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1 – 10 of over 36000Jianping Ma, Lianfa Yang, Yulin He and Jian Guo
This paper aims to study frictional characteristics of thin-walled tubes in the liquid impact forming (LIF) process.
Abstract
Purpose
This paper aims to study frictional characteristics of thin-walled tubes in the liquid impact forming (LIF) process.
Design/methodology/approach
LIF experiments under various impacting velocities were performed on SUS304 stainless steel tubes with various guiding lengths on a custom-designed measurement system to investigate the effects of impacting velocity and guiding length on the coefficient of friction (COF) in the guiding zone.
Findings
The results indicate that the COF changes dynamically in the guiding zone and decreases with the deformation process. The reduction range of the COF is wider in LIF than in both the conventional and pulsating hydroforming (THF), which may be contributed to the impacting velocities in a short time. Moreover, the COF decreases faster in the first half of the LIF process than in the second half. Under different impacting velocities and guiding lengths, the decreasing rate of the COF in the first half is more sensitive and obvious than that in the second half.
Originality/value
A method for determining the COF in the guiding zone in LIF is proposed and the frictional characteristics in LIF are studied. Comparing the COF of tubes in conventional THF, pulsating THF and the LIF process is valuable for improving and predicting the tubular formability in various hydraulic environments for industrial production.
Peer review
The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-07-2019-0269
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Abstract
Fraunhofer Institute for Factory Operation and Automation (IFF). SIRIUS is a climbing robot meant for any vertical surface, regardless of the angle. The robot can be outfitted with tools to perform a variety of service‐sector tasks such as façade cleaning, building and ship coating, ship welding, inspection work on tanks, and so on. It is a modular system, and the robot can be adapted to almost any surface, independent of the surface material or obstacles. The robot stays attached to the surface via suction cup feet or magnetic grippers, and moves vertically on four linear guides that are coupled in two pairs. The new kinematics of the robot allow it to walk continuously in all directions. The robot overcomes obstacles by sensing their position and generating the necessary step length in order to maximize the number of suction cups attached to the surface while walking over the obstacle.
S. Sahoo, S. Saha Ray and S. Das
In this paper, the formulation and analytic solutions for fractional continuously variable order dynamic models, namely, fractional continuously mass-spring damper (continuously…
Abstract
Purpose
In this paper, the formulation and analytic solutions for fractional continuously variable order dynamic models, namely, fractional continuously mass-spring damper (continuously variable fractional order) systems, have been presented. The authors will demonstrate via two cases where the frictional damping given by fractional derivative, the order of which varies continuously – while the mass moves in a guide. Here, the continuously changing nature of the fractional-order derivative for dynamic systems has been studied for the first time. The solutions of the fractional continuously variable order mass-spring damper systems have been presented here by using a successive recursive method, and the closed form of the solutions has been obtained. By using graphical plots, the nature of the solutions has been discussed for the different cases of continuously variable fractional order of damping force for oscillator. The purpose of the paper is to formulate the continuously variable order mass-spring damper systems and find their analytical solutions by successive recursion method.
Design/methodology/approach
The authors have used the viscoelastic and viscous – viscoelastic dampers for describing the damping nature of the oscillating systems, where the order of the fractional derivative varies continuously.
Findings
By using the successive recursive method, here, the authors find the solution of the fractional continuously variable order mass-spring damper systems, and then obtain close-form solutions. The authors then present and discuss the solutions obtained in the cases with the continuously variable order of damping for an oscillator through graphical plots.
Originality/value
Formulation of fractional continuously variable order dynamic models has been described. Fractional continuous variable order mass-spring damper systems have been analysed. A new approach to find solutions of the aforementioned dynamic models has been established. Viscoelastic and viscous – viscoelastic dampers are described. The discussed damping nature of the oscillating systems has not been studied yet.
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Chad Perry, David Carson and Audrey Gilmore
Writing articles is a core activity in an academic's career. The aim of this article is to show prospective writers of an article in EJM how to go about getting published. It…
Abstract
Writing articles is a core activity in an academic's career. The aim of this article is to show prospective writers of an article in EJM how to go about getting published. It emphasises that an EJM article is a part of a conversation with the editors, reviewers and readers. First, the concept of joining this conversation is established. Then targeting a journal and other aspects of planning with co‐authors are noted, before an article's structure and style are described. Drafting, submitting and revising the article, and starting again if it is rejected, conclude the paper. This article should be useful for those academics who are not publishing enough, and for doctoral candidates and their supervisors.
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Ignacijo Bilus and Andrej Predin
This study aims to present the analysis of methods for cavitaion surge obstruction in water pump systems with particular focus on the two different inlet geometry configurations.
Abstract
Purpose
This study aims to present the analysis of methods for cavitaion surge obstruction in water pump systems with particular focus on the two different inlet geometry configurations.
Design/methodology/approach
A cavitating flow field was simulated by RANS based computational fluid dynamics (CFD) program for different pump configurations operating in the unstable cavitation regime, inducing surging process. Numerical simulation results were compared to visualization and measurements results.
Findings
Presented results show that a hydro dynamically induced surging regime could be limited and further advantages regarding operating characteristics of radial pumps could be achieved with presented geometry modifications.
Originality/value
This study provides insight into complicated transient cavitation flow patterns in conventional centrifugal pumps and introduces effective geometry optimization ideas useful to researchers and engineers in the area of fluid dynamics and hydromachinery.
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Nour El-Hoda Khalifeh, Rudy Youssef, Farah Fadel, Roy Khalil, Elie Shammas, Naseem Daher, Imad H. Elhajj, Thomas Irrenhauser, Michael N. Niedermeier and Christian Poss
The purpose of this paper is to detail the design and prototyping of a smart automation solution for de-strapping plastic bonding straps on shipping pallets, which are loaded with…
Abstract
Purpose
The purpose of this paper is to detail the design and prototyping of a smart automation solution for de-strapping plastic bonding straps on shipping pallets, which are loaded with multiple containers secured by a top-cover as they move on a conveyor belt.
Design/methodology/approach
The adopted design methodology to have the system perform its function entails using the least number of sensors and actuators to arrive at an economic solution from a system design viewpoint. Two prototypes of the robotic structure are designed and built, one in a research laboratory and another in an industrial plant, to perform localized cutting and grabbing of the plastic straps, with the help of a custom-designed passive localizing structure. The proposed structure is engineered to locate the plastic straps using one degree of freedom (DOF) only. An additional strap removal mechanism is designed to collect the straps and prevent them from interfering with the conveyor.
Findings
The functionality of the system is validated by performing full-process tests on the developed prototypes in a laboratory setting and under real-life operating conditions at BMW Group facilities. Testing showed that the proposed localization system meets the specified requirements and can be generalized and adapted to other industrial processes with similar requirements.
Practical implications
The proposed automated system for de-strapping pallets can be deployed in assembly or manufacturing facilities that receive parts in standard shipping pallets that are used worldwide.
Originality/value
To the best of the authors’ knowledge, this is the first mechanically smart system that is used for the automated removal of straps from shipping pallets used in assembly facilities. The two main novelties of the proposed design are the robustness of the strap localization without the need for computer vision and a large number of DOF, and the critical placement and choice of the cutting and gripping tools to minimize the number of needed actuators.
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Radislav Potyrailo and Sergei Golubkov
Achievements in guided wave optics have had a great influence on many areas of technology for several years. Fibre optic communication links, sensors for various parameters…
Abstract
Achievements in guided wave optics have had a great influence on many areas of technology for several years. Fibre optic communication links, sensors for various parameters, recently developed distributed temperature sensors, integrated optical switches, etc. are all applications that are commercially available. The field of analytical chemistry is no exception in this growing technology. In order to compete with well‐established chemical‐sensing instrumentation, optical waveguide chemical sensors (OWCSs) must show all the qualities of such instrumentation. OWCSs combine well‐known features of sensors, based on waveguide optics, with optical methods of chemical analysis and offer advantages over other types of chemical sensor. OWCSs are electrically passive, corrosion‐resistant, can respond to analytes for which other chemical sensors are not available, and referencing can be carried out optically. They allow multicomponent measurements at several wavelengths, have a common technology for fabrication of sensors for different chemical and physical parameters and are easily compatible with telemetry etc. Further, only OWCSs are capable of distributed sensing. However, interference from ambient light, temperature, long‐term instability, relatively slow response time, and limited dynamic range may be a problem for some types of OWCS. These disadvantages can be considerably reduced using various methods.
This paper presents a new method for deploying RoboCrane‐type cable robots, without the need for fixed rigid cable support points. That is, the system provides its own deployable…
Abstract
Purpose
This paper presents a new method for deploying RoboCrane‐type cable robots, without the need for fixed rigid cable support points. That is, the system provides its own deployable mobile overhead support points.
Design/methodology/approach
This paper presents a new RoboCrane support concept based on rigid members, cable actuation, and cable suspension. It is self‐contained and provides mobility for the required six overhead cable connections, thus extending the workspace of the existing RoboCrane. The paper presents the RoboCrane support concept overview, followed by kinematics and statics analysis, plus a case study of a specific design.
Findings
Design for kinematic horizontality, workspace, and statics are competing so the designer must make tradeoffs for the best system performance according to specific design needs.
Research limitations/implications
Since the support system plus RoboCrane are both cable‐suspended robots, there are limitations in the pseudostatic workspace, i.e. since the cables can only exert tension and cannot push, the motion range is limited.
Practical implications
Specific system design and deployment is still remaining work – practical issues such as outriggers for moment and tipping resistance, easy portability, control of the mast from the ground, and safety must be solved in the future.
Originality/value
Enables RoboCrane applications in many more arenas, such as automated construction, where rigid overhead cable support points are simply unavailable.
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S. Udhayakumar, P.V. Mohanram, S. Yeshwanth, Manas Ranjan Biswal and A. Sabareeswaran
The purpose of this paper is to discuss a linear vibratory part feeder for handling brake liners, typical sector-shaped components. Part feeders have been used in the industries…
Abstract
Purpose
The purpose of this paper is to discuss a linear vibratory part feeder for handling brake liners, typical sector-shaped components. Part feeders have been used in the industries for a long time to present the parts in a desired orientation. Berretty et al. (1999) discussed a class of mechanical filters that are capable of removing polygonal sections from the track of the feeder which are referred to as traps. The traps eliminate or reorient the parts until they reach the final desired orientation. A part feeder was developed using traps, to reorient the sector-shaped part to desired orientation. The desired orientation was the most probable natural resting orientation. The trap was mounted on a linear vibratory feeder. The adaptive part feeder developed was capable of identifying the size of the incoming part and adjust the trap to accommodate that. This set-up eliminates the use of different traps for different-sized sector-shaped parts and wastage of productive time in changing the traps for different sizes. A regression model was developed to predict the conveying velocity of part on the feeder.
Design/methodology/approach
A part feeder was developed using traps, to reorient the sector-shaped part to desired orientation. Acrylic material was found to be suitable for trap compared to aluminium. The adaptive part feeder developed was capable of identifying the size of the incoming part using proximity sensors. Depending on the size of the incoming part, the track width was adjusted dynamically with the help of a stepper motor, rack and pinion arrangement. A regression model was developed to predict the conveying velocity.
Findings
Typical brake liners in the size range of 40-60 mm (radius) were considered for developing the adaptive part feeder. Based on performance studies, the acrylic trap was found better than aluminium traps. The appropriate frequency and amplitude of vibration for maximum conveying velocity of the adaptive part feeder were found experimentally. Regression equation was developed to determine the conveying velocity based on input frequency and amplitude. The regression results were found to be in close agreement with the experimental results.
Research limitations/implications
The developed part feeder is suitable for handling sector-shaped parts only.
Originality/value
This paper demonstrates an inexpensive adaptive part feeding device for handling sector-shaped parts which can be extended for handling other asymmetric parts also.
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This paper is intended to provide a guidebook for organizational futurists in building a foresight function inside today’s organizations by suggesting ten questions that ought to…
Abstract
This paper is intended to provide a guidebook for organizational futurists in building a foresight function inside today’s organizations by suggesting ten questions that ought to be answered. It addresses how to start from a blank page, but can also offer help to those who have already established a function by suggesting additional questions to think about. It is intended to give auditees a sense of the key issues and challenges they will face. Managers may also find this audit useful in giving a sense of what an organizational futures function can deliver and the skills required of a prospective organizational futurist. A key assumption here is that while there is a growing demand for organizational futurists, the role is evolving to more of a broker function than the building of a staff function more typical of the past.
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