The effects of brain-skull boundary conditions on the responses of a simplified three-dimensional finite element model of a thin sagittal slice of the human head were investigated. The model was excited using a time-dependent angular velocity with a magnitude of up to 16 rad/s (maximum angular acceleration, around 5000 rad/s^2). The present study was conducted using the non-linear explicit finite element code LS-DYNA. Three methods for simulation of the brain-skull boundary conditions were investigated : 1) with brain rigidly attached to the skull; 2) using frictionless sliding contact allowing no separation between the brain and skull; and 3) direct simulation of cerebrospinal fluid (CSF) using a layer of eight-noded solid elements with fluid-like properties. Varying the method for simulation of the brain-skull boundary conditions appreciably affected the brain responses. However, varying parameters of a given method, such as viscosity of CSF and CSF-skull friction coefficient, exerted only minor effects on these responses. The present results suggest that accurate simulation of brain-skull boundary conditions requires direct representation of the subarachnoidal space/CSF as a fluid-like medium.

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As elderly society progresses, development of machines for assisting human to walk is getting more important nowadays. We develop two cart-type machines to assist walking and evaluate the effect of this machine on the muscle tension and energy consumption of the user. Our evaluation method will be useful for developing a walker for practical purposes.

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High performance and multi-functional sensor/actuator materials is essential key technology developing smart/intelligent devices and systems. Fine fiber and foil-type sensor/actuator material elements of thermoslastic, ferromagnetic and magnetoelastic alloys were developed by using the originally designet rapid solidification (RS) melt-spinning apparatus. Those RS had strong crystalline texture with fine columnar grains that were uniquely formed during rapid-solidification process. These sensor/actuator material elements become useful to develop the high performance micro-electronic mechanical systems and intelligent/smart composite materials and structures. Several potential designs for faster composite actuator, medical catheter gripper and smart composites board for structural health-monitoring are shown as preliminary application proposals based on this study.

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Research at the Sussex Nanoscience & Nanotechnology Centre (SNNC) has produced a number of novel nanostructures from different starting materials under varying conditions. Some excellent work in nanoscale architecture has resulted in the formation of SiO_x nanowires and ceramic nanofibres of MgO (wishbone/fern structures).

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