage of reducing dimensions. This paper will explain a similar methodology for ceating boundary manikins from any number of variables, i.e. anthropometric variables chosen as key measurements. This method of creating a group of manikins is intended to be used in an automatic simulation feature in the IMMA software being developed in the associated research project. By using the method, a confidence region in the standardized space is created from eigenvectors and scaled eigenvalues of a correlation matrix. Boundary manikins are chosen at the ends of the axes of the enclosing confidence region, and one manikin of mean values is also added to the group of manikins. In the method presented here, the number of manikins created depends directly on the number of variables, which lead to the fact that the decision making of which key measurements to consider has to be done carefully to not create an overwhelming number of manikins. In comparison with one method using PCA, the method presented in this paper creates more manikins with a bigger difference in the max and min values of the chosen key measurements. If a limited number of cases are of crucial interest, then using PCA to reduce the dimensions of the problem is a good method to use. But if it is possible to create automated simulations the limitation of the number of manikins might not be so important. This will, though, depend heavily on the speed of the automated simulations.
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| 36. |
- Bertilsson, Erik, et al.
(author)
-
Swedish engineering anthropometric web resource
- 2011
-
In: Proceedings of NES2011 September 18—21, 2011 Oulu, Finland. - Oulu : University of Oulu. - 9789514295416 ; , s. 442-446
-
Conference paper (peer-reviewed)abstract
- Anthropometry, the study of human measurements, is central in the design of products and workplaces. This paper describes how Swedish anthropometric data is made available through a web page (www.antropometri.se) intended to be used by designers and engineers when developing new products and workplaces. With the anthropometric web resource it is possible to get mean and standard deviation values, and to calculate percentile values, for a number of anthropometric measurements. Further functionality on the web page enables simultaneous consideration of several anthropometric measurements. The web page also contains guidelines for how to use anthropometric data depending on the design task at hand.
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| 37. |
- Bertilsson, Erik, et al.
(author)
-
Use of digital human modelling and consideration of anthropometric diversity in Swedish industry
- 2010
-
In: Proceedings of the 42nd annual Nordic Ergonomic Society Conference. - 9788299574723
-
Conference paper (peer-reviewed)abstract
- This paper study and clarify problems, needs and opportunities when working with anthropometric diversity in digital human modelling (DHM) systems. A comparison between product development and production development in Swedish automotive industry is made. Interviews with DHM users and ergonomics specialists about their way of working with anthropometric diversity confirmed that simulations are often done with only one or a few human models. The reason for this is claimed to be time consuming processes, both at the creation of the human model but mainly when correctly positioning the model in the CAD environment.
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| 38. |
- Bertilsson, Erik, et al.
(author)
-
Using experimental design to define boundary manikins
- 2012
-
In: Work. - : IOS Press. - 1051-9815 .- 1875-9270. ; 41, s. 4598-4605
-
Journal article (peer-reviewed)abstract
- When evaluating human-machine interaction it is central to consider anthropometric diversity to ensure intended accommodation levels. A well-known method is the use of boundary cases where manikins with extreme but likely measurement combinations are derived by mathematical treatment of anthropometric data. The supposition by that method is that the use of these manikins will facilitate accommodation of the expected part of the total, less extreme, population. In literature sources there are differences in how many and in what way these manikins should be defined. A similar field to the boundary case method is the use of experimental design in where relationships between affecting factors of a process is studied by a systematic approach. This paper examines the possibilities to adopt methodology used in experimental design to define a group of manikins. Different experimental designs were adopted to be used together with a confidence region and its axes. The result from the study shows that it is possible to adapt the methodology of experimental design when creating groups of manikins. The size of these groups of manikins depends heavily on the number of key measurements but also on the type of chosen experimental design.
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| 39. |
- Billing, Erik, 1981-, et al.
(author)
-
Digital Human Modelling in Action
- 2019
-
In: Proceedings of the 15th SweCog Conference. - Skövde : University of Skövde. - 9789198366754 ; , s. 25-28
-
Conference paper (peer-reviewed)
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| 40. |
- Binkley, Dan, et al.
(author)
-
Tamm Review: Revisiting the influence of nitrogen deposition on Swedish forests
- 2016
-
In: Forest Ecology and Management. - : Elsevier BV. - 0378-1127 .- 1872-7042. ; 368, s. 222-239
-
Research review (peer-reviewed)abstract
- Are the health and productivity of Sweden's forests at risk from too much nitrogen (N) from acid deposition? Twenty years ago we assessed the evidence available for several aspects of this question (Binkley and Hogberg, 1997). We found little evidence for risks other than potential shifts in ground flora, but concerns continued to arise across Europe and elsewhere. We took advantage of two decades of accumulated evidence to re-evaluate whether Swedish forests are threatened by N deposition. During this time, N deposition declined by about 25% across the southern half of Sweden, and sulfur deposition declined by more than half. The growth rates of forests across the country continued the long-term trend of increasing by about 1-1.5% annually; average growth rates are now about 20-25% greater than in the mid-1990s. Forest soils often acidify by about 0.5-1.5 pH units during a rotation, but some evidence indicated that acidification may have occurred beyond this age-related pattern. Any average change in soil pH across the country appeared to relate more strongly to increases in carbon concentrations rather than cation leaching and declining base saturation. No evidence of N saturation (with outputs matching inputs) has been reported in Sweden, and nitrogen-limitation remains widespread. Fertilization with elements other than N generally does not increase growth unless N is also added, especially on mineral soils. Long-term fertilization experiments demonstrated that growth responses depended heavily on the dose rate of N application, not just cumulative totals. Repeated low rates of addition (20-50 kg N ha(-1) yr(-1)) provided greater growth increases per kg N added than higher rates, illustrating that the possible impacts of N deposition could not be reliably gauged by shorter-term experiments with unrealistically high dose rates. The composition of ground flora appeared to be sensitive to N additions, in studies across geographic gradients of N deposition and with high rates of N fertilization. Any long-term effects of N deposition on ground flora may be difficult to separate from long-term changes in stand structure and growth. Aluminum toxicity concerns do not appear to be supported by evidence, and liming generally does not increase forest growth. We discuss broader implications that arise from this assessment, including approaches to evaluating support for assumptions, the varying quality of types of evidence, and in some cases the irreducibility of uncertainty about elucidating cause-and-effect responses in complex forest systems.
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| 41. |
- Björkenstam, Staffan C, 1981, et al.
(author)
-
A framework for motion planning of digital humans using discrete mechanics and optimal control
- 2017
-
In: Proceedings of the 5th International Digital Human Modeling Symposium. - : Federal Institute for Occupational Safety and Health. ; , s. 64-71
-
Conference paper (peer-reviewed)abstract
- In this paper we present a framework for digital human modelling using discrete mechanics and optimal control. Discrete mechanics is particularly well suited for modelling the dynamics of constrained mechanical systems, which is almost always the case when considering complex human models interacting with the environment. We demonstrate that, by using recently developed recursive dynamics algorithms, we are able to efficiently use discrete mechanics in direct optimal control methods to plan for complex motions. Besides a proper mechanical model, an appropriate objective function is paramount to achieve realistic motions as a solution to an optimal control problem. Hence, several different objective functions, such as for example minimum time or minimum applied torque over the joints, are compared, and the resulting motions are analyzed and evaluated. To further improve the model, we include basic muscular models for the muscles of the shoulder, arm and wrist, and examine how this affects the motions.
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| 42. |
- Blomé, Mikael, et al.
(author)
-
Computer-based protocol for human simulation report
- 2003
-
In: Proceedings of IEA 2003. ; 3, s. 30-33
-
Conference paper (peer-reviewed)abstract
- The aim of the present case study is to present and evaluate a computer-based standardized procedure to order, perform and document virtual ergonomic analyses. Results showed that the use of the new working methodology increased the number of factors considered during analysis. Participants indicated that the proposed methodology, including task analysis and use of manikin families, would increase the reliability of the results. The increase in numbers of factors considered during analysis and the improved reliability of the results is also likely to reduce the number of iterations needed in the design process to make products meet established requirements, therefore reducing total development time.
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| 43. |
- Blomé, Mikael, et al.
(author)
-
Simulation of human-vehicle interaction in vehicle design at Saab Automobile : present and future
- 2003
-
In: Digital Human Modeling for Design and Engineering (DHM) SAE-conference. - 400 Commonwealth Drive, Warrendale, PA, United States : SAE International. ; 112:7, s. 644-650
-
Conference paper (peer-reviewed)abstract
- Developers, reviewers and users of human simulation tools claim that the use of these tools may reduce development time and development cost. However, before these benefits will be fully visible, there are some barriers to overcome. The aims of this case study are to identify which departments at Saab Automobile use some sort of human simulation tool today, and to identify the information flow and procedure when the tool is used. Four departments crash safety, packaging, production planning and vehicle ergonomics were identified as direct users of human simulation tools. The tools used were finite element with crash dummy representation, SAE human model, Safework and Ramsis. Communications between human simulation tool users are limited. Communications are done through the project management. The crash safety and packaging departments have formal descriptions of the human simulation process, whereas production planning and vehicle ergonomics have no formal process descriptions. To gain from the benefits of human simulation tools, Saab Automobile needs to adapt them to the organization and the organization to the tools. Integration of a working methodology is essential for effective and efficient use in the other human simulation departments where this is currently lacking.
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| 44. |
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| 45. |
- Bohlin, R., et al.
(author)
-
Automatic creation of virtual manikin motions maximizing comfort in manual assembly processes
- 2012
-
In: Technologies and Systems for Assembly Quality, Productivity and Customization. - : Conference on Assembly Technologies & Systems (CIRP). - 9780615640228 ; , s. 209-212
-
Conference paper (peer-reviewed)abstract
- Effective simulation of manual assembly operations considering ergonomic load and clearance demands requires detailed modeling of human body kinematics and motions, as well as a tight coupling to powerful algorithms for collision-free path planning. The focus in this paper is a unified solution that automatically creates assembly motions for manikins taking kinematic constraints, balance, contact forces, collision avoidance and comfort into account. The manikin used in this work has 162 degrees of freedom - six exterior fictitious joints determine the position of the lower lumbar and the remaining ones are interior joints. The inverse kinematic problem leads to an underdetermined system allowing us to pick a solution that maximizes a scalar valued comfort function. The comfort function offers a generic way to give preference to certain poses while avoiding others, typically by considering joint limits, forces and moments on joints, and magnitude of contact forces. In order to avoid collisions, poses close to collision are penalized. The method is implemented and demonstrated on two challenging assembly operations taken from the automotive industry.
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| 46. |
- Bohlin, Robert, et al.
(author)
-
Unified solution of manikin physics and positioning - Exterior root by introduction of extra parameters
- 2011
-
In: Proceedings of DHM, First International Symposium on Digital Human Modeling. - : Université Claude Bernard Lyon. - 9782953951509
-
Conference paper (peer-reviewed)abstract
- Simulating manual assembly operations considering ergonomic load and clearance demands requires detailed modeling of human body kinematics and motions, as well as a tight coupling to powerful algorithms for collision-free path planning. The focus in this paper is kinematics including balance and contact forces, and ergonomically preferable motions in free space. A typical manikin has more than 100 degrees of freedom. To describe operations and facilitate motion generation, the manikin is equipped with coordinate frames attached to end-effectors like hands and feet. The inverse kinematic problem is to find joint values such that the position and orientation of hands and feet matches certain target frames during an assembly motion. This inverse problem leads to an underdetermined system of equations since the number of joints exceeds the end-effectors' constraints. Due to this redundancy there exist a set of solutions, allowing us to consider ergonomics aspects and maximizing comfort when choosing one solution.The most common approach to handle both forward and inverse kinematics is building a hierarchy of joints and links where one root must be defined. A popular place to define the root is in a body part, e.g. in a foot. This leads to a two-step procedure; (i) one level determining when to re-root when moving the root part, (ii) then the Penrose pseudoinverse is used to match the end-effectors' constraints.In this paper we propose using a fixed exterior root by introducing six additional parameters positioning the lower lumbar - three rotations and three translations. This makes it possible to reposition the manikin without a series of re-rooting operations. Another important aspect is to keep the manikin, affected by internal and external forces and moments, in balance. However, by utilizing the exterior root and its added degrees of freedom it is possible to solve the balance, positioning, contact force and comfort problems simultaneously in a unified way. A manikin was implemented, and two test cases demonstrate the applicability of the presented method.
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| 47. |
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| 48. |
- Brolin, Anna, et al.
(author)
-
Kitting as an information source in manual assembly
- 2012
-
In: Advances in Ergonomics in Manufacturing. - : CRC Press. - 9781439870396 - 9780429107603 - 143987039X ; , s. 346-353
-
Book chapter (peer-reviewed)abstract
- In manual assembly, a strategy to meet the goal of efficient production is the increased use of kitting as a material supply principle. Even though kitting is already implemented in industry, there are still uncertainties regarding the effects of introducing kits, particularly from a human factors perspective.This paper presents initial steps in the development of a method to be used for the evaluation of kitting. This from an information source point of view and for studying effects related to productivity and quality. The methodology is projected to act as a foundation for how to carry out a subsequent comprehensive case study. The purpose of the case study is to explore how kitting affects the cognitive workload compared to the ordinary material rack combined with part numbers used in the current manufacturing industry. This is done by measuring productivity; time spent on assembling a product, and quality; number of assembly errors. One step in the methodology development process, which is described in this paper, was to conduct a pilot study, primarily to test the methodology related to the selection of measurement parameters, as well as for getting experiences from running the methodology with real test subjects.
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| 49. |
- Brolin, Anna, et al.
(author)
-
Second cycle education program in virtual ergonomics and design
- 2018
-
In: Proceedings of the 20th Congress of the International Ergonomics Association (IEA 2018). - Cham : Springer. - 9783319960708 - 9783319960715 ; , s. 1058-1065
-
Conference paper (peer-reviewed)abstract
- Current product and production development tends to become more complex where principal design decisions are made in very early development phases when product data only exist in virtual formats. To support this virtual product realisation process there exist a number of tools and technologies. Considering ergonomics and human factors in an increasingly complex process with often complex tools requires competent people able to handle multidisciplinary development challenges in a proactive manner. To answer the need for educational programs to cover these issues the School of Engineering Science at University of Skövde has developed a new master (second cycle) program Virtual Ergonomics and Design. The aim with the program is to give students and future product and production developers, necessary knowledge and skills to effectively use virtual tools for analysis, development, and verification of ergonomics and integrate ergonomics and user aspects into the product realisation process. This is achieved through a number of courses that partly forms a core within the subject Virtual product realisation but also provides in-depth knowledge in ergonomics. Students will in a possible future role as design or production engineers have a great influence on ergonomics in manufacturing departments but also better perception of ergonomics, higher motivation and knowledge of support tools and methods for ergonomics integration.
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| 50. |
- Brolin, Anna, et al.
(author)
-
Use of kitting to ease assemblers' cognitive workload
- 2011
-
In: Proceedings of NES2011 September 18—21, 2011 Oulu, Finland. - : University of Oulu. - 9789514295416 ; , s. 77-82
-
Conference paper (peer-reviewed)abstract
- The higher level of product variation in the automotive industry leads to an increasing workload for the assembler that has to search, fetch and assemble all the variants. This puts high demands on the information that is given to the assembler to fulfil the assembly task. This paper describes the impact of information overload and sources, and their influence on the assembler. Through observations conducted in the Swedish automotive industry, the study has shown that the assembly personnel perceive the kit as structured information and that structured kits are able to present distinct information at a certain place to the assembler, which in turn reduces the searching, resulting in decreased cognitive workload.
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