virtual maintenance simulation for socially sustainable serviceability

Abstract In order to achieve more sustainable development processes, industries need not only to improve energy efficiency and reduce costs, but also to increase the operators' wellbeing to promote social sustainability. In this context, the present research focuses on the definition of a methodology based on human-centred virtual simulation to improve the social sustainability of maintenance tasks by enhancing system design and improving its serviceability. It is based on the operators' involvement and the analysis of their needs from the early design stages on virtual mock-ups. The methodology proposed merges a protocol analysis for human factors assessment and an immersive virtual simulation where immersive serviceability simulations can be used during design phases. To demonstrate the effectiveness of the proposed method, an industrial use case has been carried out in collaboration with CNH Industrial

Проектирование электрических силовых установок при поддержке многоцелевыми стратегиями оптимизации

Electric drive systems consisting of battery, inverter, electric motor and gearbox are applied in hybridor purely electric vehicles. The layout process of such propulsion systems is performed on system level under consideration of various component properties and their interfering characteristics. In addition, different boundary conditions are taken under account, e. g. performance, efficiency, packaging, costs. In this way, the development process of the power train involves a broad range of influencing parameters and periphery conditions and thus represents a multi-dimensional optimization problem. Stateof-the-art development processes of mechatronic systems are usually executed according to the V-model, which represents a fundamental basis for handling the complex interactions of the different disciplines involved. In addition, stage-gate processes and spiral models are applied to deal with the high level of complexity during conception, design and testing. Involving a large number of technical and economic factors, these sequential, recursive processes may lead to suboptimal solutions since the system design processes do not sufficiently consider the complex relations between the different, partially conflicting domains. In this context, the present publication introduces an integrated multi-objective optimization strategy for the effective conception of electric propulsion systems, which involves a holistic consideration of all components and requirements in a multi-objective manner. The system design synthesis is based on component-specific Pareto-optimal designs to handle performance, efficiency, package and costs for given system requirements. The results are displayed as Pareto-fronts of electric power train system designs variants, from which decision makers are able to choose the best suitable solution. In this way, the presented system design approach for the development of electrically driven axles enables a multi-objective optimization considering efficiency, performance, costs and package. It is capable to reduce development time and to improve overall system quality at the same time.Системы электропривода, состоящие из аккумулятора, инвертора, электродвигателя и коробки передач, применяются в гибридных или чисто электрических транспортных средствах. Процесс компоновки таких движительных систем осуществляется на системном уровне с учетом различных свойств компонентов и их интерферирующих характеристик. Кроме того, учитываются разные граничные условия, например технические характеристики, эффективность, комплектование, стоимость. Таким образом, процесс разработки силовой передачи включает в себя широкий диапазон влияющих параметров и периферических условий и тем самым представляет собой проблему многомерной оптимизации. Современные процессы разработки мехатронных систем обычно выполняются в соответствии с V-моделью, которая представляет собой фундаментальную основу для управления сложными взаимодействиями различных дисциплин. Кроме того, применяются этапные процессы и спиральные модели, чтобы справиться с высоким уровнем сложности при разработке, проектировании и тестировании. Вовлекая большое количество технических и экономических факторов, эти последовательные рекурсивные процессы могут привести к неоптимальным решениям, поскольку процессы проектирования системы недостаточно учитывают сложные отношения между различными, частично конфликтующими областями. В этом контексте настоящая публикация представляет интегрированную многоцелевую стратегию оптимизации для эффективной концепции электрических силовых установок, включающую комплексное рассмотрение всех компонентов и требований на многоцелевой основе. Синтез системного дизайна основан на Парето-оптимальных конструкциях со специфическими компонентами с целью обеспечения работы, эффективности, комплектации и затрат, предусмотренных для данной системы. Результаты отображаются в виде Парето-фронтов вариантов систем электрических трансмиссий, из которых лица, принимающие решения, могут выбрать наиболее подходящее из них. Таким образом, представленный подход к проектированию системы для разработки осей с электрическим приводом обеспечивает многоцелевую оптимизацию с учетом эффективности, функционирования, стоимости и комплектации. Данный подход позволяет сократить время разработки и одновременно обеспечить улучшение качества системы

Modular Human-in-the-loop Design Framework Based on Human Factors

Human-in-the-loop design framework introduced in this dissertation utilizes Digital Human Modeling (DHM) to incorporate Human Factors Engineering (HFE) design principles early in design process. It embodies scientific methods (e.g., mathematics) and artistic approaches (e.g., visualization) to assess human well-being and overall system performance. This framework focuses not only on ergonomics assessments but also actual design process including, but not limited to, concept development, structural integrity and digital prototyping. It addresses to three major limitations found in HFE literature and practices

a mixed reality digital set up to support design for serviceability

Abstract Design for serviceability begins with understanding the customer needs related to availability, reliability, accessibility and visibility, and aims at designing optimized systems where maintenance operations are easy and intuitive in order to reduce the time to repair and service costs. However, service actions are difficult to predict in front of a traditional CAD model. In this context, digital manufacturing tools and virtual simulation technologies can be validly used to create mixed digital environments where service tasks can be simulated in advance to support product design and improve maintenance actions. Furthermore, the use of human monitoring sensors can be used to detect the stressful conditions and to optimize the human tasks. The paper proposes a mixed reality (MR) set-up where operators are digitalized and monitored to analyse both physical and cognitive ergonomics. It is useful to predict design criticalities and improve the global system design. An industrial case study has been developed in collaboration with CNH Industrial to demonstrate how the proposed set-up is used for design for serviceability, on the basis of experimental evidence

Achieving Customer Acceptance of Novel Product Features by Offering Customer Delight

Today’s markets often offer different product solutions to the same customer need. In particular, new products offer new features requiring new customer behavior. This is typically driven by technology push, environmental concerns, or legal requirements. Due to inconvenience users do not easily change their behavior and thereby reject novel products unless they offer an obvious delight in the eyes of the user. Product developers need to take this in account when designing products. Tools such as UX, Kansei Engineering and Kano model are amongst those supporting product practitioners. This is exemplified by the affective evaluation of computer mice over three generations. It can be seen that in particular women have different affective needs in comparison to men related to auditive properties of mice. Hence it is important to adjust the user panel composition in accordance with the expected effect in order to avoid biases due to lacking diversity

Design and Optimization of a FSAE Vehicle

This Major Qualifying Project (MQP) designed and manufactured a vehicle for the Formula SAE Michigan collegiate competition. The Formula SAE (FSAE) competition is a collegiate design series that challenges teams to conceive, design, and fabricate formula style vehicles that are validated through competition. The team built upon a vehicle intended for the 2012 FSAE competition. Baseline testing and evaluations identified the car’s rear suspension, packaging/ergonomics, continuously variable transmission, air intake, and exhaust as areas that could be improved. These components were redesigned and manufactured, improving the vehicle’s performance in static and dynamic competition events. All components were designed and validated using computer-aided modeling and simulation techniques

An objective measure to quantify discomfort in long duration driving

In recent years increased emphasis has been placed on improving seat comfort in automobiles. This is partly due to research showing that prolonged driving is associated with increased risk of musculoskeletal disorders, but largely because driver comfort is now viewed as an increasingly important aspect of the competitive marketing of vehicles. Driving is firmly cemented as a major part of most people s daily life across the world and people are now spending more time in their vehicles than ever before. As urban congestion continues to rise, commuting distances and durations will progressively increase, subjecting drivers to the risks of long duration driving more often. Consequently the automotive industry has invested in designing seats that perform better under increased usage durations and ergonomics has played a vital role in the design of new seats. However, the ability to design a successful seat relies heavily on the capacity to accurately evaluate the comfort of a vehicle seat and one major issue that has been highlighted with the current state of automotive ergonomics research is the standardisation of comfort evaluation techniques. This research aimed to tackle these issues by investigating the effects of long duration driving on discomfort and the range factors associated with driver discomfort. Furthermore, the ultimate goal of this research was develop and evaluate a novel objective measure of driver discomfort that focused on driver seat fidgets and movements (SFMs) with the aim of standardising discomfort evaluation within the automotive industry. Three laboratory studies and one field observation were conducted to address these aims whereby subjective and objective evaluations of discomfort were conducted during long term driving (ranging from 60 - 140 minutes). The results determined that a measure of driver SFMs can be effectively implemented into long duration driving trials to evaluate the effects of long term driving and vibration exposure on driver discomfort and subsequently used to make accurate predictions of overall discomfort. Large positive correlations have been determined between measures of SFMs and subjective ratings of overall discomfort (r2 > 0.9, P < 0.05) and the SFM method has been successfully repeated under a range of driving conditions. Driver seat fidget and movement (SFM) frequency is shown to significantly increase congruently with subjective ratings over the duration of a long term drive as drivers seek to cope with increased discomfort. It is proposed that drivers will record movements in the vehicle seat when discomfort reaches a threshold that is consciously or unconsciously perceived and as the duration of driving accrues, drivers will reach this threshold with increased frequency. A measure of both SFM frequency and total accumulative SFMs have been shown to accurately predict discomfort ratings and provides the basis for discomfort evaluations to be made via remote monitoring, removing the need for subjective assessment. During a long term drive, there becomes a point upon which improvements in seat design become ineffective as extended duration driving will result in discomfort regardless of how well the seat has been designed. It was shown that drivers will move in the vehicle seat to cope with increased discomfort and in addition, another method of combatting the negative effects of long term driving was investigated. Subjective and objective evaluation determined that breaks from driving will reduce discomfort both immediately and upon completion of a long term drive. Furthermore, these benefits were increased when drivers left the vehicle seat as discomfort was reset when drivers took a 10 minute walk. Walking during a break from driving can be considered the ultimate SFM. Drivers are recommended to plan breaks from driving when conducting a long duration journey in order to minimise discomfort and when taking a break, drivers should take a walk rather than remain seated in the vehicle