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The purpose of this paper is to determine how kitting, compared to continuous supply, affects the time spent by the assembler fetching parts in manual assembly.

The paper is based on an experimental setup at the Saab Automobile assembly plant in Trollhättan, Sweden. Experienced assemblers were studied as they performed the same assembly operations in ten different configurations. Each configuration consisted of a different arrangement in terms of how parts were presented. The use of kits to present parts was compared to parts presentation through continuous supply, where each part number was presented in a separate container.

The time for fetching parts is significantly shorter when parts are presented through kitting instead of through continuous supply. Furthermore, the shorter fetching time is not just related to a shorter distance between assembly object and parts presentation, which can often be achieved through kitting. The reduction of time spent searching for parts is also considerable.

The results of the paper provide valuable input in the design of assembly and materials supply systems, as they enable a better understanding of the relative performance of the materials feeding principles of kitting and continuous supply.

Previous studies of kitting and its impact on assembly are mostly conceptual or qualitative, whereas quantitative studies are scarce. The current paper provides a substantial contribution by quantifying the effects that kitting, compared to continuous supply, has on the time spent fetching parts.

The purpose of this paper is to investigate a strategic change from parallel cell‐based assembly (old) to serial‐line assembly (new) in a Swedish company with special reference to how production system design elements affect both productivity and ergonomics.

Multiple methods, including records and video analysis, questionnaires, interviews, biomechanical modelling, and flow simulation were applied.

The new system, unlike the old, showed the emergence of system and balance losses as well as vulnerability to disturbances and difficulty handling all product variants. Nevertheless, the new system as realised partially overcame productivity barriers in the operation and management of the old system. The new system had impaired ergonomics due to decreased physical variation and increased repetitiveness with cycle times that were 6 per cent of previous thus increasing repetitiveness, and significantly reducing perceived influence over work. Workstations' uneven exposure to physical tasks such as nut running created a potential problem for workload management. The adoption of teamwork in the new system contributed to significantly increased co‐worker support – an ergonomic benefit.

Design decisions made early in the development process affect both ergonomics and productivity in the resulting system. While the time pattern of physical loading appeared to be controlled by flow and work organisation elements, the amplitude of loading was determined more by workstation layout. Psychosocial conditions appear to be affected by a combination of system elements including layout, flow, and work organisation elements. Strategic use of parallelisation elements in assembly, perhaps in hybrid forms from configurations observed here, appears to be a viable design option for improved performance by reducing the fragility and ergonomic problems of assembly lines.

The interacting design elements examined here pose potential “levers” of control by which productivity and ergonomics could be jointly optimised for improved total system performance.

In recent years, assembly lines have been reintroduced in the Swedish automotive industry and, in many cases, have replaced those so‐called alternative assembly systems which had their roots in the 1970s. This paper reviews and evaluates some explicit reasons given for the return to the assembly line. It also considers whether the decisions to replace alternative assembly systems with assembly lines may have been driven by other factors and mechanisms than those implicit in these arguments and, if so, what other factors could explain their reintroduction. There is also a discussion of which dimensions that should be taken into account when choosing between alternative assembly systems and assembly lines and empirical data are used to shed more light on the issues discussed in the article. The authors report one study that compares automobile assembly in an alternative assembly system with assembly of the same products after introducing an assembly line. They also briefly discuss reasons for and experiences from the recent introduction of alternative assembly systems in the Japanese electronics industry. In this case, so‐called cellular assembly systems have replaced assembly lines.

The purpose of this paper is to provide an understanding of how the materials feeding design at a workstation impacts the assembly process performance, in terms of manufacturing flexibility, process support, materials planning and work task efficiency.

The empirical data are based on two embedded case studies performed in close corporation with two Swedish automotive companies; additional observations from more than 20 company visits in Japan, and small‐scale case studies performed in Japanese companies. To fully assess the work measurement figures, video recordings, work instructions and layout drawings were used to plot the operators' walking patterns, and it was then possible to map the whole work cycle for an operator. Industrial engineers, managers, group leaders, team leaders and operators were interviewed. Based on the literature review and personal experience from the small‐scale case studies carried out in Japan, the existing assembly systems' component racks were conceptually re‐designed. This led to two hypothetical assembly systems, which could be used for understanding the impact of materials feeding design on assembly process performance. The design of the new component racks and the choice of packaging types were made together with practitioners.

The paper shows that the design of component racks and choice of packaging types have a major impact on the assembly process performance. Component racks with a large depth and small width and tailored packages create important advantages over traditional Swedish component racks designed for EUR‐pallets. Line stocking is not always the best choice for materials feeding, but this paper shows that line stocking, especially in Swedish assembly systems, can be improved. Sequencing can thus be reduced, resulting in fewer problems when there are sequence breaks in the production flow. Component racks with small packages and large depth increase the work task efficiency, volume, mix, new products and modification flexibility. For example, free space is an important issue for these types of flexibilities. Component racks that are portable and easy to rearrange, together with free space, greatly facilitate handling of new product introductions or modifications of products. The new and old component can be displayed and fed to the same workstation, and if there is a larger change a whole segment of a component rack can easily be replaced by a new one between work shifts.

The scope of the study is limited to the conditions at workstations. Consequences for the materials flow upstream (i.e. internal materials handling, warehousing, transport, supplier processes, etc.) are not included, but must in further studies also be considered to avoid sub‐optimisation.

The paper highlights the fact that a shift in focus is necessary when designing workstations with component racks in Swedish companies, meaning that operators become the customers rather than the transport company or materials handler.

The purpose of this paper is to provide a contribution to the area of behavioural operations management (OM) by identifying key challenges in the use of discrete-event simulation (DES) to model people’s behaviour in OM.

A systematic literature review method is undertaken in order to assess the nature and scale of all publications relevant to the topic of modelling people’s behaviour with DES in OM within the period 2005-2017.

The publications identified by the literature review reveal key challenges to be addressed when aiming to increase the use of DES to model people’s behaviour. The review also finds a variety of strategies in use to model people’s behaviour using DES in OM applications.

A systematic literature review method is undertaken in order to include all publications relevant to the topic of modelling people’s behaviour with DES in the OM domain but some articles may not have been captured.

The literature review provides a resource in terms of identifying exemplars of the variety of methods used to model people’s behaviour using DES in OM. The study indicates key challenges for increasing the use of DES in this area and builds on current DES development methodologies by presenting a methodology for modelling people’s behaviour in OM.

The purpose of this paper is to determine whether man-hour efficiency of picking is affected by the use of batch preparation, compared to preparation of one kit at a time. This paper focuses on small kit preparation areas.

This paper is based on two experiments that were performed at a vehicle assembly plant and then analysed quantitatively.

The results provide a strong indication of the advantages associated with batch preparation, in terms of man-hour efficiency.

The fact that the effects identified during the experiments are substantial, over 20 per cent reduction of average time per picked component in Experiment 1 and 7 per cent in Experiment 2, indicates that the option of batch picking holds potentials for large cost reduction and should be considered when kit preparation systems are designed.

Limited research has dealt with the design of kit preparation systems, thus leaving considerable knowledge gaps. Previous research dealing with batch picking focuses on other environments than kitting and on large picking areas where batching can reduce walking distances. In contrast, the current paper focuses on small picking areas, which are common in industrial kitting applications. This paper provides a considerable contribution by demonstrating improvements in time efficiency that batch preparation can offer to small picking areas in addition to larger areas. The discussion also provides a basis for future research, which could focus on aspects other than time efficiency, such as the quality of kit preparation, and variables that might moderate the effect of batching.

Prior literature has widely established that the design of storage locations impacts order picking task performance. The purpose of this study is to investigate the performance impact of unit loads, e.g. pallets or rolling cages, utilized by pickers to pack products after picking them from storage locations.

An empirical analysis of archival data on a manual order picking system for deep-freeze products was performed in cooperation with a German brick-and-mortar retailer. The dataset comprises N = 343,259 storage location visits from 17 order pickers. The analysis was also supported by the development and the results of a batch assignment model that takes unit load selection into account.

The analysis reveals that unit load selection affects order picking task performance. Standardized rolling cages can decrease processing time by up to 8.42% compared to standardized isolated rolling boxes used in cold retail supply chains. Potential cost savings originating from optimal batch assignment range from 1.03% to 39.29%, depending on batch characteristics.

This study contributes to the literature on factors impacting order picking task performance, considering the characteristics of unit loads where products are packed on after they have been picked from the storage locations. In addition, it provides potential task performance improvements in cold retail supply chains.

The purpose of this paper is to propose a decision model to choose between kitting and line stocking at the level of single parts, while taking into account the variable operator walking distances. Different ways of feeding assembly lines, such as kitting and line stocking not only have an impact on in-plant logistics flows but also determine the amount of stock that is available at the line. This, in turn, has an impact on operator walking distances during assembly.

A mixed integer linear programming model is developed for the assignment of parts to one of both methods, and to be able to extensively test the model, an algorithm is created for the construction of representative datasets.

Parts are often kitted because of a space constraint at the line, but even without a space constraint, the shorter walking distances might give preference to kitting. An analysis is presented that demonstrates how specific part characteristics influence the chances of a part being kitted.

Our research model can be extended to include, e.g., the study of alternative in-plant logistic designs and the outsourcing of kitting to a third-party logistics provider (3PL) or to the suppliers.

The objective assignment model and the insights obtained from it are valuable for logistics and production engineers that otherwise have to rely solely on intuition. In situations with thousands of components, intuition mostly falls far short.

First, existing models do not consider variable walking distances, which are shown to have a crucial impact on the decision. Second, the data instances created allow for a systematic comparison of future research in the field.

Assembly systems require uninterrupted components' availability to feed workstations. This paper aims to propose a methodology to help managers in evaluating and selecting the most suitable policy for materials delivery to the shop floor. The analysis focuses on three basic policies, namely kitting, just in time kanban‐based continuous supply and line storage, even including class‐based hybrid policies.

Descriptive models are developed to design components' delivery systems and to compute their performances. Empirical criteria are utilized to associate specific policies to components classes in order to implement customized hybrid line feeding policies. A case study is then included to exemplify the method application and to show its capabilities as a decision making tool.

Hybrid feeding policies may be preferable to a single feeding policy common to all components. This is shown in a representative case study. However, in general there is a priori superior method and only a comparison of alternative feeding policies based on objective performance measures can determine the best approach in specific industrial applications.

The methodology is aimed at preliminary sizing and selection of alternative line feeding systems in deterministic environments. It is not intended for detailed performance analysis of assembly systems.

Production managers are given quantitative decision tools to properly select the components' delivery method at an early decision stage. This allows trade‐offs between alternatives to be explored in order to deploy customized feeding policies differentiated on components basis to better fit specific company requirements.

The paper extends previous descriptive models for line feeding systems and includes the possibility of hybrid policies.

Discusses production models for final assembly in the automotive industry and also reports on the performance of one final assembly plant representing an innovative production model, namely the Volvo Uddevalla plant. Briefly considers some issues and pitfalls in current production model discourse, and in this connection introduces a distinction between two manufacturing models and broader industrial models. Describes two manufacturing models for final assembly work as namely the “serial flow model” and the “parallel flow model”. Discusses the Japanese “lean production”, sometimes synonymous with “Toyotism”, as an industrial model and the impact of socio‐economic and socio‐cultural contexts on manufacturing models and industrial models. Concludes that the Uddevalla plant highlights the paradox that long cycle time work in parallel flow assembly systems is in fact more efficient than short cycle time work in serial flow systems, provided that suitable technical and administrative preconditions exist. Therefore, the engineering point of view and the Swedish experiences of innovative manufacturing systems should be carefully considered in the current production model discourse.