A simulation from a tactile device to render the touch of textile fabrics: a preliminary study on velvet

In the field of e-commerce or virtual prototyping of textile fabrics and garments, tactile stimulators could be very pertinent and useful tools for the industry. The challenge is to stimulate the human hand using a tactile device in order to simulate the textile fabric touch. The principle of the tactile device is described. The kinds of fabrics investigated are pile fabrics, such as velvet. In this study, the illusion of pile is given when touching the smooth plate of the tactile device by modulating the coefficient of friction between the plate and the finger during an active movement. The control signal is qualitatively designed from some tribological features identified in this study as velvet fabric characteristics. The influence of each tribological feature on the tactile rendering is studied via psychophysical studies comparing real and simulated fabrics. The best rendering needs a simulation with three specific features: a coefficient of friction, which depends on the finger movement direction; a transition phase for the change of movement direction; and small amplitude variations of the coefficient of friction with about one millimeter wavelength.