The gas sensors fabricated by using conducting polymers such as polyaniline (PAni), polypyrrole (PPy) and poly (3,4-ethylenedioxythiophene) (PEDOT) as the active layers have been reviewed. This review discusses the sensing mechanism and configurations of the sensors. The factors that affect the performances of the gas sensors are also addressed. The disadvantages of the sensors and a brief prospect in this research field are discussed at the end of the review.

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Gas Sensors Based on Conducting Polymers

Welding Metallurgy of

Wire-feed additive manufacturing (AM) is a promising alternative to traditional subtractive manufacturing for fabricating large expensive metal components with complex geometry. The current research focus on wire-feed AM is trying to produce complex-shaped functional metal components with good geometry accuracy, surface finish and material property to meet the demanding requirements from aerospace, automotive and rapid tooling industry. Wire-feed AM processes generally involve high residual stresses and distortions due to the excessive heat input and high deposition rate. The influences of process conditions, such as energy input, wire-feed rate, welding speed, deposition pattern and deposition sequences, etc., on thermal history and resultant residual stresses of AM-processed components needs to be further understood. In addition, poor accuracy and surface finish of the process limit the applications of wire-feed AM technology. In this paper, after an introduction of various wire-feed AM technologies and its characteristics, an in depth review of various process aspects of wire-feed AM, including quality and accuracy of wire-feed AM processed components, will be presented. The overall objective is to identify the current challenges for wire-feed AM as well as point out the future research direction.

Wire-feed additive manufacturing of metal components: technologies, developments and future interests

A method of fabricating a fully dense, three dimensional object by direct laser sintering is disclosed (flow chart). In a chamber (evacuated) with a partial pressure atmosphere, a degased powder layer is dispensed over a target surface and a beam of directed energy melts metallic powder in order to form a solid layer cross section. Another layer of powder is deposited and melted, along with a portion of the previous layer. The energy beam typically is in the form of a laser, scanning along a path resembling a parametric curve or another, arbitrary piecewise parametric curve (vector scan). In another embodiment, the previous layer is not remelted, thus creating an oxide film that acts as a clean stop to prevent unwanted downward growth.

Direct selective laser sintering of metals

Survey on human–robot collaboration in industrial settings: Safety, intuitive interfaces and applications

A review of the wire arc additive manufacturing of metals: properties, defects and quality improvement

Although an automated flexible production cell is an intriguing prospect for small to median enterprises (SMEs) in current global market conditions, the complexity of programming remains one of the major hurdles preventing automation using industrial robots for SMEs. This paper provides a comprehensive review of the recent research progresses on the programming methods for industrial robots, including online programming, offline programming (OLP), and programming using Augmented Reality (AR). With the development of more powerful 3D CAD/PLM software, computer vision, sensor technology, etc. new programming methods suitable for SMEs are expected to grow in years to come.

/pdf/review-recent-progress-on-programming-methods-for-industrial-328gr3a9o6.pdf

Review: Recent progress on programming methods for industrial robots

Although an automated flexible production cell is an intriguing prospect for small to median enterprises (SMEs) in current global market conditions, the complexity of programming remains one of the major hurdles preventing automation using industrial robots for SMEs. This paper provides a comprehensive review of the recent research progresses on the programming methods for industrial robots, including online programming, offline programming (OLP), and programming using Augmented Reality (AR). With the development of more powerful 3D CAD/PLM software, computer vision, sensor technology, etc, new programming methods suitable for SMEs are expected to grow in years to come.

Recent progress on programming methods for industrial robots

An introduction to welding processes welding process development trends welding power source technology filler materials for arc welding gases for advanced welding processes advanced gas tungsten arc welding high energy density processes narrow gap welding techniques monitoring and control of welding processes welding automation and robotics.

John Norrish

Papers

A review of the wire arc additive manufacturing of metals: properties, defects and quality improvement

Review: Recent progress on programming methods for industrial robots

Recent progress on programming methods for industrial robots

Advanced Welding Processes

Artificial neural networks for modelling the mechanical properties of steels in various applications