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Hydrophilic/hydrophobic behavior on Ti foil surface prepared during anodization process was examined. The titanium foils were anodized in electrolyte contained 0.25wt% NH4F, 2.5vol% water and the ethylene glycol under direct voltage of 40V at room temperature for 3h. The anodized specimens were oscillated in ultrasonic clearer for 10 min or 30 min. The surface morphologies of the specimens during different stages of the process were observed by field-emission scanning electron microscopy (FESEM). The wettability of specimen surface was estimated by measuring contact angle (CA) of water droplets on specimen surface. The results show wetting angle on the surface of the Ti specimens after anodization process is at the range of 149° to 153°, indicating hydrophobic or even superhydrophobic property. CAs on the anodized specimens after oscillation in ultrasonic clearer is at the range of 25° to 42°, indicating the hydrophilic property. Hydrophilic/hydrophobic behavior on Ti foil surface during the process was explained by morphology on titanium surface.

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In order to help elder people who suffer from lower back pain caused by lower spine degeneration, a novel kind of robot-assisted exoskeleton spine was designed. It was mainly applied to lift their upper bodies for assisting movements and reducing backache during walking. The aim of this system was to control an elastically actuated motor to provide extra torques on a user's hip by following the gaits in locomotion. And the whole exoskeletal spine mechanism (exo-spine) has been built of flexible material and fixed on an artificial pelvis. Thanks to the use of a cablepulley-spring structure the torque applied to the hip is greatly amplified and would eventually affect the deformation of exo-spine, so that an auxiliary force is generated on the lower back to support user's spine during the movements. Although the overall robot-assisted system was easily imaged and designed, its intrinsic complexity needed careful analysis, because the actuating process becomes highly nonlinear and noisy when compliant movements are demanded to mimic human performances in locomotion. Therefore, some appropriate assumptions were introduced, and to enhance the robustness of system, an adaptive controller was designed by applying Lyapunov Stability Theory. Finally, the correctness and feasibility of our proposed system were tested and estimated through a set of experimental simulations.