Advanced Materials Research Vol. 769

Abstract: Industrial enterprises are increasingly driven to tap the potentials of energy efficiency in existing and future production sites. The challenge is to identify cost-efficient levers for a low energy demand in the linked energy system of production machines and peripheral devices. Considering enabling technologies for energy efficiency and energy recovery in a cascaded energy network with energy storages this paper presents an approach towards energy and cost-efficient system configurations for production sites. An outlook will be given on the research center eta-factory for energy efficient factories at the PTW, TU Darmstadt.

Abstract: The judgment of global production networks is facing three major challenges. The complexity, measurable through the huge solution space, as well as the time-consuming preparation of a decision in line with the limited amount of time of the final decision makers – CEOs and upper management. The experience from several industry projects showed the demand to transfer and apply the concept of gamification in a cyber-physical environment to decision-making in Global Footprint Design. Smart IT tools, which support the intuition and practical knowledge of the decision maker but do not finally make the decision for them, are needed. Based on general criteria for successful gamified IT tools three specific requirements for judging global production networks are derived: value creation, ludic goal orientation and autonomous discovery. The major challenges and these specified principles of gamification are addressed within the scope of an IT tool which simplifies and improves complex global footprint decisions by employing elements of gamification. It is analysed to which degree the criteria are already fulfilled, which benefits this prototype of a gamified IT tool can offer and what future research has to be conducted in order to fully let CEOs game their global footprint strategy.

Abstract: Models to assess the maturity of a technology are commonly used in the aerospace sector. They give insights about technological risks and help to time the integration of new technologies to ensure their safe usage for society. Those models can also generate benefit for other sectors, such as the general mechanical engineering sector, when it comes to the assessment of new and complex technologies. Despite the big success of maturity models in the aerospace sector the usage of those models in general mechanical engineering lacks far behind its potential. Looking at actual trends as progressive globalisation and increasingly complex technology developments it will become more important to have a standard method for the maturity assessment of complex technologies. Especially for a small and medium-sized enterprise it is essential to have a clear understanding about the potentials and risks related to a new technology. One example of an upcoming technology for general mechanical engineering is the rise of carbon composite materials. They offer big potentials (e.g. light weight and excellent dynamic behaviour) on the one hand, but raise many technological and economic issues (e.g. missing connecting concepts as well as new process chains and costs) on the other. This article presents a method to assess the maturity of carbon composite components for their usage in general engineering applications. Different approaches for the maturity assessment of technologies were analysed. All concepts describe a technology’s maturity using multiple maturity phases. Those phases can either be passed in parallel or sequentially, which means that one phase has to be completed before the next phase can start. Further analysis showed that a technology’s maturity can best be described when stating not only the development risks but also the uncertainties about the future possible performance of a technology. With the described aspects in consideration the approaches were additionally adjusted to the special needs that arise when it comes to assessing materials: Manufacturing processes as well as component design are usually affected by material substitution. This applies in particular for carbon composites, because manufacturing processes and product design play a very important role for the final material characteristics and component performance. In collaboration with technology users, typical components with a generic character for general mechanical engineering applications were defined. To assess the technological maturity of those components the actual state of knowledge in the different necessary disciplines (e.g. conceptual design, dimensioning and computation methods, manufacturing techniques etc.) was consolidated. The research resulted in the creation of a concept to assess the maturity of material technologies in seven parallel phases. Those phases can be visualized as a maturity profile and two indicators can be derived, one indicating the uncertainty about the technology’s real capabilities, the other indicating the risks concerning the efforts necessary to actually develop the technology. Based on this concept a generic method was developed to assess a certain type of carbon composite component, where the specific requirements (e.g. forces, connecting joints, chemical resistance etc.) can be set individually. Those requirements are linked to the actual state of knowledge and define the level of completion in the different maturity phases, thus leading to the actual maturity profile and indicating the risks and uncertainties, which come along with the required carbon composite component. The results show significant differences in the maturity profiles of the different carbon composite components even though the material is the same. This implies that materials cannot be evaluated solely, because the interdependencies with manufacturing techniques and component design have to be taken into account.

Abstract: Industrial companies have to face fast changing markets and increasing customer demands regarding individual configuration of products. Within this turbulent environment initially defined planning circumstances and assumptions are no longer reliable over the whole factory life-cycle. As one approach to react on such uncertainties, flexible production planning is considered. Factories should be able to adapt according to changing demands and suit to even unforeseen constraints. To allow such flexibility, the factory planning process must be executed with special attention on the early phases. While setting up the key objectives and establishing the project basis, a focus on flexibility has to be mandatory. The constraints on which planning bear on need to be defined, but also their adaptation over the factory life-cycle must be considered. To overcome this dilemma of required level of detail but concurrent uncertain future estimations, scenario technique is proposed as a method in strategic company management. This paper deals with the extension of the scenario technique to be applicable during factory planning as one operative method in the early phases of ‘preparation’ and ‘structure planning’. By using immersive Virtual Reality (VR) tools, a visualization component will be added. This will make future scenarios more graspable for multi-domain planning teams and serve as a mean of communication on which decision making can be set up.

Abstract: Increasing demands on the flexibility of assembly workers lead to numerous times of high exposure rates within one shift. Inflexible processing times in synchronised assembly lines mismatch individual, circadian variable work capacities of operators. As a result, frequent performance peaks due to limited possibilities for individualisation elevate physiological and psychological workloads. The main objective of this paper is an individualisation of assembly system performance requirements. The conceptual framework presented gives the opportunity to specify diurnal assembly system performance requirements by recording and evaluating current processing times. The authors focus on the definition of demands on selecting a workstation, on raw data as well as on time measurement. Subsequently, a methodical approach to record current processing times as well as statistical data processing is presented. Moreover, the application of the presented method leads to an analysis of one representative workstation of a German car manufacturer’s engine assembly. Based on this, the authors define the production rhythm for this workstation and deduce statements on how to adapt the production system to current performance levels preventing physiological and psychological deterioration of assembly employees.

Abstract: The importance of knowledge workers and management staff in manufacturing companies is increasing due to a rising complexity within indirect business processes. As a result, current overhead costs account for most of the overall manufacturing costs. Despite this fact manufacturing companies disregard the productivity potentials of their indirect areas and focus predominantly on the optimisation of shop-floor processes.Cyber-physical systems constitute a technological paradigm of the current forth industrial revolution and promise a further push of labour productivity in the upcoming decades. We expand the vision of cyber-physical production systems on business processes and develop a mathematical approach to predict and analyse productivity potentials of management staff in the context of emerging cyber-physical production systems. The core element of the presented model states the collaborative productivity between people, people and smart devices and between these smart devices themselves.

Abstract: Nowadays, for customers the logistical performance of industrial companies is as important as the price and quality when buying decisions have to be made. It can be observed that considering the KPIs of logistical performance as quality figures, similar to the product quality, becomes quite popular within national and international markets. Two logistical performance key figures that can be pointed out in that context are short lead times and high schedule reliability. The delivery times demanded by markets often are shorter than the realizable lead times of products or the replenishment time of raw materials or purchased parts. In order to deliver the products in time, companies have the opportunity to implement so called order penetration point (OPP) within their productions. The OPP specifies the point within a production which connects upstream processes linked with work orders and downstream processes link with costumer orders. The OPP is often built up as a stock of unfinished goods. Currently companies position their OPP only with the goal to satisfy the demand of short lead times set by the market. Other logistical targets such as a low work-in-process (WIP), high schedule reliability or a high utilization are usually not taken into account. Hence, due to the complexity of positioning the OPP companies underestimate the logistical potentials that can be achieved by positioning the OPP optimally. In this publication the fundamental determining factors which both influence the position of the OPP and are influenced by the selected position of the OPP are presented. In particular the dependencies between the four logistical targets, lead time, WIP, schedule reliability and the grade of utilization, and the position of the OPP are discussed. Exemplarily the correlation between the position of OPP and the schedule adherence at the end of the supply chain are presented. It can be assumed that the schedule adherence increases by moving the OPP towards the end of the supply chain. Possible reasons that explain this particular effect, like the reduction of lead time variation, will be discussed in detail.