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For many years, the Association of German Engineers (VDI) has been issuing guidelines for simulating production and logistics systems as well as for Digital Factory tools. The target group encompasses experts from science, consulting institutions, industrial companies, interest groups and software houses. The guidelines represent the state of the art, but in individual cases can also be regarded as a preliminary stage of a standard. This opens up the possibility of publication without the topic already being viewed as capable of being standardized. An individual guideline can contain several guideline parts. In simulation software and Digital Factory tools, the working human is playing an increasing role. From this background, special guideline parts have already been published, which deal with the modeling of humans in production-logistic simulation and with ergonomic aspects in the Digital Factory. The last-mentioned guideline part deals with the work task and especially with related anthropometric and work-physiological aspects. A further guideline part is currently in the process of being published and regards the stresses and strains from the work environment. This guideline part with its close relation to Occupational Health and Safety is discussed in the following. It reveals that a large field of research and development issues still needs to be clarified in order to integrate these aspects into Digital Factory tools.

As a reaction to the volatile market demands with regards to the number and variants of products offered, ever more complex procedures for manufacturing control are being developed. Most recently, self-organising procedures, which often mimic the behaviour of natural systems, have arisen. The method of ant colony optimisation (ACO), which was inspired by ants, can provide the necessary fundamentals in order to realise self-organising manufacturing control. In this context, the ifab-Institute has developed the AntControl tool for self-organising manufacturing control based on ACO. In order to investigate the potential of ACO, several concepts have been developed and integrated into the existing OSim simulation tool to create the new OSim-Ant tool. An exemplary simulation study within a manufacturing system has been carried out to evaluate the behaviour of AntControl. This paper presents this tool as well as the results of the simulation study.

Due to the increasing competition in global markets, many European garment manufacturers have had to undergo significant restructuring and were forced to create leaner value-adding processes. As a result, the majority of the manufacturing operations have been outsourced to low labor cost countries. At the same time, production logistics as well as information and communication technologies have gained importance, in order to keep job functions requiring higher qualifications within Europe. Another challenge concerns the introduction of customized products into the production processes which previously had been designed for manufacturing of large volumes. Prior to implementing such changes, the consequences with respect to production logistics as well as the financial impacts should be examined. The case study presented in this paper uses a simulation tool for these purposes. Different scenarios developed for a garment company were analyzed. Based on the results, recommendations for the further development of the regarded company were deduced.

The examination of human performance within industrial processes increasingly extends beyond the matter of resource implementation. In addition to traditional approaches to personnel assignment planning, new management methods for the preservation and further development of personnel are becoming established. The following paper discusses the effects and challenges related to computed-aided competence management. For this purpose it is indispensable to examine the notion of competence more in depth as well as the resulting competence management. Since as of yet no universally valid definition of competence exists, the following article discusses various facets of competence management and illustrates these by considering individual simulation-aided decision and planning tools for industrial process optimization.

In the majority of manufacturing systems, human resources are the most expensive but also the most flexible factor. Therefore, the optimal utilization of human resources is an important success factor contributing to long-term competitiveness. In order to meet future requirements, which arise from continuous changes to products and technologies, production enterprises are forced to constantly adapt their human resources with respect to the number and abilities of employed persons. In order to accomplish this, it is necessary to define time frames, which allow for at least a rough planning of the needed number and abilities of a workforce. These time frames are determined by the dates when product or technology changes are expected. This already known technology calendar concept has now been enhanced by time frames for personnel development measures. Which worker is suitable for further education and how the respective abilities should be achieved is a subject matter related to the determination of qualitative personnel requirements, whereas the number of needed persons is a quantitative issue. If the required qualifications are to be available at the right point in time, it is indispensable that the necessary qualification measures are defined and scheduled appropriately. The concept, which has been developed here, describes the qualification measures, sorted into target groups, content, qualification costs and time. As a means to meet the personnel requirements arising from continuous changes to products and technologies, the enhanced technology calendar concept will be illustrated by using an application example.

The complexity of production management as well as manufacturing control has advanced exceptionally in the past years. In order to cope with the perpetually changing requirements, novel concepts and procedures have been developed. Since the beginning of the nineties, the trend is moving to self-organizing concepts of manufacturing control, like the holonic manufacturing. The Multi Ant Colony Systems, which are inspired by biological ants, can provide the necessary fundamentals in order to realise a holonic manufacturing control. This papers presents a procedure for the short-term, operative manufacturing control based on the Multi Ant Colony Systems.

The digital factory is becoming ever more prevalent in the planning of production systems. It provides tools that digitally support the planning process. Everything from a single workplace to a complete workshop or even a factory can be represented in the computer, analyzed for potential weaknesses and even revised digitally. In the field of occupational health and safety (OHS), this only affects ergonomic analyses and examinations of single workplaces at present. This micro-ergonomic approach is insufficient for extensive OHS measures because potential risks (e.g. noise) often result from the configuration of the whole work system and workers' change of workplaces during a shift. Therefore, a macro-ergonomic OHS evaluation approach which considers all elements of a work system and their interactions is also necessary. This paper describes a macro-ergonomic OHS approach to digital work systems planning developed at the ifab-Institute.

This paper presents a simulation aided approach for designing organizational structures in manufacturing systems. The approach is based on a detailed modeling and characterization of the forecasted order program, especially of elementary processes, activity networks and manufacturing orders. Under the use of the organization modeling system FORM, that has been developed at the ifab-Institute of Human and Industrial Engineering of the University of Karlsruhe, structuring strategies—e.g., a process-oriented strategy—can be applied in order to design organizational structures in manufacturing systems in a flexible and efficient way. Following that, a dynamical analysis of the created manufacturing structures can be carried out with the simulation tool FEMOS, that has also been developed at the ifab-Institute. The evaluation module of FEMOS enables to measure the designed solutions with the help of logistical—e.g., lead time degree—and organizational—e.g., degree of autonomy—key data. This evaluation is the basis for the identification of effective manufacturing systems and also of improvement potentialities. Finally, a case study is presented in this paper designing and analyzing different organizational structures of a manufacturing system where gear boxes and robot grip arms were manufactured.

In many manufacturing systems human resources are the most expensive, but also the most flexible factors. Therefore, the optimal utilization of human resources is an important success factor contributing to long-term competitiveness. With regard to the qualification of the workforce, there exist a large number of possibilities for varying the abilities of employed persons and for allocating them to tasks. Of course, the chosen assignment has an important effect upon labour cost and on the achievement of typical logistical goals. In order to consider the plurality of possibilities for personnel assignment and to exploit the flexibility of human resources, effective planning tools are needed. For this purpose, the ifab-Institute of Human and Industrial Engineering at the University of Karlsruhe exploits the possibility of using simulation as a planning tool, e.g. for re-assigning personnel to tasks in the middle term. Dependent upon the type of personnel assignment problem various tools have been developed, e.g. the personnel-oriented simulation tool ESPE (Engpassorientierte Simulation von Personalstrukturen). This article will explain, using one case study with varying questions, the procedures and the solutions for different types of personnel re-assignment problems.

Analogous to the well-known concept of product prototyping during the design phase of a new product, this paper discusses an approach for the prototyping of organisational structures of production systems. The procedure uses simulation techniques and is based on a special characterisation of the order processing. Specific process attributes are consulted for applying elementary structuring strategies, such as customer, order, product, task or process orientation. The procedure will be demonstrated through a case study of a company in the mechanical engineering area. With its help, a suitable departmental structure can be defined in order to integrate a new order type into the existing structure while increasing the performance of the entire production system.

During the realization of the CAESAR planning games, which has been supported by the European Leonardo da Vinci Programme, the use of modular planning games within a global scenario has shown to be very effective in concisely relaying educational content from the area of production management. In particular the close-to-reality situations have proven, time and again, to be highly motivating for seminar participants. In order to improve the transferability of acquired knowledge into practise, the ifab-Institute of Human and Industrial Engineering of the University of Karlsruhe has further developed the INSIGHTS-PPC planning game for production planning and control, in such a way that the planning tasks to be tackled are set in direct relation to market similar repercussions. This is realized in a new market share model. The market share model will be explained, paying particular attention to the practical consequences which come along with the implementation of such a model. Despite the potential of the de...

Many companies currently strive to support their employees' work-life balance through appropriate measures in order to improve employees' loyalty towards the company and to recruit new employees. In this context, flexibility in the area of working times is a measure that can influence employees' private lives immensely. This is why the individualisation of working time arrangements has been accorded high importance in current discussions on work-life balance. In this area, best practice examples can be found showing how working-time arrangements can improve the situation of the employees. It should be noted, however, that there is not one single perfect working-time model. A working-time model must always be adapted specifically to the actual situation of the company and the employees. Therefore, a targeted analysis of the challenges facing the company and the demands on the employees is essential for the creation of an appropriate working time policy. In particular, the employees' working-time preferences must be appropriately taken into account. Owing, however, to a combination of organisational complications and legal data protection restrictions, it is for the most part impossible to meet these working-time preferences in their entirety. This paper, which is based on an employee survey, illustrates the strain on employees in the retail sector and identifies different types of working-time preferences.

With regards to methods of assembly systems planning we are familiar with the depiction of the technical structure using capacity fields and graphs in addition to the modelling of assembly activities as a precedence diagram. However, no form of presentation has yet been defined that describes the assignment of staff within an assembly system. This paper discusses the concept of the staff assignment graph used to balance a hybrid assembly system, and in doing so marks a first attempt to close this gap and develop a more comprehensive planning method. The paper also explains how to evaluate staff assignment graphs and presents an algorithm for automatically generating them based on existing capacity graphs and taking a multi-criteria goal function into account.

Changes in international competition lead to changes of the requirements on production enterprises. The introduction of new production technologies does not seem to be exclusively an adequate reaction to the increasing problems. Therefore tools of computer-integrated production lCIMr and new organizational concepts have to be conceived. Because these organizational and technical means are linked on the one hand with severe changes in the production system and, on the other hand, with rather higher economic risks in their realization, the effects have to be estimated in advance in the planning stage. Consideration of dynamical system behaviour plays an important part because the main goal is the improvement of order processing. This paper presents a simulation program, which can be used during the design phase of the organizational structure of production systems as a powerful tool for predicting the effects of new computer-aided tools and structures.

Disassembly and recycling activities are becoming ever more important as a result of legislative changes. The disassembly of end of life products will come to have an increasingly industrial character focusing on the planning and control of economical disassembly processes. As a consequence, the pre-dominant form of work organisation will be based on the division of labour as this system allows for the efficient usage of various disassembly tools and methods in contrast to the complete-disassembly workstations mainly in use today. But the control strategies derived from assembly are only partially suitable for these disassembly systems as they do not sufficiently consider the specific characteristics of disassembly. Any control method suitable for this field of application needs to incorporate new approaches to the flexibilisation of workflows in disassembly systems.

In contrast to manufacturing and assembly systems, disassembly systems are marked by non-deterministic work sequences. The control of disassembly systems which adequately reacts to stochastically induced plan deviations are, therefore, of great importance for an efficient operation of disassembly systems. Thus, special control procedures, aligned to the requirements of disassembly, are required in order to manage disassembly systems appropriately. In order to improve disassembly control strategies, a simulation-aided control procedure for systems based on division of labour is under development to support the following tasks: Planning of the sequence of the disassembly orders, variation of the disassembly depth dependent upon the capacity utilization and variation of the disassembly operations according to the capacity utilization.

Current developments in Germany have led to severe consequences for the configuration of working times of medical and nursing personnel in hospitals. They underline the necessity to arrange work processes and person- nel employment as efficiently as possible. In this context, the current project "Process Optimization and Efficient Personnel Employment in Hospitals" has set the goal of developing a simulation-based procedure for the analysis of working time model. This procedure shall which can be used to explore the advantages and possibilities of working time models in hospitals based on simulation investigations and to derive configuration recommendations. The flexible alignment of the personnel capacity with the capacity requirements for patient treatment is used to achieve a high degree of patient-oriented service in medical tasks in order to help hospitals efficiently employ available personnel resources as well as to realize personnel-oriented goals. This article will intro- duce the developed concept for a simulation-based configuration of working times.

Currently, comprehensive tools are being developed which shall improve the process of factory planning. These tools are referred to as the “Digital Factory” and comprise diverse features, from capacity planning of production resources to visualisation and simulation of a virtual workshop. In a micro-ergonomic view, human-centred functionalities and ergonomic workplace design and assessment can also be included. From a macro-ergonomic point of view, however, the integration of personnel-oriented simulation is still missing. This paper describes the main functionalities of these features and hints at first pilot software for their integration into the Digital Factory.

The optimal utilisation of human resources is one of the most important success factors contributing to long-term competitiveness. An essential requirement for the optimal utilisation is a goal-oriented planning of personnel development. The principal intention of personnel development and assignment planning is to cope with technology and product changes. These changes not only demand a quick and flexible adaptation of machinery resources but also that of an existing workforce. In addition to the productions logistical and financial objectives, which are generally in the foreground during the implementation of new technologies and products, the workers’ personal concerns should be taken into account. In order to be able to offer a methodology for the continuous adaptation of a workforce to the process of change, the idea of the technology calendar concept is picked up and expanded here. Within this concept, the ifab-Institute of Human and Industrial Engineering at the University of Karlsruhe exploits the possibility of using simulation as a planning tool in order to support a goal-oriented planning of personnel development.

The configuration of a working time model is a very complex task due to the fact that different restrictions concerning work demands and employee preferences have to be taken into account. The use of a simulation tool is a promising approach as it allows for an objective, quantitative, efficient and prospective assessment of alternative working time models during the design phase. This paper presents a simulation study within a call-centre of manufacturer of electric devices.

This paper presents research activities associated with the development of a simulation tool for modelling human reliability in production systems. This dynamic model enables the planner to determine the consequences of changes in human reliability on the quality of the production processes and the products. The model is built upon the basis of a tool for human reliability analysis ESAT (Experten-System zur Aufgaben-Taxonomie; Aufgabentaxonomie: Ein Verfahren zur Ermittlung der menschlichen Leistung bei der Durchfuhrung von Aufgaben, Messerschmitt-Bolkow-Blohm, Ottobrunn, 1990.) and a personnel-oriented simulation programme ESPE (Engpassorientierte Simulation von Personalstrukturen; Ein engpassorientierter Ansatz zur simulationsunterstutzten Planung von Personalstrukturen, Dissertation, Karlsruhe University, 1994), developed at the ifab-Institute of Human and Industrial Engineering at the University of Karlsruhe. In addition to the definition and the calculation of the human error probabilities, the consequences of the human errors (i.e. rework and waste) for the quality of the processes and the products were also implemented. This method is able to systematically plan quality-oriented assignments of personnel to functions and workplaces (personnel structures) in production systems. The effectiveness of the method is demonstrated by a case study.

The short-lived nature of products requires production enterprises to plan new production systems in ever shorter intervals. The enterprises are thus prompted to improv their planning processes and in particular to shorten their planning times. Computer supported planning tools can be used to develop planning alternatives and to examine them, using simulation, with respect to their dynamic attributes. A substantial problem can be seen in the conception of a hybrid assembly system containing a similar amount of automated and manual stations. The procedure PAMELA was developed at the ifab-Institute of Human and Industhal Engineering at the University of Karlsruhe for the design of suitable planning solutions for hybrid assembly systems (Muller 2002; Zulch. Muller 200la).This procedure is based on the description of work content and the dependencies of assembly operations as well as several layered precedence diagrams. Simulation is called upon for the assessment and choice of alternative planning solutions. The use of the procedure PAMELA will be demonstrated in this article using an application example.

During a project in the frame of the European Leonardo-da-Vinci-Programme five simulation games have been developed in order to engage awareness of the participants for problems in real production processes. The games focus on different areas of the production environment and are based on a common scenario: the optimisation and redesign of a bicycle production. The simulation games have been played by both industrial managers and students and could succeed in team oriented education. Additionally, the completion of a book describing the games and including software versions of the used simulation tools enables self-training in the field of production management. In this paper the common scenario of the simulation games will be presented. Two selected simulation games will be arranged according to a game classification scheme in order to characterize the games. The advantages and disadvantages of the two different kinds of learning methods — self-training and team oriented education — are also shown with the help of the classification scheme.

This paper addresses the benefit analysis for the integration of workflow management tools. A special focus is set on non-productive tasks, such as service and administration. An example is described that uses an evaluation of a process chain in customer order processing of an aluminium factory with two different levels of detail. An overall examination is done first, in order to identify possible points of improvement in the process chain. Then, a detailed analysis of these subtasks is performed. The two examinations are performed with different simulation tools by two research teams. Their findings are combined in a proof scenario to show the expected performance of the final order processing system.

This paper discusses a process-oriented approach for designing organizational structures of production systems. Based on a suitable characterization of order related processes on one hand, and the personnel on the other hand, organizational structures with a high performance can be defined. The concept of shaping process-oriented organizational structures is connected to a simulation-aided approach in order to evaluate the dynamic behavior of planned production systems and to perform the planning procedure in a flexible and efficient way. The dynamic analyses are carried out using the simulation tool FEMOS.

The integrated simulation game for planning and reorganizing production systems has been developed at the ifab-institute in order to engage the awareness of the players for actual problems in real production systems. During the planning game the participants have to act on operative level as well as on strategic issues. First they have to plan and control the production of an existing assembly system for producing bicycles in planning teams. The system is modeled using the simulation tool FEMOS. Running the factory the teams are going to detect weak points inside the existing system. This experience is the basis for reorganizing the assembly system afterwards. The paper consists of demonstrating the principle structure of the planning game, the material used as well as an illustration of different planning results obtained by playing the game with students and professionals.

This paper discusses an object-oriented approach applying an integrated database for production systems. The basis for integration is an object-oriented Product/ Production-Model (PPM) which has been developed at an interdisciplinary research center of the University of Karlsruhe. Based on this object-oriented PPM, new ways of organizing engineering processes become possible. By using predefined methods of the database objects, the development of modular software tools is enabled. The common database ensures redundancy-free data management, uniform data structures for all relevant views and avoids repeated input of basic data. As an application for the described methods, the paper discusses a new planning approach for the design of production systems based on the PPM and an integrated computer aided library of planning methods.

Life Cycle Engineering of complex products traditionally does not aim at complete product reuse or reutilization but on that of parts and components. Therefore, disassembly is inevitably necessary, which underlines the central position of disassembly in Sustainable Life Cycle Engineering. It is uncontested that disassembly is, in comparison to assembly, charged with uncertainty. In order to consider this uncertainty, various approaches have been developed. One of these are adaptive dynamic process plans, which allow to derive optimal disassembly sequences depending on the actual disassembly state. Following this idea, two problems have to be solved. The first one is to develop a modelization of this uncertainty and of possible disassembly sequences following a certain disassembly state. On the other hand, it is necessary to collect knowledge about the actual state of the disassembly process and all relevant decision parameters. Especially Stochastic Disassembly Networks seem to be an appropriate approach to cover the first problem. Solving the second problem requires continuous interaction and communication between the disassembly worker and the dynamically developing process plan. This interaction is the basis for a suitable decision making, e.g. changing the disassembly strategy or breaking off disassembly with final removal of harmful substances.

This paper discusses a simulation aided planning game in the field of redesigning work structures. The game deals with a bicycle production and mainly covers the following three aspects: to enhance the understanding of problems and solving in the field of work structuring, to enable teamwork practise and to awake interest in using simulation tools for analysis of production systems. The planning game is supported by a guideline of work structuring for a suitable procedure and the simulation system FEMOS for dynamical analysis of planned systems.

Due to increasing international competition, productive enterprises are currently searching for measures to improve their order processing. As the major potentialities for further improvements are strongly connected to the organization of production systems, the organizational performance has to be investigated and evaluated.

To meet logistic goals and market demands industrial organizations have to reconsider their structures. Smaller units with an adequate control strategy seem to fulfil these goals better than centralized structures. Therefore, the question arises, which PPC-principle fits best a given manufacturing system. Analysing the procedure of capacity balancing reveals a systematic way for the investigation of various control strategies. It is shown that control strategies can be attributed to three parameters, namely order sequence, order quantity and initialization logic. In combination with an appropriate simulation program and certain expertise the best suitable control strategy for a given manufacturing structure can be developed.