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In order to bridge the increasing gap between the micro‐ and nanotechnologies, a European consortium is currently developing and investigating a cluster of mobile, wireless cubic centimetre‐sized microrobots. The control and sensor issues which are to be solved for such a robot system are demanding. This paper describes the work carried out by one of the project partners. An interferometrical principle employing the so‐called “mechanical” interferometer based on the Moiré‐effect is used for the position sensor system. Further sensor systems involve “local” microscope cameras, for which the extraction of depth information is crucial.

The mismatch of the thermal expansion coefficients of the materials in multiplayer structure may induce serious stress concentrations in electronic packaging. Experimental evaluation of the thermal stresses and strains in those electronic composites is becoming significantly important for optimizing design and failure prediction of the electronic devices.

Digital image correlation (DIC) technique was utilized to obtain thermal deformation filed of a BGA package. With the help of white light to illuminate the cross section of the BGA package, the gray images were taken from the rough surface of the specimen, that offer a kid of carrier pattern for the DIC processing with statistical resemblance in gray distributions. By using the algorithm of correlation computation, the DIC searched the matching spots in a pair of those images in which the spot displacements were involved in between, to obtain the deformation fields of the package specimen caused by temperature changes.

The results show interesting strain distributions in the assembly. Both the horizontal displacement component and its normal derivative are strongly related to the arrangement of the solder joints in the bonding medium between the die and the ceramic substrate. The strain components in the middle region of the package are larger than those in the side regions where the strain relaxation may exist near the stress‐free boundaries. The shear strain components show special bands of parallel lines with identical amount over the chip‐package to sustain the shearing of the packed structure under thermal loading.

The DIC technique shows to be a useful tool for the thermal strain analysis of the electronic packaging devices. Not only provides it the whole field deformation of the assembly, but also maintains the surface pictures of the package without covering any fringes, which is important to compare the deformation field with the specimen surface to reveal the stain distribution related to the failure prediction of the materials.

The paper aims to highlight the importance of having an optical method that can accurately measure the surface finish of 3D printed parts and the influence this has on the total volume of the build.

The paper describes the application of digital moiré to the determination of the surface finish of 3D printed parts.

This study shows that surface roughness plays an important role in the volumetric analysis. There was an increase of 7 per cent from the total volume of the original CAD drawing; in total, there was 19 per cent more material deposited.

This methodology provides a robust tool for future research in the area of geometrical verification and optimization in addition to the potential use for residual stress determination.

This study shows that process optimization can be carried out more efficiently, and it is possible to determine the efficiency of an AM process by directly correlating the processing parameters and accurately comparing the prescribed CAD dimensions/volume to that of the as built part.

By reducing the amount of waste through process optimization, this leads to a reduced consumption of energy which can have a major impact on the environment.

This paper fulfills the need for high accuracy volumetric measurement of 3D printed components.

Discusses the 6th ITCRR, its breadth of textile and clothing research activity, plus the encouragement given to workers in this field and its related areas. States that, within the newer research areas under the microscope of the community involved, technical textiles focuses on new, ‘smart’ garments and the initiatives in this field in both the UK and the international community at large. Covers this subject at length.

Looks at the eighth published year of the ITCRR and the research, from far and near, involved in this. Muses on the fact that, though all the usual processes are to the fore, the downside part of the industry is garment making which is the least developed side. Posits that the manufacture of clothing needs to become more technologically advanced as does retailing. Closes by emphasising support for the community in all its efforts.

A consortium of UK companies has developed a high speed, high accuracy 3D shape acquisition system called Photoform that can dramatically speed up prototype production in a whole range of industries. The system uses a fibre optic laser delivery system to project interference fringes on to a 3D surface, which is then viewed by a camera and analysed to give 12‐micron measurement accuracy over the surface.

This paper discusses some of the general methods by which laser light has been used in engineering measurement. Some objectives set for optical measurement in this field are high repeatability, good resolution and employment of non‐contacting equipment, in the sense of both light source and detector being some tens of millimetres away from the object avoiding obstruction to other processes.

The purpose of this paper is to study the thermal warpage of a plastic ball grid array (PBGA) mounted on a printed circuit board (PCB) during the reflow process.

A thermal-mechanical coupling method that used finite-element method software (ANSYS 13.1) was performed. Meanwhile, a shadow moiré apparatus (TherMoiré PS200) combined with a heating platform was used for the experimental measurement of the warpage of PBGA according to the JEDEC Standard.

The authors found that the temperature profiles taken from the simulated results and experimental measurement are consistent with each other, only with a little and acceptable difference in the maximum temperatures. Furthermore, the maximum warpage measurements during the reflow process are 0.157 mm and 0.149 mm for simulation and experimental measurements, respectively, with a small 5.37 per cent difference. The experimental measurement and simulated results are well correlated. Based on the validated finite element model, two factors, namely, the thickness and dimension of PCB, are explored about their effect on the thermal warpage of PBGA mounted on PCB during the reflow process.

The paper provides a thorough parametrical study of the thermal warpage of PBGA mounted on PCB during the reflow process.

The findings in this paper illustrate methods of warpage study by combination of thermal-mechanical finite element simulation and experimental measurement, which can provide good guidelines of the PCB design in the perspective of thermal warpage during the reflow process.

Fibre optic sensors offer many potential advantages for the measurement of physical parameters in process plants

CURRENT methods for the analysis of stress and mode of vibration of blades, discs and small components are briefly reviewed. Alternative methods using holography are described and compared with conventional methods in terms of yield of information and ease of operation. Finally apparatus is described which will take holograms of objects up to two feet in diameter and may be operated by non‐specialist staff.