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This paper gives a brief overview of requirements within the aerospace market sector for which optical sensors are of potential benefit, and goes on to describe sensors currently under development at Lucas Electrical and Electronic Systems which are primarily intended to meet some of these requirements. These sensors, based on the combination of silicon micromachining and optical sensing technologies, are sufficiently robust to provide the capability of directly measuring on‐engine parameters such as pressure and temperature. In association with FADEC‐mounted interface units, to which the sensor heads are coupled via optical fibre links, the sensors have the potential to provide measurement data for a number of aero‐engine control requirements.

Two-level support with Level 1 consisting of a set of beams and Level 2 consisting of a tree-like structure is an efficient support structure for extrusion-based additive manufacturing (EBAM). However, the literature for finding a slim two-level support is rare. The purpose of this paper is to design a lightweight two-level support structure for EBAM.

To efficiently solve the problem, the lightweight design problem is split into two subproblems: finding a slim Level 1 support and a slim Level 2 support. To solve these two subproblems, this paper develops three efficient metaheuristic algorithms, i.e. genetic algorithm (GA), genetic programming (GP) and particle swarm optimization (PSO). They are problem-independent and are powerful in global search. For the first subproblem, considering the path direction is a critical factor influencing the layout of Level 1 support, this paper solves it by splitting the overhang region into a set of subregions, and determining the path direction (vertical or horizontal) in each subregion using GA. For the second subproblem, a hybrid of two metaheuristic algorithms is proposed: the GP manipulates the topologies of the tree support, while the PSO optimizes the position of nodes and the diameter of tree branches. In particular, each chromosome is encoded as a single virtual tree for GP to make it easy to manipulate Crossover and Mutation. Furthermore, a local strategy of geometric search is designed to help the hybrid algorithm reach a better result.

Simulation results show that the proposed method is preferred over the existing method: it saves the materials of the two-level support up to 26.34%, the materials of the Level 1 support up to 6.62% and the materials of the Level 2 support up to 37.93%. The proposed local strategy of geometric search can further improve the hybrid algorithm, saving up to 17.88% of Level 2 support materials.

The proposed approach for sliming Level 1 support requires the overhanging region to be a rectilinear polygon and the path direction in a subregion to be vertical or horizontal. This limitation limits the further material savings of the Level 1 support. In future research, the proposed approach can be extended to handle an arbitrary overhang region, each with several choices of path directions.

The details of how to integrate the proposed algorithm into the open-source program CuraEngine 4.13.0 is presented. This is helpful for the designers and manufacturers to practice on their own 3D printers.

The path planning of the overhang is a critical factor influencing the distribution of supporting points and will thus influence the shape of the support structure. Different from existing approaches that use single path directions, the proposed method optimizes the volume of the support structure by planning hybrid paths of the overhangs.

Pressure, being one of the key variables investigated in scientific and engineering research, requires critical and accurate measurement techniques. With the advancements in materials and machining technologies, there is a large leap in the measurement techniques including the development of micro electromechanical systems (MEMS) sensors. These sensors are one to two orders smaller in magnitude than traditional sensors and combine electrical and mechanical components that are fabricated using integrated circuit batch-processing technologies. MEMS are finding enormous applications in many industrial fields ranging from medical to automotive, communication to electronics, chemical to aviation and many more with a potential market of billions of dollars. MEMS pressure sensors are now widely used devices owing to their intrinsic properties of small size, light weight, low cost, ease of batch fabrication and integration with an electronic circuit. This paper aims to identify and analyze the common pressure sensing techniques and discuss their uses and advantages. As per our understanding, usage of MEMS pressure sensors in the aerospace industry is quite limited due to cost constraints and indirect measurement approaches owing to the inability to locate sensors in harsh environments. The purpose of this study is to summarize the published literature for application of MEMS pressure sensors in the said field. Five broad application areas have been investigated including: propulsion/turbomachinery applications, turbulent flow diagnosis, experimentalaerodynamics, micro-flow control and unmanned aerial vehicle (UAV)/micro aerial vehicle (MAV) applications.

The first part of the paper deals with an introduction to MEMS pressure sensors and mathematical relations for its fabrication. The second part covers pressure sensing principles followed by the application of MEMS pressure sensors in five major fields of aerospace industry.

In this paper, various pressure sensing principles in MEMS and applications of MEMS technology in the aerospace industry have been reviewed. Five application fields have been investigated including: Propulsion/Turbomachinery applications, turbulent flow diagnosis, experimental aerodynamics, micro-flow control and UAV/MAV applications. Applications of MEMS sensors in the aerospace industry are quite limited due to requirements of very high accuracy, high reliability and harsh environment survivability. However, the potential for growth of this technology is foreseen due to inherent features of MEMS sensors’ being light weight, low cost, ease of batch fabrication and capability of integration with electric circuits. All these advantages are very relevant to the aerospace industry. This work is an endeavor to present a comprehensive review of such MEMS pressure sensors, which are used in the aerospace industry and have been reported in recent literature.

As per the author’s understanding, usage of MEMS pressure sensors in the aerospace industry is quite limited due to cost constraints and indirect measurement approaches owing to the inability to locate sensors in harsh environments. Present work is a prime effort in summarizing the published literature for application of MEMS pressure sensors in the said field. Five broad application areas have been investigated including: propulsion/turbomachinery applications, turbulent flow diagnosis, experimental aerodynamics, micro-flow control and UAV/MAV applications.

An investigation has been carried out by Quo‐Tec Limited, on behalf of the Department of Trade and Industry's Advanced Sensors Technology Transfer Programme, to determine the opportunities which exist in the UK transportation industries for advanced sensors. The study was concerned particularly with the identification of new business opportunities for UK Small and Medium‐sized Enterprises (SMEs). The study's boundaries were defined as the automotive, aerospace, rail and marine transportation sectors and the advanced sensor technologies of optical fibres and solid state. Piezoelectric, capacitive, inductive magnetoresistive, thin film, thick film and micromachined silicon devices were all included in the term solid state. These were highlighted because of the proven strength of UK research in many of these areas and yet, in many cases, a current lack of significant UK commercial exploitation. Through literature reviews, extensive telephone interviews and face‐to‐face discussions with key individuals in over 90 transportation companies, sensor companies and research institutions, a similar number of sensor requirements were identified. From this number, those requirements best addressed by optical or solid state sensor technology were selected. A criterion applied in the selection was that the need could be addressed by a UK SME (either alone or in collaboration) with a reasonable expectation that a sensor could be commercially available within five years. Preferably, proven technology should be available — the job of a sensor company is to develop the technology into a commercial product, not to do the fundamental research work to prove the technology itself. This article comprises some “prime” opportunities, thus identified, applicable to the automotive industry.

Fabrication of customized products in low volume through conventional manufacturing incurs a high cost, longer processing time and huge material waste. Hence, the concept of additive manufacturing (AM) comes into existence and fused deposition modelling (FDM), is at the forefront of researches related to polymer-based additive manufacturing. The purpose of this paper is to summarize the research works carried on the applications of FDM.

In the present paper, an extensive review has been performed related to major application areas (such as a sensor, shielding, scaffolding, drug delivery devices, microfluidic devices, rapid tooling, four-dimensional printing, automotive and aerospace, prosthetics and orthosis, fashion and architecture) where FDM has been tested. Finally, a roadmap for future research work in the FDM application has been discussed. As an example for future research scope, a case study on the usage of FDM printed ABS-carbon black composite for solvent sensing is demonstrated.

The printability of composite filament through FDM enhanced its application range. Sensors developed using FDM incurs a low cost and produces a result comparable to those conventional techniques. EMI shielding manufactured by FDM is light and non-oxidative. Biodegradable and biocompatible scaffolds of complex shapes are possible to manufacture by FDM. Further, FDM enables the fabrication of on-demand and customized prosthetics and orthosis. Tooling time and cost involved in the manufacturing of low volume customized products are reduced by FDM based rapid tooling technique. Results of the solvent sensing case study indicate that three-dimensional printed conductive polymer composites can sense different solvents. The sensors with a lower thickness (0.6 mm) exhibit better sensitivity.

This paper outlines the capabilities of FDM and provides information to the user about the different applications possible with FDM.

Experts claim over 50% of sensor applications are currently served by silicon‐sensor technology.

To review presentations on assembly and joining given at a seminar, “The changing face of robotics: inside and outside the factory”, organised by the UK Institution of Electrical Engineers.

Details are given of three presentations. The first is by Dr Phil Webb of the University of Nottingham, who described a project to develop a flexible robotic cell capable of riveting and assembling aero‐structure components, in which a new method of “simulation‐based control” evolved. In the second, Pearl Agjakwa of Nottingham University and Craig Johnson of Rolls Royce talked about shape metal deposition, a process by which layers of weld are deposited by robot to form complex aerospace components with minimal tooling and short lead times. The final presentation was by Dr Wolfgang Kölbl of Meta Vision Systems on laser vision robot guidance. Applications in automotive and a new cross vision sensor were described, the latter being applicable to hole location such as for drilling and riveting.

Robotics inside the factory is extending into new areas of assembly and fastening and is now finding applications in the aerospace industry and not just in automotive.

Provides a review of some new assembly‐related process developments in robotics.