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We focus on research to develop a compact human blood sampling device used for the Self Monitoring of Blood Glucose (SMBG). The SMBG comprises: (1) an indentation system using a shape memory alloy (SMA) actuator to force a microneedle through the skin; (2) a micro electrical pumping system to extract blood using a bimorph type piezoelectric microactuator; (3) a biosensor using an enzyme such as glucose oxidase (GOx) to detect and evaluate the amount of glucose in extracted blood. A titanium microneedle the same size as a female mosquito's labium (60 mum outer diameter, 25 mum inner diameter) was produced by the sputter deposition method. The mechanical design of the device was based upon the mosquito's blood sampling mechanism. The blood extraction system worked well. We measured the performance of the principal components: the indentation load for a microneedle of external diameter 100 mum was found to be 0.1 N. The pumping system has an extraction speed of about 2 mul/min for whole blood. This is similar to that achieved by the mosquito.

For the simulation of mechanical behaviours of textile composite materials and structures, a novel hierarchical modelling technique is proposed. Not only the global deformation but also the stresses at multiscales are analysed precisely. Four-level hierarchy is defined for the textile composites such as woven and knitted fabric composites. The stresses at the mesostructure, which is a periodic unit cell of textile composite materials consisting of fibre bundles and matrix, can be evaluated accurately by the homogenization method and finite-element mesh superposition technique. The latter technique makes it possible to overlay arbitrary local fine mesh on the global rough mesh. Anisotropic damage mechanics is also utilized for strength evaluation at the mesoscale. Three-dimensional modelling of the mesostructure of woven and knitted fabric composite materials is shown. Localization analysis has been carried out within practical computational time and cost by the proposed hierarchical modelling.

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Polycrystalline piezoelectric materials are aggregations of crystal grains and domains with uneven forms and orientations. Therefore, the macroscopic ferroelectric property should be characterized by introducing a microscopic inhomogeneity in the crystal morphology. In this study, a multi-scale finite element modelling procedure based on a crystallographic homogenization method has been proposed for describing a macroscopic property of polycrystalline ferroelectrics with consideration of the crystal morphology at a microscopic scale. The proposed procedure has been applied to two kinds of piezoelectric materials, BaTiO3 and PbTiO3 polycrystals; the influence of microscopic crystal orientations on macroscopic ferroelectric properties was verified numerically. From the computational results, it has been shown that piezoelectric constants of polycrystalline ferroelectrics can be maximized by design of microscopic crystal morphology.