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Ever-increasing introduction of new production technologies has significantly reduced manufacturing cycle time in recent years, especially joining technologies. For many industries, Zero Defect Manufacturing (ZDM) is considered as a key strategy to improve Right-First-Time (RFT) capability with a minimum waste of resources. There is a growing desire to move from off-line sample measurement to in-line data collection, which will only be possible with fast, accurate measurement technologies. Although metrology cycle times have improved with in-line measurement systems, their accuracy is not sufficient to meet the tight tolerance demands of typical high value manufacturing applications. A major obstacle to the uptake of new, non-contact measurement technologies is the difficultly in evaluating system capability in terms of repeatability, accuracy and calibration to recognized standards. This study considers these characteristics for a Laser Radar (LR) measurement system applied to an automotive door measurement task. To evaluate these factors, the authors consider: (1) the effect of tooling ball (TB) position and movement on part alignment and measurement feature results and (2) the feature-fitting algorithms applied to different sizes and orientations of hole. The results show that the statically-mounted LR is good at developing a repeatable coordinate system for the workpiece. Offsetting an individual TB had a statistically significantly effect on the repeatability of the measurement results. A number of feature-fitting algorithms were studied, with no algorithm providing a definitively superior result. Two data capture algorithm were considered; hatched and petal algorithm. The petal pattern algorithm is much faster, and was found to provide comparably repeatable results as the hatched pattern algorithm. These results give confidence that the LR system demonstrates good repeatability.

The experiments presented investigate the collapse of a granular column on a stationary surface and a rotating table. A cylinder of radius r0 was positioned on the surface and filled with particulate to a height h0, giving an aspect ratio a = h0/r0. The cylinder was quickly removed and the resultant pile investigated. Spatial and geometric data obtained pre and post collapse were used to derive empirical relations. A high speed camera collected temporal data of the collapse in both cases.\ud \ud In the stationary case a 3D laser scanner quantified measurements of the resultant pile from which scalings involving aspect ratio were derived. The spatial data revealed that the final runout of the pile is not only dependent on the aspect ratio of the initial geometry as previously thought [Lube et al., 2004; Lajeunesse et al., 2004] but also the initial column radius. This was also observed to be true for the angle at the base of the deposit. Theoretical considerations and obtained data allowed the summital angle to be described by material parameters and aspect ratio. X-ray computer tomography allowed observation and quantification of the internal phenomenology to include the granular packing and the failure surface over which the collapse occurs.\ud \ud Consideration was given to the effect of rotation on previously obtained spatial and temporal scalings. Increasing the rotation rate encourages growth in the final pile radius until a critical frequency is reached where material loss begins to occur. Any further increase for fixed a results in further material loss and a decrease in the final pile radius. Initial results from DEM (discrete element method) simulations of granular collapse on a rotating table are presented for the case of spherical particles. In these simulations a spiral pattern evolves where all particles have left the central pile. Laboratory experiments have yet to demonstrate this exact patterning, but comparison to similar investigations suggests its existence.

It is well known that yaw can affect the penetrative power of armour piercing rounds. To\ud investigate this effect purely experimentally is difficult because the typical ballistic set up does not\ud allow control over the yaw angle of the projectile. In this study, a numerical model is used\ud complementing ballistic experiments for a range of yaw angles. For the projectile, a validated\ud computer model of the 30-06 7.62 x 63mm AP M2 round was selected. Surrogate targets were used for\ud a qualitative assessment of the phenomenon. The utilized target is a flat rectangular tile. To encourage\ud yaw in the experimental tests, targets were positioned at relatively close distance to the breach and\ud impact velocity was chosen lower than typical for the projectile. Both ensure that the bullet does not\ud reach stable flight therefore yaw is present. From the experiments, a range of impact velocities and\ud yaw angles was chosen and each of the test conditions simulated. The decrease in bullet velocity ΔV\ud was calculated from high speed video footage captured during tests and compared to bullet ΔV in\ud simulation. Strain condition, predicted damage and negative pressure output from simulation were\ud investigated in pursue of yaw effects on threat level. The results of this study can help in the\ud interpretation of physical test results and ultimately can contribute to making the performance of\ud armour systems more robust.\ud

Small Fe-based droplets have been heated to a molten phase suspended within a slag medium to replicate a partial environment within the Basic Oxygen Furnace (BOF). The confocal scanning laser microscope (CSLM) has been used as a heating platform as it offers the high heating rates necessary for slag and metal to become molten in close time proximity avoiding gradual equilibration during heating. The effect of impurities and their transfer across the metal/slag interface, on the emulsification of the droplet into the slag medium was then examined through X-ray Computer Tomography (XCT) scanning of the quenched sample. This gives the mapping of emulsion dispersion in 3D space, calculating the changing of interfacial area between the two materials, and changes of material volume due to material transfer between metal and slag. Samples were then sectioned and radial chemical analysis is used to identify component surface enrichment or lack thereof. Replication of the previously reported study by Assis et al1 has also been carried out, to show repeatability of the experimental set up and conditions through different users.