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Article
Publication date: 31 July 2009

Heping Chen, George Zhang, William Eakins and Thomas Fuhlbrigge

The purpose of this paper is to develop an intelligent robot assembly system for the moving production line. Moving production lines are widely used in many manufacturing…

Abstract

Purpose

The purpose of this paper is to develop an intelligent robot assembly system for the moving production line. Moving production lines are widely used in many manufacturing factories, including automotive and general industries. Industrial robots are hardly used to perform any tasks on the moving production lines. One of the main reasons is that it is difficult for conventional industrial robots to adjust to any sort of change. Therefore, more intelligent industrial robotic systems have to be developed to adopt the random motion of the moving production lines. This paper presents an intelligent robotics system that performs an assembly process while the object is moving, using synergic combination of visual servoing and force control technology.

Design/methodology/approach

The developed intelligent robotic system includes some rules to ensure the success of the assembly processes. Also visual servoing and force control are used to deal with the random motion of the moving objects. Since the objects on the moving production lines are moving with random speed, visual servoing is adopted to tracking the motion of the moving object. Force control is also integrated to control the motion of the robot and keep the robotic system compliant with the moving objects to avoid the damage of the whole system.

Findings

The developed intelligent robotic technology has been successfully implemented. The wheel loading process is used as example.

Research limitations/implications

Since the developed technology is based on the low‐level motion control, safety has to be considered. Currently, it is done by motion supervision.

Practical implications

The developed technology can be used to perform assemblies in the moving production lines. Since the developed platform is based on the synergic combination of visual servoing and force control technology, it can be used in other areas, such as seam tracking and seat loading, etc.

Originality/value

This paper provides a practical solution of performing assemblies on the moving production lines, which is not available on the current industrial robot market.

Details

Assembly Automation, vol. 29 no. 3
Type: Research Article
ISSN: 0144-5154

Keywords

Abstract

Details

Urban Dynamics and Growth: Advances in Urban Economics
Type: Book
ISBN: 978-0-44451-481-3

Abstract

Details

Transportation and Traffic Theory in the 21st Century
Type: Book
ISBN: 978-0-080-43926-6

Article
Publication date: 13 June 2016

Abhishek K. Singh, Anirban Lakshman and Amares Chattopadhyay

The response of moving load over a surface is a subject of investigation because of its possible applications in determining the strength of a structure. Recently, with the…

Abstract

Purpose

The response of moving load over a surface is a subject of investigation because of its possible applications in determining the strength of a structure. Recently, with the enlargement of high-speed train networks, concern has been expressed about the effects of moving loads on the track, embankment and nearby structures. Earth surface and artificial structure are not always regular in nature. Irregularities are also responsible for structural collapse of long bridge and highway of plateau area under the action of moving loads. The purpose of this paper is to investigate the influence of irregularity on dynamic response due to a moving shear load.

Design/methodology/approach

At first the authors developed the mathematical model for the problem which is comprised of equation of motion together with boundary conditions. Perturbation technique has been used to derive the stresses produced in an irregular orthotropic half-space (which is influenced by gravity) due to a moving shear load. MATLAB and MATHEMATICA softwares have been employed for numerical computation as well as graphical illustration.

Findings

In this paper the authors have discussed the stresses produced in an irregular gravitating orthotropic half-space due to a moving shear load. The expression for shear stress has been established in closed form. Substantial effects of depth, irregularity factor, maximum depth of irregularity and gravitational parameter on shear stress have been reported. These effects are also exhibited by means of graphical illustration and numerical computation for an orthotropic material T300/5208 graphite/epoxy which is broadly used in aircraft designing. Moreover, comparison made through meticulous examination for different types of irregularity, presence and absence of anisotropy and gravity are highlighted.

Practical implications

A number of classical fatigue failures occur in aircraft structures. The moving load responsible for such fatigue failure may occur during manufacturing process, servicing, etc. Apart from these the aircraft structures may also experience load because of environmental damages (such as lightning strike, overheat) and mechanical damages (like impact damage, overload/bearing failure). Therefore the present study is likely to find application in the field of construction of highways, airport runways and earthquake engineering.

Originality/value

To the best of the authors’ knowledge no problem related to moving load on irregular orthotropic half-space under influence of gravity has been attempted by any author till date. Furthermore comparative study for different types of irregularity, presence and absence of anisotropy and influence of gravity on the dynamic response of moving load are novel and major highlights of the present study.

Details

Multidiscipline Modeling in Materials and Structures, vol. 12 no. 1
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 2 January 2009

Ivica Kožar

The purpose of this paper is to investigate internal forces in bridges induced by moving vehicles and compare them to earthquake loading.

Abstract

Purpose

The purpose of this paper is to investigate internal forces in bridges induced by moving vehicles and compare them to earthquake loading.

Design/methodology/approach

Dynamic analysis of bridges is performed for moving support actions, for spectral method with Eurocode 8 parameters and for moving vehicle influence. Results from all three methods have been compared on two examples and conclusions have been made. Moving vehicle analysis could be based on the moving force and on the moving mass approach where the later one requires rather accurate knowledge of structural accelerations. It has been shown that the classical Newmark formulation produces accelerations of low accuracy and a novel impulse acceleration method has been devised.

Findings

It is found that the actions induced by the moving load could be comparable or larger than those caused by the earthquake on bridges whose mass is not too large in comparison to the vehicle mass.

Research limitations/implications

The developed method will be applied to a broader choice of examples and more reliable conclusions made.

Practical implications

There are bridges where it would be appropriate to perform moving vehicle dynamic analysis, in which case the vertical earthquake actions could be neglected in the analysis.

Originality/value

In order to assess actions from moving vehicles, Newmark method has been generalized in a novel way. Paper describes vector formulation of Newmark method that permits free mixing of integration parameters that could vary from node to node. The method is advantageous for moving load analysis where loading conditions of nodes change in time.

Details

Engineering Computations, vol. 26 no. 1/2
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 15 November 2018

Sultan Alamri

With the rapid development of the indoor spaces positioning technologies such as the radio-frequency identification (RFID), Bluetooth and WI-FI, the locations of indoor spatial…

Abstract

Purpose

With the rapid development of the indoor spaces positioning technologies such as the radio-frequency identification (RFID), Bluetooth and WI-FI, the locations of indoor spatial objects (static or moving) constitute an important foundation for a variety of applications. However, there are many challenges and limitations associated with the structuring and querying of spatial objects in indoor spaces. The purpose of this study is to address the current trends, limitations and future challenges associated with the structuring and querying of spatial objects in indoor spaces. Also it addresses the related features of indoor spaces such as indoor structures, positioning technologies and others.

Design/methodology/approach

In this paper, the author focuses on understanding the aspects and challenges of spatial database managements in indoor spaces. The author explains the differences between indoor spaces and outdoor spaces. Also examines the issues pertaining to indoor spaces positioning and the impact of different shapes and structures within these spaces. In addition, the author considers the varieties of spatial queries that relate specifically to indoor spaces.

Findings

Most of the research on data management in indoor spaces does not consider the issues and the challenges associated with indoor positioning such as the overlapping of Wi-Fi. The future trend of the indoor spaces includes included different shapes of indoors beside the current 2D indoor spaces on which the majority of the data structures and query processing for spatial objects have focused on. The diversities of the indoor environments features such as directed floors, multi-floors cases should be considered and studied. Furthermore, indoor environments include many special queries besides the common ones queries that used in outdoor spaces such as KNN, range and temporal queries. These special queries need to be considered in data management and querying of indoor environments.

Originality/value

To the best of the author’s knowledge, this paper successfully addresses the current trends, limitations and future challenges associated with the structuring and querying of spatial objects in indoor spaces.

Details

International Journal of Web Information Systems, vol. 14 no. 4
Type: Research Article
ISSN: 1744-0084

Keywords

Article
Publication date: 20 December 2023

Oskar Szulc, Piotr Doerffer, Pawel Flaszynski and Marianna Braza

This paper aims to describe a proposal for an innovative method of normal shock wave–turbulent boundary layer interaction (SBLI) and shock-induced separation control.

Abstract

Purpose

This paper aims to describe a proposal for an innovative method of normal shock wave–turbulent boundary layer interaction (SBLI) and shock-induced separation control.

Design/methodology/approach

The concept is based on the introduction of a tangentially moving wall upstream of the shock wave and in the interaction region. The SBLI control mechanism may be implemented as a closed belt floating on an air cushion, sliding over two cylinders and forming the outer skin of the suction side of the airfoil. The presented exploratory numerical study is conducted with SPARC solver (steady 2D RANS). The effect of the moving wall is presented for the NACA 0012 airfoil operating in transonic conditions.

Findings

To assess the accuracy of obtained solutions, validation of the computational model is demonstrated against the experimental data of Harris, Ladson & Hill and Mineck & Hartwich (NASA Langley). The comparison is conducted not only for the reference (impermeable) but also for the perforated (permeable) surface NACA 0012 airfoils. Subsequent numerical analysis of SBLI control by moving wall confirms that for the selected velocity ratios, the method is able to improve the shock-upstream boundary layer and counteract flow separation, significantly increasing the airfoil aerodynamic performance.

Originality/value

The moving wall concept as a means of normal shock wave–turbulent boundary layer interaction and shock-induced separation control has been investigated in detail for the first time. The study quantified the necessary operational requirements of such a system and practicable aerodynamic efficiency gains and simultaneously revealed the considerable potential of this promising idea, stimulating a new direction for future investigations regarding SBLI control.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 34 no. 7
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 1 March 1995

Roger Stuart

Describes research into managers′ experiences of significantorganizational change attempts. The research project was aimed atdeveloping frameworks which: describe, illuminate and…

5834

Abstract

Describes research into managers′ experiences of significant organizational change attempts. The research project was aimed at developing frameworks which: describe, illuminate and enable a better understanding of managers′ journeys through organizational change; serve as a template for bringing together the very diverse and fragmented literature relating to individuals experiencing change; highlight issues and pointers for the design and facilitation of effective organizational change initiatives. The first part describes the context, spirit, intentions, sample and methodology of the research. Also, reviews a broad range of literature which can inform our understanding of individuals in change. Propounds the need to open up the “real world” of organizational change, as perceived and experienced by managers, rather than any “ideal” view of how that world is desired or supposed to be. Presents and discusses research findings on the sensed and initiating “primary” triggers for change‐that is, the formal and communicated organizational change objectives; and the perceived and felt “secondary” triggers for change‐that is, the issues raised by, and the implications of, the organizational changes for individual managers. The second part presents a framework depicting the phases and components of managers′ journeys through organizational change. On the framework, the experience of managers can be located, in terms of their thoughts, feelings and behaviours, as the processes of change unfold. While each manager′s journey was found to be unique, the framework proved to be ubiquitous in enabling the mapping of all the managers′ journeys, and it also accommodates literature on phenomena as diverse as learning, personal transition, catastrophe and survival, trauma and stress, loss and “death”, and worry and grief. The findings emphasize the profoundness and deeply felt emotionality of many managers′ experiencing of change in organizations. Finally, identifies the outcomes of managers′ journeys through significant attempts at organizational change. Also presents the reported helping and hindering factors to those journeys. Implications of these findings are pursued, particularly in terms of the leadership and development roles and behaviours required, if the organization and its management are to move beyond simply requiring change towards actively facilitating its achievement.

Details

Personnel Review, vol. 24 no. 2
Type: Research Article
ISSN: 0048-3486

Keywords

Article
Publication date: 3 June 2021

Hakan Coşanay, Hakan F. Oztop and Fatih Selimefendigil

The purpose of this study is to perform computational analysis on the steady flow and heat transfer due to a slot nanojet impingement onto a heated moving body. The object is…

Abstract

Purpose

The purpose of this study is to perform computational analysis on the steady flow and heat transfer due to a slot nanojet impingement onto a heated moving body. The object is moving at constant speed and nanoparticle is included in the heat transfer fluid. The unsteady flow effects and interactions of multiple impinging jets are also considered.

Design/methodology/approach

The finite volume method was used as the solver in the numerical simulation. The movement of the hot body in the channel is also considered. Influence of various pertinent parameters such as Reynolds number, jet to target surface spacing and solid nanoparticle volume fraction on the convective heat transfer characteristics are numerically studied in the transient regime.

Findings

It is found that the flow field and heat transfer becomes very complicated due to the interaction of multiple impinging jets with the movement of the hot body in the channel. Higher heat transfer rates are achieved with higher values of Reynolds number while the inclusion of nanoparticles resulted in a small impact on flow friction. The middle jet was found to play an important role in the heat transfer behavior while jet and moving body temperatures become equal after t = 80.

Originality/value

Even though some studies exist for the application of jet impingement heat transfer for a moving plate, the configuration with a solid moving hot body on a moving belt under the impacts of unsteady flow effects and interactions of multiple impinging jets have never been considered. The results of the present study will be helpful in the design and optimization of various systems related to convective drying of products, metal processing industry, thermal management in electronic cooling and many other systems.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 32 no. 1
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 31 May 2023

Baran Bozyigit

This study aims to perform dynamic response analysis of damaged rigid-frame bridges under multiple moving loads using analytical based transfer matrix method (TMM). The effects of…

199

Abstract

Purpose

This study aims to perform dynamic response analysis of damaged rigid-frame bridges under multiple moving loads using analytical based transfer matrix method (TMM). The effects of crack depth, moving load velocity and damping on the dynamic response of the model are discussed. The dynamic amplifications are investigated for various damage scenarios in addition to displacement time-histories.

Design/methodology/approach

Timoshenko beam theory (TBT) and Rayleigh-Love bar theory (RLBT) are used for bending and axial vibrations, respectively. The cracks are modeled using rotational and extensional springs. The structure is simplified into an equivalent single degree of freedom (SDOF) system using exact mode shapes to perform forced vibration analysis according to moving load convoy.

Findings

The results are compared to experimental data from literature for different damaged beam under moving load scenarios where a good agreement is observed. The proposed approach is also verified using the results from previous studies for free vibration analysis of cracked frames as well as dynamic response of cracked beams subjected to moving load. The importance of using TBT and RLBT instead of Euler–Bernoulli beam theory (EBT) and classical bar theory (CBT) is revealed. The results show that peak dynamic response at mid-span of the beam is more sensitive to crack length when compared to moving load velocity and damping properties.

Originality/value

The combination of TMM and modal superposition is presented for dynamic response analysis of damaged rigid-frame bridges subjected to moving convoy loading. The effectiveness of transfer matrix formulations for the free vibration analysis of this model shows that proposed approach may be extended to free and forced vibration analysis of more complicated structures such as rigid-frame bridges supported by piles and having multiple cracks.

Details

Engineering Computations, vol. 40 no. 4
Type: Research Article
ISSN: 0264-4401

Keywords

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