Truck Assembly Line Research Articles

System framework of adopting additive manufacturing in mass production line

ABSTRACT System framework is for adopting additive manufacturing (AM) in a mass production line where AM processes are integrated to customize protective parts for manual tools that are found to cause damages of products. The system ensures AM processes are adopted to meet the requirements of functionalities, reliability, line balancing, and the production rate like other conventional processes. The proposed system is different from other AM applications in sense that product designs and fabrications become integrated parts of a production flow. The effectiveness of the system framework is validated as the solution to fix surface mutilations in a truck assembly line.

Performance Improvement of Truck Assembly Line through Modeling and Simulation Using Arena Software

Due to global completion in the automotive industry, productivity improvement is vital in these industries. In automotive assembly lines, productivity loses are attributed to bottlenecks, long processing time in workstations and underutilization of resources. The purpose of this research is to evaluate the performance of the production system, analyze the bottlenecks in different parts of the workstation, their capacity and constraints. Also, develop different scenarios for improvement. To achieve this objective, a simulation model was developed using Arena Software to analyze bottlenecks in each workstation. The analysis was based on the queue in the system to identify the longest queue in workstations. After analysis of the assembly line, the result showed that the longest waiting time observed is cab preparation and drop, bumper, engine subassembly fitment of soundproof with respective numbers 14.4, 13.97, 13.00, 13.70 minutes, with respective average number waiting of 24.87%, 17.57%, 25.91% and 23.39%. Using different scenarios for the improvement of the production line showed that the waiting time observed in-cab preparation and drop, bumper, engine subassembly, fitment of soundproof has greatly reduced for the two workstations added and three operators respectively from 14.4 to 3.97 and 3.1, from 13.97 to 3.77 and 2.48, from 13.00 to 4.21 and 3.83, from 13.70 to 0.00 and 2.37 minutes, with respective average number waiting from 24.87% to 5% and 2%, from 17.57% to 5% and 0.9%, from 25.91% to 5% and 4%, and from 23.39% to 0.00% and 3%. To conclude the research study was able to demonstrate the modelling approach using simulation for analysis of a production line assembly. The contribution of this research was so enormous, this study has improved the output production up to 144%.

Truck Assembly Line Reconfiguration to Reduce Cycle Time with Lean Manufacturing Approach in the Indonesian Automotive Industry

The automotive industry is one of the industries that plays a major role in Indonesia’s revenue sources, one of which is in meeting daily needs, especially for transportation and logistics. This causes the growth of truck production targets each year and has become one of Indonesia’s focus to target 1.29 million trucks produced in 2020. This study aims to minimize production time with the optimal number of workstations to minimize costs that will come out for increasing production capacity in truck assembly lines in Indonesia. The study was conducted with a lean manufacturing approach to analyze the waste contained in the assembly line. The study began by calculating time for each work using the time study method. The time obtained is then inputted to the mixed integer linear programming mathematical programming model developed in the LINGO 17.0 software. The result of data processing in the LINGO 17.0 software is the allocation of each job to the new workstation to get the production cycle time in accordance with the production takt time, and also the total idle time of the new assembly line.

A multi-objective programming approach to develop an ergonomic job rotation in a manufacturing system

A worker assignment job rotation problem with the heterogeneous workers and the jobs with different workload level is presented in this paper. Both productivity and ergonomic criteria are considered in the problem and a multi-objective mixed-integer mathematical model is proposed to implement an ergonomic job rotation in a production system. The main objective of the model is to balance the daily workload that the workers are exposed together with reducing the production cycle time in the studied system. The proposed mathematical model is applied to a part of a truck assembly line. The model is programmed by GMPL mathematical modeling language and is solved by employing Gurobi solver. The computational results show the capability of the proposed model to optimize both objectives of the job rotation.

Improvement of production layout based on optimum production balancing scale results by using Moodie Young and Comsoal method

This research was conducted at a make to order production system company which is engaged in the car body of the vehicle. One of the products produced is dump truck which is one kind of transportation for the transport of goods equipped with hydraulics to facilitate goods’ loading and unloading process. The company has 7 work stations with different cycle times. Companies often experience delays in order delivery. The production process on the production floor has not been done optimally where there is a build up of work in process in some work centres. The build up of work in process (WIP) products is seen in the welding and painting stations. Stacking that occurs on the production line may cause the company to be liable for damages due to delays in product completion. The WIP occurs due to unbalanced paths can be seen from the variance of cycle time of each station is very diverse. The time difference of each work element is due to the allocation of work elements to each work centre unevenly. On the basis of the allocation of uneven work elements, the dump truck assembly line is made. The analysis is done by using Moodie Young and Comsoal method to do the balancing of production line. The result of layout improvement by using systematic layout planning (SLP) method is change the composition of the work centre from 7 into 4 work centre which enables the movement of material to be more effective and efficient so that it can get an efficient and effective production trajectory and can solve existing problems. The result of the track balancing is then used as a guide in constructing a new layout based on the balancing result with the most optimum method.

Minimising work overload in mixed-model assembly lines with different types of operators: a case study from the truck industry

This paper considers the problem of sequencing mixed-model assembly lines (MMALs). Our goal is to determine the sequence of products to minimise work overload. This problem is known as the MMAL sequencing problem with work overload minimisation: we explicitly use task operation times to find the product sequence. This paper is based on an industrial case study of a truck assembly line. In this industrial context, as a reaction to work overloads, operators at the workstations finish their tasks before the product reaches the next workstation, but at the expense of fatigue. Furthermore, there are different types of operators, each with different task responsibilities. The originality of this work is to model this new way of reacting against work overloads, to integrate three operator types in the sequencing model and to apply the developed methods in a real industrial context. To solve this problem, we propose three meta-heuristic procedures: genetic algorithm, simulated annealing and a combination of these two meta-heuristics. All the methods proposed are tested on industrial data and compared to the solutions obtained using a mixed-integer linear programme. The results show that the proposed methods considerably improve the results of the current procedure used in the case study.

Wireless information system for rotating operators in human-based assembly lines

This article suggests an information system for the support of human operators in an assembly line. The information system utilises mobile devices and a pushlet-based infrastructure for automatically providing the mobile line operators with information in real time. The Radio Frequency Identification technology is used for tracking the location of a vehicle, its parts and the operator on the assembly line. An intelligent decision-making algorithm is paired with this information along with a communication infrastructure for enabling a dynamic job rotation during assembly. The system enables the reduction of errors in multivariant assembly lines, the reduction of time for information retrieval and the efficient allocation of assembly tasks to operators. The system has been implemented in a truck assembly line.

Tool for Improving Operating Points in Multi Model Assembly Lines

Manufacturing companies are facing highvariant diversities of their products. The degree of variant diversity increasesalongthe value chain. Hence, assembly is forced to deal with the highest diversity. These fluctuating workloads affect the utilization rate in multi model assembly lines. Thereby, constant cycle times lead to losses in time due to the model mix. Furthermore, losses can result from gaps between exact workloads and human capacities in the workstations.Optimal operating points are defined as the ideal combination of concurrent sub goals like utilization rate and throughput rate. The identification of such operating points for assembly lines with planned product sequences shows up as a task for capacity planning and line balancing. Several analytic line balancing methods were developed in the past aiming for instance at minimal cycle times. However, methods for operational decisions on cycle time and overall production capacity are still rare. Simulation methods show potential to fill this gap. They allow the modeling and simulation of specific and complex production systems. This paper describes a planning method and a simulative tool for the identification of optimal operation points. The aim of optimal operating points is a reduction of time losses due to the model mix.Based oncurrent approaches for simulative line balancing, a planning tool has been developed. Working with defined product sequences, thistool supports the variation of parameters like the cycle time. Effects on productivity and time losses can be analyzed. Optimal operating points can be identified. Furthermore, the tool can visualize specific product sequences with corresponding workloads during the shift. It supports staff decisions on improvements in production. Moreover, results can be used for decisions on staff planning and staff development. The tool has been validated by a case study in a truck assembly line.

An experimental investigation on push force and its perception during a flexible hose insertion task encountered in a truck assembly line

The push force and its perception when inserting a flexible hose laterally into a connector were investigated. Effects of hose diameter, glove, target position and obstacle condition were studied. Maximum voluntary insertion forces (MVFs) under similar working conditions were also measured. The larger the diameter, the higher the force required. The peak axial forces for the hoses of 6, 12 and 16 mm in diameter were on average respectively 94, 122 and 184 N, representing 45%, 61% and 93% of MVF. Glove condition, target position and obstacle did not significantly affect the axial insertion force and moment, but they did affect effort perception. Lower effort was perceived with gloves and high and near position. High intra- and inter-individual variability in insertion force for a given hose may suggest that feedback of successful insertion was insufficient. The recognition of a successful insertion must be ensured to avoid unnecessary extra force exertion.Practitioner summary: The effects of glove, hose diameter, target location and obstacle on push force and its perception were studied when inserting a flexible hose. Solutions for improving the recognition of a successful insertion and the hose/connector system design must be found to reduce force exertion to safe levels.

Optimization and Improvement of the Characteristic of Material Flow of Mixer Truck Assembly Line

In order to achieve the supply of materials on the concrete mixer assembly line timely and accurately, in this paper, the process, production features and actuality of materials supply on the concrete mixer assembly line were analyzed, the stations of the assembly was combined, and function mode of the storage was changed to active distribution. Then the material handling process was optimized using material handling design system. Finally, the effective implementation of material distribution was ensured based on the on-site management.

Evolutionary algorithms for flowshop sequencing with non‐unique jobs

AbstractSequencing problems are difficult combinatorial problems because of the extremely large search space of possible solutions and the large number of “local” optima that arise. Unlike other NP‐hard combinatorial problems, the search space, in general, for sequencing problems (under the makespan objective) consists of sequences with objective function values that lie within only a relatively small amount of each other. This means that when a change is made to the sequence, an improvement or non‐improvement is not easily recognised. This makes the problem much more difficult to solve. A number of constructive heuristics exist that obtain good solutions in a short period of time, however, the output of such algorithms is generally a single sequence which may not be feasible or preferred with respect to industry constraints. Other heuristic algorithms such as Simulated Annealing (SA) and Tabu Search (TS) have also been applied and successes have been reported. However, the performance is dependent upon a number of finely tuned parameters and the output is again only a single solution. For these reasons, Evolutionary Algorithms (EAs) may be suitable solution strategy, for which limited research has been performed. In this research, a number of new EAs have been proposed and a number of modifications have been made to several constructive algorithms to cope with non‐unique jobs or jobs with multiple demands. A numerical comparison of a number of benchmark problems and real data of a truck assembly line has also been presented.

Evolutionary algorithms for flowshop sequencing with non-unique jobs

Sequencing problems are difficult combinatorial problems because of the extremely large search space of possible solutions and the large number of “local” optima that arise. Unlike other NP-hard combinatorial problems, the search space, in general, for sequencing problems (under the makespan objective) consists of sequences with objective function values that lie within only a relatively small amount of each other. This means that when a change is made to the sequence, an improvement or non-improvement is not easily recognised. This makes the problem much more difficult to solve. A number of constructive heuristics exist that obtain good solutions in a short period of time, however, the output of such algorithms is generally a single sequence which may not be feasible or preferred with respect to industry constraints. Other heuristic algorithms such as Simulated Annealing (SA) and Tabu Search (TS) have also been applied and successes have been reported. However, the performance is dependent upon a number of finely tuned parameters and the output is again only a single solution. For these reasons, Evolutionary Algorithms (EAs) may be suitable solution strategy, for which limited research has been performed. In this research, a number of new EAs have been proposed and a number of modifications have been made to several constructive algorithms to cope with non-unique jobs or jobs with multiple demands. A numerical comparison of a number of benchmark problems and real data of a truck assembly line has also been presented.

The cost of work on a vehicle assembly line.

Abstract The physiological cost of work on men working on a truck assembly line was measured. Twenty subjects took part in the study: all had their heart rates measured during work, leisure and sleep. Thirteen subjects had their oxygen consumption measured at work using a newly described respirometer (Miser). Results confirmed that such work may be classified as light industrial with an energy expenditure of 120-200 W Mean heart rates during work were 91 ± SD 8 bt min-1;, mean relative work load was 24 ± SD 4% and mean relative heart rates were 21 ± SD 7%. The mean of the ratios of work, sleep and leisure: sleep heart rates were 1 -45 ± SD 015 and 1-28 ± SD 012 respectively.