Abstract. We report a new investigation into how surface topography and friction affect human touch-feel perception. In contrast with previous work based on micro-scale mapping of surface mechanical and tribological properties, this investigation focuses on the direct measurement of the friction generated when a fingertip is stroked on a test specimen. A special friction apparatus was built for the in-situ testing, based on a linear flexure mechanism with both contact force and frictional force measured simultaneously. Ten specimens, already independently assessed in a 'perception clinic', with materials including natural wood, leather, engineered plastics and metal were tested and the results compared with the perceived rankings. Because surface geometrical features are suspected to play a significant role in perception, a second set of samples, all of one material were prepared and tested in order to minimise the influence of properties such as hardness and thermal conductivity. To minimise subjective effects, all specimens were also tested in a roller-on-block configuration based upon the same friction apparatus, with the roller materials being steel, brass and rubber. This paper reports the detailed design and instrumentation of the friction apparatus, the experimental set up and the friction test results. Attempts have been made to correlate the measured properties and the perceived feelings for both roughness and friction. The results show that the measured roughness and friction coefficient both have a strong correlation with the rough-smooth and grippy-slippery feelings.

2015)Design and control methodology of a 3-DOF flexure-based mechanism for micro/nanopositioning. Copies of full items can be used for personal research or study, educational, or not-forprofit purposes without prior permission or charge. Provided that the authors, title and full bibliographic details are credited, a hyperlink and/or URL is given for the original metadata page and the content is not changed in any way.

In this paper theoretical and experimental studies are carried out to investigate the intrinsic relationship between tool flank wear and operational conditions in metal cutting processes using carbide cutting inserts. A new flank wear rate model, which combines cutting mechanics simulation and an empirical model, is developed to predict tool flank wear land width. A set of tool wear cutting tests using hard metal coated carbide cutting inserts are performed under different operational conditions. The wear of the cutting inset is evaluated and recorded using Zygo New View 5000 microscope. The results of the experimental studies indicate that cutting speed has a more dramatic effect on tool life than feed rate. The wear constants in the proposed wear rate model are determined based on the machining data and simulation results. A good agreements between the predicted and measured tool flank wear land width show that the developed tool wear model can accurately predict tool flank wear to some extent.