Final Assembly Line Research Articles

A case study: SMED & JIT methodologies to develop continuous flow of stamped parts into AC disconnect assembly line in Schneider Electric Tlaxcala Plant.

The competitiveness in the globalized environment highlights the importance of becoming more efficient in the execution of the company's operative and administrative processes in order to improve the level of customer service, delivery times, quality of products or services, as well as to optimize resources. The great advantage of implementing integrated logistics activities as a strategy to achieve this is undeniable. This paper, therefore, presents the methodology and the benefits obtained, which, with properly forecasted demand, aggregate planning methodology and the synchronization of some lean manufacturing techniques using tools like JIT (Just In Time) and SMED (Single Minute Exchange of Die), make the enterprise more competitive in delivery lead time, improve customer service level and reduce inventory. This case study involved some functional areas like Demand Planning, Materials Planning, the Manufacturing and Production Departments and the Warehouse Area. The principal objective of this research is to create a continuous flow of the stamped parts, from the Stamped Area to the final Assembly Line; in order to avoid sending the materials to the warehouse as currently happens.

Engineering Mathematical Analysis Method for Productivity Rate in Linear Arrangement Serial Structure Automated Flow Assembly Line

Productivity rate (Q) or production rate is one of the important indicator criteria for industrial engineer to improve the system and finish good output in production or assembly line. Mathematical and statistical analysis method is required to be applied for productivity rate in industry visual overviews of the failure factors and further improvement within the production line especially for automated flow line since it is complicated. Mathematical model of productivity rate in linear arrangement serial structure automated flow line with different failure rate and bottleneck machining time parameters becomes the basic model for this productivity analysis. This paper presents the engineering mathematical analysis method which is applied in an automotive company which possesses automated flow assembly line in final assembly line to produce motorcycle in Malaysia. DCAS engineering and mathematical analysis method that consists of four stages known as data collection, calculation and comparison, analysis, and sustainable improvement is used to analyze productivity in automated flow assembly line based on particular mathematical model. Variety of failure rate that causes loss of productivity and bottleneck machining time is shown specifically in mathematic figure and presents the sustainable solution for productivity improvement for this final assembly automated flow line.

Scheduling in the Aeronautical Industry Using a Mixed Integer Linear Problem Formulation

Scheduling is becoming much more important in every industry. At the same time, scheduling problems have been the subject of continuous research since the early days of operations research. However, the standard resource constraint scheduling problem (RCSP) usually does not cover all the characteristics of real world problems.In this work, we present an Event Based Mixed Integer Linear Problem (MILP) formulation for a Multimode Resource Constraint Problem (MRCSP) of direct application for some industries, as aerospace final assembly lines. Taking as a starting point one of the last MILP formulations for standard RCSP, its contribution is to provide a formulation which covers the multimode case and more general temporal constraints than the ones usually referred to in the literature.This publication focuses on the computational results, their relevance and their impact for a future extension to solving real world instances.

Part logistics in the automotive industry: Decision problems, literature review and research agenda

With the ongoing trend of mass-customization and an increasing product variety, just-in-time part logistics more and more becomes one of the greatest challenges in today’s automobile production. Thousands of parts and suppliers, a multitude of different equipments, and hundreds of logistics workers need to be coordinated, so that the final assembly lines never run out of parts. This paper describes the elementary process steps of part logistics in the automotive industry starting with the initial call order to the return of empty part containers. In addition to a detailed process description, important decision problems are specified, existing literature is surveyed, and open research challenges are identified.

Inspector Robot – A new collaborative testing system designed for the automotive final assembly line

Purpose – The paper aims to deliver an approach of how lightweight robot systems can be used to automate manual processes for higher efficiency, increased process capability and enhanced ergonomics. To show how these systems can be utilized in practice, a new collaborative testing system for an automated water leak test was designed using an image processing system utilized by the robot. Design/methodology/approach – The “water leak test” in an automotive final assembly line is often a significant cost factor due to its labour-intensive nature. This is particularly the case for premium car manufacturers as each vehicle is watered and manually inspected for leakage. This paper delivers an approach that optimizes the efficiency and capability of the test process by using a new automated in-line inspection system whereby thermographic images are taken by a lightweight robot system and then processed to locate the leak. Such optimization allows the collaboration of robots and manual labour which, in turn, enhances the capability of the process station. Findings – This paper examines the development of novel applications for lightweight robotic systems and provides a suitable process whereby the systems are optimized in technical, ergonomic and safety-related aspects. Research limitations/implications – A new automated testing process in combination with a processing algorithm was developed. Practical implications – To optimize and validate the system, it was set up in a true to reality model factory and brought to a prototypical status. Several original equipment manufacturers showed great interest in implementing the system in their assembly line. Social implications – The direct human–robot collaboration allows humans and robots to share the same workspace without strict separation measures which is a great advantage compared with traditional industrial robots. The workers benefit from a more ergonomic workflow and are relieved from unpleasant, repetitive and burdensome tasks. Originality/value – A lightweight robotic system was implemented in a continuous assembly line as a new area of application for these systems. The automated water leak test gives a practical example of how to enrich the assembly and commissioning lines, which are currently dominated by manual labour, with new technologies. This is necessary to reach a higher efficiency and process capability while maintaining a higher flexibility potential than fully automated systems.

Understanding the complex needs of automotive training at final assembly lines

Automobile final assembly operators must be highly skilled to succeed in a low automation environment where multiple variants must be assembled in quick succession. This paper presents formal user studies conducted at OPEL and VOLVO Group to identify assembly training needs and a subset of requirements; and to explore potential features of a hypothetical game-based virtual training system. Stakeholder analysis, timeline analysis, link analysis, Hierarchical Task Analysis and thematic content analysis were used to analyse the results of interviews with various stakeholders (17 and 28 participants at OPEL and VOLVO, respectively). The results show that there is a strong case for the implementation of virtual training for assembly tasks. However, it was also revealed that stakeholders would prefer to use a virtual training to complement, rather than replace, training on pre-series vehicles.

Dynamic Alignment Control Using Depth Imagery for Automated Wheel Assembly

This paper presents a novel method for dynamic alignment control using infrared light depth imagery to enable automated wheel loading operation for the trim and final automotive assembly line. A key requirement for automated wheel loading is to track the motion of the wheel hub and simultaneously identify the spatial positions and angular orientations of its alignment features in real-time on a moving vehicle body. This requirement is met in this work, where low-cost infrared depth-imaging devices like Microsoft Kinect™ and Asus Xtion™, vastly popular in the gaming industry, are used to track a moving wheel hub and recognise alignment features on both the wheel hub and the wheel in real time in a laboratory environment. Accurate control instructions are then computed to instruct the automation system to rotate the wheel to achieve precise alignment with the wheel hub and load the wheel at the right time. Experimental results demonstrate that the reproducibility error in alignment control satisfies the assembly tolerance of 2mm for the wheel loading operation, and thus the proposed method can be applied to automate wheel assembly on the trim and final automotive assembly line. The novelty of this work lies in its use of depth imaging for dynamic alignment control, which provides real-time spatial data in all 3 axes simultaneously as against the popularly reported RGB imaging techniques that are computationally more demanding, sensitive to ambient lighting and require the use of additional force sensors to obtain depth axis control data. This paper demonstrates the concept of a light-controlled factory where depth imaging using infrared light and depth image analysis is used to enable intelligent control in automation.

Adhesive Bonding of Attachments on Alternate Car Shell Surfaces in Automotive Final Assembly Lines

High-tech automotive manufacturers are highly focused on adapting modern production processes, lightweight design and high safety standards in order to satisfy the increasing concerns of modern societies regarding the environmental impact of automotives. This goal is further related to quality issues in current production lines and the final product itself, especially in order to satisfy highly demanding market safety standards. In this paper adhesive bonding of attachments on alternate automotive shell surfaces in final assembly lines is analyzed as a potential technique in volume production. Different process chain scenarios are examined depending on the paint type in order to achieve the required bond strength.

Inspector Robot – A New Collaborative Testing System Designed for the Automotive Final Assembly Line

The ‘water leak test’ in an automotive final assembly line is often a significant cost factor due to its labour intensive nature. This is particularly the case for premium car manufacturers as each vehicle is watered and manually inspected for leakage. This paper delivers an approach that optimises the efficiency and capability of the test process by using a new automated in-line inspection system whereby thermographic images are taken by a lightweight robot system and then processed to locate the leak. Such optimisation allows the collaboration of robots and manual labour which in turn enhances the capability of the process station.

Enhanced multi-Hoffmann heuristic for efficiently solving real-world assembly line balancing problems in automotive industry

In production systems of automobile manufacturers, multi-variant products are assembled on paced final assembly lines. The assignment of operations to workplaces and workers deter mines the productivity of the manufacturing process. In research, various exact and heuristic solution procedures have been developed for different versions of the so-called assembly line balancing problem.This paper shows that there is almost no solution procedure so far, which includes all line balancing restrictions occurring in real-world settings. We present a new general and flexible as well as fast heuristic procedure which meets all relevant requirements of line balancing in automotive industry. It is based on the successful multi-Hoffmann heuristic of Fleszar and Hindi [European Journal of Operational Research 145/3 (2003), 606–620] which is enhanced and extended to consider the required restrictions. Computational experiments show that the new procedure is competitive to state-of-the-art procedures even for specialized problems and able to compute high-quality feasible solutions in different test settings typical in real-world decision situations.

Self-reported work-related musculoskeletal injuries and isometric handgrip strength

Musculoskeletal injuries are common in car assembly workers, causing significant morbidity. There is evidence that increased muscle strength reduces musculoskeletal injury risk and that handgrip strength is a predictor of general muscle strength. Aims To investigate whether isometric handgrip strength (IHGS) is a predictor of increased musculoskeletal injury risk in automotive assembly workers. We measured IHGS in a cross-sectional survey of final assembly line workers in an automotive manufacturing plant. Weak handgrip was defined as two standard deviations below the normative mean value for age and gender. Self-reported musculoskeletal injury/accident data and recent musculoskeletal symptoms were recorded using a modified Nordic musculoskeletal questionnaire. Of 445 final assembly line workers, 206 (46%) participated. Sixty participants (29%) reported a musculoskeletal injury/accident at work in the preceding 5 years. Mean IHGS in this population was lower than international normative values. Odds ratios for self-reported injury (adjusted for gender and recent musculoskeletal symptoms) were 0.62 (95% CI 0.28-1.35) for left weak handgrip and 0.57 (95% CI 0.31-1.1) for right weak handgrip. In this study, weak handgrip did not predict increased risk of musculoskeletal injuries/accidents.

Virtual Verification of an Aircraft Final Assembly Line Industrialization: An Industrial Case

This communication describes the experience gained when implementing a Digital Manufacturing methodology to validate the industrial design of the AIRBUS A400M Final Assembly Line using commercial Product Lifecycle Management tools. The implementation project generated a remarkable innovation in the industrialization methods and tools used in AIRBUS Military, contributing to the A400M program success. The document presents: the background and reasons motivating the project, the context, the main barriers identified and the definition of a Final Assembly Line (FAL). An innovative concept of industrial Digital Mock-Up (iDMU) was coined, representing the interoperable grouping of product, processes and manufacturing resources data.

Conceptual Design of an Aircraft Final Assembly Line: A Case Study

During the conceptual design phase of a Final Assembly Line (FAL), the design solutions that will meet the functional and industrial requirements are defined, i.e.: the basic requirements of industrialization. During this phase, several alternatives are studied, and the most attractive in terms of performance and cost requirements is selected. As a result of the study of these alternatives, it is possible to define an early conceptual design of the assembly line and its basic parameters. The plant needs, long cycle jigs & tools or industrial means and human resources with the necessary skills can be determined in advance. This communication presents a case study focus on the FAL of the AIRBUS A400M.

Aircraft Final Assembly Line Balancing and Workload Smoothing: A Methodological Analysis

Assembly Line Balancing (ALB) comprises ordering of tasks among workstations to satisfy precedence constraints and objective functions. Due to the specific features of an aircraft, such approach is not fully suitable for the case of an aircraft Final Assembly Line (FAL). Where, the number of workstations relates to technological criteria rather than to a calculation aiming to minimize a specific parameter. Workload smoothing is addressed once the FAL configuration is defined. To improve current practices, a methodological approach was taken to address the conceptual modeling of an aircraft assembly line.

Optimally locating in-house logistics areas to facilitate JIT-supply of mixed-model assembly lines

Abstract In modern-day production systems, ever-rising product variety poses a great challenge for the internal logistics systems used to feed mixed-model assembly lines with the required parts. As an answer to this challenge many manufacturers especially from automobile industries have identified the supermarket-concept as a promising part feeding strategy to enable flexible small-lot deliveries at low cost. In this context, supermarkets are decentralized in-house logistics areas in the direct vicinity of the final assembly line, which serve as intermediary stores for parts. Small tow trains are loaded with material in a supermarket and deliver parts Just-in-Time to the stations lying on their fixed route. This paper discusses the general pros and cons of the supermarket-concept and treats the decision problem of determining the optimal number and placement of supermarkets on the shop floor. A mathematical model is proposed, an exact dynamic programming algorithm presented, and the validity of the proposed approach for practical purposes as well as the trade-off resulting from fixed installation and maintenance cost is investigated in a comprehensive computational study.

Détermination des stocks de sécurité dans une chaîne logistique-amont dédiée à une production de masse de produits très diversifiés

In an upstream supply chain dedicated to the mass production of customized products, many sources of production instability can be identified: the level and structure of the production of the final assembly line, the variability of lead times, the quality issues, packaging and loading constraints in transport, the anticipation of the demand, the synchronization of the flows of the components sent, received and produced. In the case of periodic replenishment policies, two different safety stocks are needed for every plant of the supply chain, which prevent from these various sources of fluctuations: a safety stock of produced components to face up to the demand of its downstream links and a safety stock of supplied components to face up to its production. The mobilized procedures must take into account the organizational framework of the exchanges of information and products. The relevance of the supply and production rules is based on the relevance of structural information broadcast along the supply chain.

4.3.3 Integrating Testability and Diagnosis methods into Airbus Systems Development Process

AbstractThis paper exposes methodologies, based on testing strategies (Start‐Small and Multiple‐Clue), able to support two main steps of Airbus systems development process: formal specification validation activities and systems testing activities on Airbus Final Assembly Line (FAL). The experiments show that these methods can quantify testing efforts, guide functional tests definition, facilitate detailed design coverage activities and ease fault location.

A Markovian model for the hybrid manufacturing planning and control method ‘Double Speed Single Production Line’

In this paper, the hybrid production planning & control method Double Speed Single Production Line (DSSPL) is presented, modelled and its performances evaluated and compared to classical Production Planning and Control methods (PPC). DSSPL combines JIT/kanban and Material Requirement Planning for the production of different classes of products (A- and B-items based on a market or customer oriented analysis) on one single production line. By the use of a Markovian birth–death queuing model of a single-stage, two-product production system, the performance and the behavior of the basic DSSPL concept are analyzed and compared to the classical MRP concepts. Its capability to cope with limited resources is illustrated with an industrial case study where DSSPL has been implemented to solve coordination problems between a plastic molding feeder shop and the final assembly line of a micromotor producer.

Culture against cohesion

Purpose – The purpose of this paper is to highlight employee diversity at the workplace level in a MNC, and consider its impact upon management attempts to promote a global corporate culture.Design/methodology/approach – The investigation took the form of an ethnographic participant‐observation study, which involved interviews and archival research plus a three‐month period when the lead researcher worked on the plant's final assembly line. This provided insights into the personal and psychological issues of individuals within the workforce, and an experiential dimension to the study which is difficult to replicate in other ways.Findings – The management approach to cultural and diversity issues worked both for and against the development of cohesion and improved employee relations. Managers sometimes ignored the real impact of local ethnic diversity, focusing instead on inter‐management conflicts, which contributed to employee morale and communication problems. But where diversity was recognised, more su...

3106 モジュール構造化による多品種少量生産対応検査プラットフォームの開発(OS3-1 生産システムの管理)

While manufacturing factories in Japan strengthen high-variety low-volume manufacturing more and more, there is a great demand of higher measures for it from manufacturing sites. The real bottleneck has been an inspection process at the final assembly line which decides manufacturing model and ability. We developed a platform which solves this bottleneck and inspects high-variety of products with cross-model and cross-group. Furthermore, the platform also has a capability to shorten the inspection time and control the quality of manufacturing line.