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1 – 10 of over 58000Tim Giesen, Erwin Bürk, Christian Fischmann, Wolfgang Gauchel, Manfred Zindl and Alexander Verl
The purpose of this paper is to provide a technical review of a new Bernoulli gripper development using computed fluid dynamics (CFD) modeling, and also to outline an appropriate…
Abstract
Purpose
The purpose of this paper is to provide a technical review of a new Bernoulli gripper development using computed fluid dynamics (CFD) modeling, and also to outline an appropriate independent testing method for validating and evaluating process capability in terms of automated thin wafer handling. The investigation has been carried out by a collaborative way of Festo and Fraunhofer IPA as a connecting link between applied research and industrial needs.
Design/methodology/approach
Following an introduction, the paper first describes the basic development and fundamental principles of a gripper based on Bernoulli's law. The gripper was dimensioned and designed with the aid of CFD methods. The performance of the hardware was tested using extreme parameter settings while gripping thin, fragile workpieces. The performance of the gripper was tested from the aspects of shortest cycle times, positioning accuracy and air consumption and followed a manufacturer-independent design of experiments. A characterization of the gripping force generated during horizontal and vertical tension tests provides conclusive closed loop validation with regard to the gripper's air flow in the initial CFD model.
Findings
Photovoltaic (PV) grippers are challenging components since the handling objects, 200-120 μm thin crystalline silicon wafers with an area of 156×156 mm, are one of the most fragile parts as far as required handling speeds and cycle times are concerned.
Originality/value
The paper provides a detailed technical review of a CFD application used in the development of a Bernoulli gripper and also describes a method for testing and evaluating PV grippers for industrial scale applications. The article presents the results of a close cooperation regarding an industrial development (Festo AG & Co. KG) and independent applied research (Fraunhofer IPA) for advanced product benchmarking and validation in a relatively young but dynamic and increasingly-automated PV industry.
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Louwrens J. Butler and Glen Bright
This paper aims to examine the structure of the control strategy that is being deployed on the control of the mobile materials handling platform, from the higher level onboard…
Abstract
Purpose
This paper aims to examine the structure of the control strategy that is being deployed on the control of the mobile materials handling platform, from the higher level onboard interface software to the low‐level control system that is tasked with the dynamic stability of the platform.
Design/methodology/approach
The application of the principle of the inverted pendulum in mobile robotics has only recently been made possible by advances in the technology of electronics. A mobile materials handling platform has been designed and built for use in manufacturing systems of the future. The principle of the inverted pendulum has been incorporated into the design. This means that the platform is able to maintain dynamic stability during specific periods of operation. The mechatronic engineering approach was adopted in the design of the platform, which produced an integrated embedded system.
Findings
Open source software being implemented onboard the platform for interfacing between the platform and remote client computers is found to be easily customisable according to the requirements of one's application. A solution to the problem of nonholonomic motion constraints that concern any differential drive mobile robot was found in a nonlinear state transformation algorithm. The algorithm was implemented on an intermediate level between the interface software and the low‐level control system. The low‐level feedback control system was designed using a linear quadratic regulator design method. Simulations of this control system showed that it was robust enough to reject predetermined disturbances in system characteristics.
Originality/value
The application of a mobile platform specifically designed for materials handling based on the principle of the inverted pendulum has not been attempted to date.
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Antonio C. Caputo and Pacifico M. Pelagagge
Assembly systems require uninterrupted components' availability to feed workstations. This paper aims to propose a methodology to help managers in evaluating and selecting the…
Abstract
Purpose
Assembly systems require uninterrupted components' availability to feed workstations. This paper aims to propose a methodology to help managers in evaluating and selecting the most suitable policy for materials delivery to the shop floor. The analysis focuses on three basic policies, namely kitting, just in time kanban‐based continuous supply and line storage, even including class‐based hybrid policies.
Design/methodology/approach
Descriptive models are developed to design components' delivery systems and to compute their performances. Empirical criteria are utilized to associate specific policies to components classes in order to implement customized hybrid line feeding policies. A case study is then included to exemplify the method application and to show its capabilities as a decision making tool.
Findings
Hybrid feeding policies may be preferable to a single feeding policy common to all components. This is shown in a representative case study. However, in general there is a priori superior method and only a comparison of alternative feeding policies based on objective performance measures can determine the best approach in specific industrial applications.
Research limitations/implications
The methodology is aimed at preliminary sizing and selection of alternative line feeding systems in deterministic environments. It is not intended for detailed performance analysis of assembly systems.
Practical implications
Production managers are given quantitative decision tools to properly select the components' delivery method at an early decision stage. This allows trade‐offs between alternatives to be explored in order to deploy customized feeding policies differentiated on components basis to better fit specific company requirements.
Originality/value
The paper extends previous descriptive models for line feeding systems and includes the possibility of hybrid policies.
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An orientation system incorporating a low power He‐Ne laser system is described. In one application grub screws were fed at rates in excess of 100 per minute
P.G. Leaney and Gunter Wittenberg
The product design that is best for function, for manufacturing, for assembling and for servicing results in the best product. Such a design is an ideal so difficult to achieve…
Abstract
The product design that is best for function, for manufacturing, for assembling and for servicing results in the best product. Such a design is an ideal so difficult to achieve that it has to be tackled in stages, which ultimately have to be successfully integrated. The stages of Design for Manufacture (DFM) and Design for Assembly (DFA) combine towards that integration in the form of Design for Manufacture and Assembly (DFMA). Some broad guidelines for DFMA are given in Table I.
This paper aims to illustrate the growing role of robots in the electronics industries.
Abstract
Purpose
This paper aims to illustrate the growing role of robots in the electronics industries.
Design/methodology/approach
Following a short introduction, this paper discusses robotic applications and products in three sectors of the electronics industry: semiconductor processing, printed circuit manufacture and electronic product assembly. Finally, conclusions are drawn.
Findings
The major application in semiconductor manufacture is the handling of silicon wafers during both front- and back-end processes and products include cleanroom certified multi-axis robotic arms, some mounted on mobile platforms, and automated guided vehicles. Applications in printed circuit board production include component handling and insertion, soldering, inspection, testing and packing. These exploit Cartesian, SCARA and six-axis articulated robots and cobots play an important role where automated and manual processes operate in close proximity. Electronic product assembly applications include part handling, soldering, bonding and sealing, screw driving, test and inspection and packaging. Cobots offer the benefits of a small footprint which allows deployment in the often limited space and use in proximity to humans. As yet, robotic assembly of complex electronic products such as smartphones and computers has not been realised for technical reasons.
Originality/value
This study provides a detailed review of robotic products and applications in three key sectors of the electronics industries.
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Nirosh Jayaweera, Phil Webb and Craig Johnson
The purpose of this paper is to describe the measurement‐assisted assembly of aero‐engine fabricated components and evaluate its capability.
Abstract
Purpose
The purpose of this paper is to describe the measurement‐assisted assembly of aero‐engine fabricated components and evaluate its capability.
Design/methodology/approach
The system described in this paper uses in‐process measurement sensors to determine the component's exact location prior to the assembly operation. The core of the system is a set of algorithms capable of best fitting measurement data to find optimal assembly of components.
Findings
The paper demonstrates that with a combination of non‐contact metrology systems and mathematical processing, standard industrial robot can be used to assemble fabricated components. Scanning parts after it has been picked up was very effective as it compensates for possible components deformation during previous manufacturing processes and robot handling errors.
Originality/value
The paper introduces techniques for compensating the deformation that occurs in aero‐engine fabricated components and potential component handling errors. The developed system reduces the reliance on part holding fixtures and instead uses a laser‐guided robot. This ensures that the system is highly flexible and re‐configurable.
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Abstract
Details
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German companies tended to dominate the Industrial Handling Exhibition in Zurich last February. Brian Rooks reports on a show that has gained a reputation for displaying advanced…
Pierre Lambert and Alain Delchambre
This work aimed at studying the use of capillary forces as a gripping principle in the handling of sub‐millimetric sized components. The goal was to present the results as design…
Abstract
Purpose
This work aimed at studying the use of capillary forces as a gripping principle in the handling of sub‐millimetric sized components. The goal was to present the results as design rules of so‐called capillary grippers.
Design/methodology/approach
Each parameter (surrounding environment, materials, volume of liquid, separation distance, gripper geometry and gripper size, relative orientation of the gripper with respect to the component) has been quantified, either numerically or experimentally. In some validation cases, both means have been used.
Findings
The capillary forces can be modified between a maximum Fmax and a minimum Fmin so that a component with any mass m between Fmin/g and Fmax/g can be picked up and released.
Research limitations/implications
By comparison with some existing capillary grippers prototypes, this work is only a theoretical and experimental study. Nevertheless, its originality lies in the exhaustive study and quantification of all parameters so that most of the capillary grippers of the literature can be explained or improved with these results.
Practical implications
The main implication of the capillary gripping is that it provides an alternative to existing gripping principles (vacuum grippers, tweezers). This principle is strong enough (a few mN) and well adapted to pick up components with only one free accessible surface. The scaling laws are the most favorable (F∼L). It provides a “soft” picking, avoiding high contact forces.
Originality/value
The originality lies in the exhaustive quantification of the role of each parameter. These results can be used by researchers and designers.
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