• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.16 no.1
• /
• pp.124-133
• /
• 2017

In the current lighting market, LEDs that have a high luminous efficiency, a long life and consume less power have emerged as next generation lighting. Owing to various designs and sizes of LEDs, the production process of existing LEDs involves many tasks that require manual labor; hence, the assembly of LEDs necessitates manpower. Because of the use of manpower, the production costs of LEDs increases and production efficiency decreases. Recently, the assembly parts of LEDs have been standardized for minimizing manual labor, and an LED is developed as an LED panel. The automatic assembly system produces LED convergent lighting by assembling two LED panels and one diffusion cover. To increase the production efficiency of the LED convergent lighting module, it is important that the development of a feeder can continuously supply the LED panels is required, and whose design has sufficient stability. The automatic assembly system of the LED convergent lighting module consists of two feeders, which convey LED panels and diffusion covers to a main conveyor, which assembles the lifted panels and covers. In this study, structural analysis and fatigue life for forced loads on the conveyer line of the feeder in the process of lifting LED panels and diffusion covers of each feeder, is analyzed. In addition, the drive of the belt constituting the conveyor line of each feeder is simulated, and the dynamic characteristics of the belt is analyzed using the virtual engineering method.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.40 no.4
• /
• pp.211-220
• /
• 2017

The application of the theoretical model to real assembly lines has been one of the biggest challenges for researchers and industrial engineers. There should be some realistic approach to achieve the conflicting objectives on real systems. Therefore, in this paper, a model is developed to synchronize a real system (A discrete event simulation model) with a theoretical model (An optimization model). This synchronization will enable the realistic optimization of systems. A job assignment model of the assembly line is formulated for the evaluation of proposed realistic optimization to achieve multiple conflicting objectives. The objectives, fluctuation in cycle time, throughput, labor cost, energy cost, teamwork and deviation in the skill level of operators have been modeled mathematically. To solve the formulated mathematical model, a multi-objective simulation integrated hybrid genetic algorithm (MO-SHGA) is proposed. In MO-SHGA each individual in each population acts as an input scenario of simulation. Also, it is very difficult to assign weights to the objective function in the traditional multi-objective GA because of pareto fronts. Therefore, we have proposed a probabilistic based linearization and multi-objective to single objective conversion method at population evolution phase. The performance of MO-SHGA is evaluated with the standard multi-objective genetic algorithm (MO-GA) with both deterministic and stochastic data settings. A case study of the goalkeeping gloves assembly line is also presented as a numerical example which is solved using MO-SHGA and MO-GA. The proposed research is useful for the development of synchronized human based assembly lines for real time monitoring, optimization, and control.

• IE interfaces
• /
• v.23 no.1
• /
• pp.58-67
• /
• 2010

The purpose of this paper is to present the development processes of the assembly line tester of power transmission for lift truck. Because power transmission is most important part of lift truck, all assembled powertrain parts must be inspected for operational defects, pressures and RPM. Developed assembly line tester is designed to take about 25 minutes for inspecting each assembled power transmission and located it at the end of assembled line. The assembly line no-load tester consists of three parts: (1) the driving hardware part; for installing and operating the transmission. (2) control PCB part; send data from sensors to a computer and control driving part, (3) operation software of no-load tester; for an automatic inspection or manual inspection, for database management and printing transcripts.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2024.01a
• /
• pp.481-484
• /
• 2024

본 논문에서는 레고(LEGO®) 조립 설명서를 생성하기 위해 딥러닝을 이용한 조립 및 설명서 생성 시스템을 제안한다. 이 시스템은 사용자가 제공한 단일 이미지를 기반으로 레고 조립 설명서를 자동 생성한다. 해당 시스템은 딥러닝 기반 이미지 분할 기술을 활용하여 물체를 배경으로부터 분리하고 이를 통해 조립 설명서를 생성하는 과정을 포함하며, 조립을 위한 알고리즘을 새로 설계하였다. 이 시스템은 기존 레고 제품의 한계를 극복하고, 사용자에게 주어진 부품으로 다양한 모델을 자유롭게 조립할 수 있게 한다. 또한, 복잡한 레고 조립 과정을 간소화하고, 조립의 장벽을 낮추는 데 도움을 준다.

• The Journal of the Korea Contents Association
• /
• v.9 no.1
• /
• pp.73-80
• /
• 2009

This paper describes a sensor-based remote monitoring technique for ship block assembly and implementation of a prototype system. Instead of manual processing or optical measuring devices, the proposed approach attaches some distance-measuring sensor nodes to ship blocks. Remote monitoring of the assembly status makes it possible to minimize marginal errors during ship block assembly process, and helps efficient ship building.

• Transactions of the Korean Society of Machine Tool Engineers
• /
• v.16 no.5
• /
• pp.162-165
• /
• 2007

TFT-LCD process has two advantages as compared with the semiconductor-process. It is that cycle time is short and number of the final products are small. But it needs complicated inspection / assembly line to be treated manually and much higher labor costs in the TFT-LCD process. Also, It is necessary to build PICS(Production Information and Control System) which is automated and intelligent. In this paper, an automated process of LCD module assembly line that can increase productivity and reduce the cost of production to strengthen the competitiveness corresponding with global market is planned in comparison with its manual/semi-auto. It is noted that The automated line for COG$\sim$FOG process replacing with the existing facilities had the following effects; the productivity is increased to about 1.5 times and labor cost reduced 85%. In addition, whole assembly line can be short and simple.

• Proceedings of the ESK Conference
• /
• 1997.10a
• /
• pp.433-436
• /
• 1997

Automobile assembly tasks consist of many kinds of manual work which are very stressful to workers because of repetitive poor working postures and dealing heavy weights. To decrease the level of workload, it is necessary to evaluate the workload quantitatively. In this study, a workload evaluation method based on EMG was experimentally evaluated. We measured EMG at 6 main muscles with 2 healthy male workers during doing 9 assembly tasks, which were selected as high workload jobs. The tasks were decomposed into 36 elementary tasks. The workload was calculated through an equation with %MVIS and work duration time. To evaluate the result, subjective discomfort on the tasks was assessed by 29 workers. By the calculated workload, we were able to ranked the workload of tasks, elementary tasks. The comparison between the EMG-based workload and subjective rating showed a positive correlation(P-value=0.0246). We think it is possible to adapt the EMG-based workload evaluation technique to all assembly tasks by expending the experi- ment size.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.18 no.5
• /
• pp.594-601
• /
• 2015

The purpose of this research is to propose a maintenance support system for deciding assembly sequence of the product and appropriate tools that are used to assembly and disassembly of parts in the product when geometric properties of the product. The digital maintenance system (DMS) is developed to generate the maintenance guideline and the initial experiment is conducted especially for an underwater weapon system with cylindrical structure. DMS considers four factors to find the efficient assembly and disassembly procedure automatically: (1) assembly tree, (2) properties of each part, (3) distance from the center of the product, and (4) volume. Based on the factors, DMS simulate the movement of each tool virtually and the properties of tools are investigated to find an appropriate tool for using assembly and disassembly of each part in the product. The proposed approach integrates modeling, simulation, data configuration, and virtual reality to allow a development of preliminary maintenance guidance.

• Journal of Korea Society of Industrial Information Systems
• /
• v.26 no.4
• /
• pp.19-32
• /
• 2021

It is well known that any maintenance works for aircrafts must be carried out strictly in accordance with the specified maintenance manuals, especially for military airplanes. According to our previous studies, the largest portion of the maintenance jobs for military aircrafts is found to be related to the assembly/disassembly of various parts, which requires precise understanding of the work procedures as well as correlation between interconnected parts let alone grasping of the exact shapes of parts involved. However, the conventional manuals for aircraft maintenance have failed to provide enough information required for the efficient maintenance except for simple texts and vague pictures, which are far from being sufficient sets of information. On the contrary, unlike incomplete conventional manuals with poor contents, 3D modeling SW could provide us with not only powerful visualization tool even to see through inside any assembly but also freedom to watch parts under test from any angle we want. In addition, the maintenance personnels could learn the precise maintenance procedures through repeatedly watching 3D animated version of the maintenance work as if they were on the field. In this study, we have suggested the efficient procedures to develop 3D manual for aircraft maintenance using 3D modeling SW, Solidworks and implemented a 3D maintenance manual for Integrated Drive Generator(IDG) in Boeing 747. Characteristics of the developed 3D manual has been analyzed in comparison with the conventional ones as well. It is shown that the suggested method could be easily applied to develop a 3D maintenance manual for commercial airplanes since the maintenance works involving assembly/disassembly of major parts are very similar regardless of aircraft types.

• Journal of the Korean Society of Industry Convergence
• /
• v.27 no.3
• /
• pp.535-546
• /
• 2024

This research aims to develop a model to objectively and quantitatively measure the skill level of aircraft body assembly workers. Because aircraft body assembly is predominantly a manual process, skills management is a key factor of manufacturing competitiveness. Currently, skills management relies on the subjective judgment of supervisors, which lacks objectivity and reliability. As a remedy, this study proposed a systematic skill management model based on objective and quantitative evaluation criteria. By considering prior research, we developed an evaluation model that takes into account both expertise and versatility of a worker. The model selected five major tasks required for aircraft body assembly and established evaluation criteria considering the difficulty and maturity of each task. We then conducted a pilot evaluation with over 200 workers in four SMEs to validate the practicality and effectiveness of the model. Consequently, we identified and addressed the limitations of the existing evaluation method, subdivided the skill levels based on the performance capabilities of each task, and proposed a career growth path. The developed evaluation model offers critical data for executives and managers to determine work assignments, education, training, performance incentives, and wages. It is expected to enhance the attraction of new talent and systematize skills management in aviation manufacturing in the future.