Toward an optimal quantitative design method integrating user-centered qualitative attributes.

The determination of product features, which can be seen as design specifications, is a crucial problem that must be carried out upstream to quickly validate the product configuration according to some attributes in relation to the user perception. To this end, the design methods must evolve toward an analysis compatible with various kind of data that can be qualitative or quantitative. In this paper, a new approach is introduced able to take into account various kind of information in order to determine some quantitative design specifications in accordance with the users perception. This is done through a mathematical formulation that exploit different types of data coming from sensory analysis and physical quantities. This mathematical formulation is then used in an optimization procedure that takes into account a preference order over the sensory attributes. The solution of this optimization problem gives thus the best user-centered specifications that must be used for the conception of the final product.

Emotion Measurements Through the Touch of Materials Surfaces.

The emotion generated by the touch of materials is studied via a protocol based on blind assessment of various stimuli. The human emotional reaction felt toward a material is estimated through (i) explicit measurements, using a questionnaire collecting valence and intensity, and (ii) implicit measurements of the activity of the autonomic nervous system, via a pupillometry equipment. A panel of 25 university students (13 women, 12 men), aged from 18 to 27, tested blind twelve materials such as polymers, sandpapers, wood, velvet and fur, randomly ordered. After measuring the initial pupil diameter, taken as a reference, its variation during the tactile exploration was recorded. After each touch, the participants were asked to quantify the emotional value of the material. The results show that the pupil size variation follows the emotional intensity. It is significantly larger during the touch of materials considered as pleasant or unpleasant, than with the touch of neutral materials. Moreover, after a time period of about 0.5 s following the stimulus, the results reveal significant differences between pleasant and unpleasant stimuli, as well as differences according to gender, i.e., higher pupil dilatation of women than men. These results suggest (i) that the autonomic nervous system is initially sensitive to high arousing stimulation, and (ii) that, after a certain period, the pupil size changes according to the cognitive interest induced and the emotional regulation adopted. This research shows the interest of the emotional characterization of materials for product design.

Influence of the shape and material on the behaviour of a total ossicular replacement prosthesis.

OBJECTIVE: To study the influence of the shape and the material on the behaviour of a total ossicular replacement prosthesis (TORP). MATERIAL AND METHODS: It was hypothesized that the influence of the shape and material of a TORP on its performance could be quantified using a simple mechanical model. The prosthesis is represented simply by an axisymmetric shape and two models are used. In the first model, we assume that the strain of the prosthesis is negligible, whereas the strain is taken into account in the second model. In both cases, literature plots of stapes displacement versus frequency are used to check the validity of the modelling. RESULTS: It was found that the influence of the strain of the implant was insignificant in comparison to its rigid body movement. Furthermore, if it is assumed that the reaction force exerted by the inner ear on the stapedial footplate depends on both frequency and mass, it can be shown that the human body is able to adapt itself to the mass and shape of the prosthesis. CONCLUSION: As the prosthesis is not strained and no material criteria appear in the equation used in the modelling, both materials studied, titanium and hydroxyapatite, are equivalent from a mechanical point of view. In addition, a cylindrical prosthesis would give good results in response to an external stimulus but its very rigidity could damage the inner ear during pressure shocks.

A method for accurate localisation of EBSD pattern centres.

The moving screen technique for pattern centre localisation is revisited. A cross-correlation based iterative procedure is developed to find both the zoom factor and the zoom centre (which is also the pattern centre) between two EBSD diffraction patterns acquired at two camera positions. The procedure involves two steps: first, a rough estimate of the pattern centre position and zoom factor (the ratio of the two detector distances) is obtained by cross-correlating the entire images. Then, based on this first estimate, cross-correlation of smaller regions of interest (ROIs) gives the displacement field which is interpreted as a zoom factor misfit coupled with a zoom centre position misfit. These misfits are iteratively decreased until the displacement field is reduced to the noise level. The procedure is first applied to simulated patterns and it is shown that the iterative procedure converges very rapidly to the exact solution with an accuracy better than 1/100th of pixel. The potential of this technique for experimental patterns is discussed and recommendations for new EBSD detectors are proposed.

Comments on the paper "Bragg's law diffraction simulations for electron backscatter diffraction analysis" by Josh Kacher, Colin Landon, Brent L. Adams & David Fullwood.

This comment on the paper "Bragg's Law diffraction simulations for electron backscatter diffraction analysis" by Kacher et al. explains the limitations in determining elastic strains using synthetic EBSD patterns. Of particular importance are those due to the accuracy of determination of the EBSD geometry projection parameters. Additional references and supporting information are provided.