1,720,961 research outputs found
A Framework Development for the Application of Lean Manufacturing and Automation to Warehouses in Developing Countries
No full textL'abstract è presente nell'allegato / the abstract is in the attachmen
Feasibility Study URe5 Collaborative Robot at Engine Piston Assembly Station
No full textThis paper aims to answer the question of the
applicability of collaborative robots (cobots) that are suitable
for engine piston assembly applications. To define the possible
application and methods, a case study is conducted where the
integration of collaborative robots is assessed and compared to
the current state, which is performed manually. The engine
piston assembly station was mapped using the hierarchical task
analysis (HTA) method to statistically identify the effective time
of each value-added task within the assembly operation. Then a
new station layout was recreated with a collaborative robot in
RoboDK simulation software to measure how much time is
needed to complete the robot task. The rest is tested in
laboratory conditions with the URe5 collaborative robot to
compare the mean effective process times of manual, hybrid,
and simulation operations
Semi-automated Assembly Process Using Arm Manipulator
Get PDFToday’s global market requires the ability to adapt to high production volumes, product variety, increase product quality and decrease production time to market for the assembly system. The increase of demand for the product quality and variety is 2P product related requirements, meanwhile increase of demand for the production volume and decrease production time to market time is 2P production related requirements. This paper defines these requirements as “2+2P” a main research problem of the assembly system. As well as, the future assembly systems need to fulfill capability and capacity flexibility of the market. The empirical studies have documented that human is the most flexible element of the manufacturing systems and they are responsible for capability flexibility, while machines are good at repetitive tasks and they enhance the capacity flexibility. Therefore, the aim of this paper is to examine the increase of human centered automation levels in manual assembly system, with the integration of ARM manipulator using System Modeling Language. In this study, an assembly, conventionally having a lower degree of automation, is investigated for human and arm interaction for productivity gains keeping constant flexibility. The integration methodology is based on System Modeling Language (SysML), for specifying analyzing, designing and verifying hybrid system. The station layout, tooling design and manipulator programming are elaborated using digital Solid works and Process Simulator tools. The motivations as well as the benefits derived from the employment of the arm manipulator into industrial case are discussed. The proposed methodology allows decrease of cycle time from 900 seconds to around 470 seconds, increase productivity, ergonomics of the assembly cell and increases the product quality by reducing human involvement by 23%
AS/RS travel time with horizontal deployment in class-based storage areas: a new formula
No full textThe enhancement of warehouse processes is pivotal in internal logistics activities and it is a lever of competitive advantage for companies that are operating in more turbulent business environment. Thus, this paper proposes a model for the accurate computation of travel time of automated warehouse systems under different configurations. The model is based on a simulation approach that is run with different levels of Input/Output (I/O) points, different shape factor values and rotational flows. The outcomes of the simulation are then analysed using regression analysis. The results obtained prove to be very accurate for a reliable calculation of travel times. Therefore, the proposed formula can be considered as an effective support for an accurate estimation of the travel time for a variety of automated warehouse configurations. The proposed work might be also supporting future studies focused on the warehouse design under different storage space shapes and operational conditions
Implementation of Lean Manufacturing tools in emerging countries: evidence from Uzbek SMEs
Get PDFIt is known that Lean Manufacturing (LM) practices play a significant role in achieving lower costs, higher flexibility, and efficiency in production processes, in order to fit the requirement of today’s dynamic customer demand. A lot of literature contributions deal with the application of Lean in developed countries. However, few studies have been focused on integrating various Lean tools to optimize manufacturing processes in developing countries. In particular, a limited number of case studies address manufacturing in Small and Medium Enterprises (SMEs) in Central Asian countries. Thus, the purpose of this work is to investigate through a case study how LM can enhance the operational efficiency of an Uzbek aluminium profiles manufacturer. The proposed combination of different LM techniques, such as Value Stream Mapping (VSM), 5 W +1 H, and 5S, improved the overall performance of the production process at issue. Wasted time was reduced to 2% and 8% in press and painting shops respectively. Additionally, the total daily production rate was increased up to 30.1 t/day. LM application to emerging countries’ SMEs improves production effectiveness and helps to achieve higher levels of production standards, which leads to an increase export capability and market share in the international context
Comprehensive assessment methodology of the competitiveness of freight transport services
No full textThe strategic goal of development of the transport system is to meet the needs of socially oriented development of the economy and society in competitive high- quality transport services. The method of determining the competitiveness of freight transport services developed by the authors is based on the system of indicators for assessing the competitiveness of freight transport services and includes natural and cost indicators that collectively reflect the competitiveness of each operator's services for railway, airway and roadway networks
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
AS/R system travel time in class-based storage with different input-output point levels: a proposed formula
Get PDFPurpose-This paper aims to propose a simulation model integrated with an empirical regression analysis to provide a new mathematical formulation for automated storage and retrieval system (AS/RS) travel time estimation under class-based storage and different input/output (I/O) point vertical levels.
Design/methodology/approach – A simulation approach is adopted to compute the travel time under different warehouse scenarios. Simulation runs with several I/O point levels and multiple shape factor values.
Findings – The proposed model is extremely precise for both single command (SC) and dual command (DC) cycles and very well fitted for a reliable computation of travel times.
Research limitations/implications – The proposed mathematical formulation for estimating the AS/ RS travel time advances widely applied methodologies existing in literature. As well as, it provides a practical implication by supporting faster and more accurate travel time computations for both SC and DC cycles. However, the regression analysis is conducted based on simulated data and can be refined by numerical values coming from real warehouses.
Originality/value– This work provides a new simulation model and a refined mathematical equation to estimate AS/RS travel time
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