This work is the final part of the Master of Science degree in Industrial Design Engineering towards Production Design, at Luleå University of Technology. This project has been conducted during the spring of 2017 at Alimak Hek. The task has been to analyze material handling, material presentation and why material shortages occur at the industrial hoists final assembly stations. To get an understanding of the system, interviews and observations were conducted. A literature study was carried out to find current knowledge and different solutions. To involve the workers in the process and to check if the problems were understood correctly a workshop was conducted. This was also an opportunity to discuss desired future state and ideas with the workers. Another way to look at potential solutions was through the benchmarkings. These were both conducted internally and at other companies where different solutions for material handling was studied.   The material in focus has been fastening material. This was stored in bins at racks. These racks were placed at the assembly stations and the two big racks have been the focus of this project. The problems at these storages has been that the refilling did not work as it was supposed to. The old system was an order list with which material could be ordered from the main storage at Alimak, this however is not used any more. The system of today is that the empty bins are collected and put on a pallet to be sent to the main storage for refilling. The problem with this is that the workers did not take the bins when they were empty but rather went to a different storage to look there. This meant that the material sometimes got totally emptied at all racks before the bins were sent to refilling. This made for urgent needs where workers had to go to the storage themselves to get something refilled. Another problem was that these storages were placed behind the fixed stations which made them hard to get to and see. The bins used in today’s system were not all marked the same way and an old system for numbering was still partly used. The bigger storages were divided so that one should have the stainless material and the other should have the galvanized/zinc-coated material. This together with the other aspects made it hard to know where the bins should be and sometimes all bins of one kind was put in the same rack.   To fix these problems different suggestions were made. The use of a two-bin system has been suggested because of its simplicity and the potential it has to avoid a lack of material to arise. The two racks of today should be combined into one and moved to a more visible place. This would make the refilling easier and reduce the need to search for material at different places. Two general layouts have been developed, and the open layout has been suggested to be implemented because of the accessibility it would bring to the system. The approximate size of the rack and bins needed have been put forward and different suggestion for order in the rack has been made. The marking of the bins and rack has also been discussed and this should be made distinct so it is easy to see and read.

Purpose – The purpose of the study is to propose a framework for standardized workstations with focus on operators work activities and material presentation on a mixed-model assembly line. In order to fulfill the purpose, it was decomposed into three research questions: Research question 1: What problems in existing manual workstations can be identified, regarding work activities and material presentation? Research question 2: What can be considered regarding operators' work activities in creation of standardized workstations for a mixed-model assembly line? Research question 3: What can facilitate the work performance and ergonomics of operators when designing material presentation for standardized workstations for a mixed-model assembly line? Methodology – This study was carried out inductively through analysis of empirical data from a case study against existing theories from a literature study. Theories were in the areas of mixed-model assembly line, workstation design, material presentation, work activities, ergonomics and human aspect, and standardization and flexibility. To gather empirical data, a document study, observations and interviews were conducted at one case company. Findings – The study resulted in a framework for work activities and material presentation in standardized workstations on a mixed-model assembly line within the perspectives of ergonomics, standardization and non-value-added work. Results indicated on decreased efficiency if the involvement of human factor and standardization were insufficient in the workstation design, by increased non-value- added work and decreased ergonomics. Implications – The proposed framework intended to support companies to merge assembly lines into a mixed-model assembly line with low automation. Limitations – The framework in this study only focused on workstations' workactivities and material presentation. Workstations are linked to more than these two areas therefore should more areas be included in merging assembly lines. This framework had the perspectives of ergonomics, standardization and non-value-added work, more perspectives should be considered in a merger.

Modern manufacturing systems seem to be shifting from mass production to mass customisation, which means that systems must be able to manage changes in customer demands and requirements, new technology as well as environmental demands. This in turn leads to an increase in product variants that need to be assembled. To handle this issue, well designed and presented information is vital for assembly workers to perform effective and accurate assembly tasks. In this thesis the main focus has been to find factors that affect human performance in manual assembly. A literature review was made on the subject of manufacturing and usability as well as basic cognitive abilities used to utilise information, such as memory. This investigation identified applicable factors for assessing human cognitive performance within the research field of manufacturing. The thesis further investigates how some of these factors are handled in manual assembly, using case studies as well as observational studies. The results show that how material and information are presented to the assembler needs to be considered in order to have a positive effect on the assembly operation. In addition, a full factorial experimental study was conducted to investigate different ways of presenting material and information at the workstation while using mixed assembly mode with product variants. The material presentation factor involved the use of a material rack compared to using an unstructured kit as well as a structured kit and the information presentation factor involved using a text and number instruction compared to a photograph instruction. The results showed that using a kit is favourable compared to the traditional material rack, especially when using a structured kit combined with photographic instruction. Furthermore, the use of unstructured kits can lead to better productivity and reduced perceived workload, compared to a material rack. Although they are perhaps not as good as using a structured kit, they most likely bring a lower cost, such as man-hour consumption and space requirements. However, the number of components in an unstructured kit needs to be considered in order to keep it on a manageable level. As a conclusion, several scenarios were developed in order to understand how different assembly settings can be used in order to improve human performance at the assembly workstation.