Maeno Takashi

This research proposes a quantification method for tactile evaluation by hierarchically classify tactile sensations into three groups named low-order of tactile sensation (LTS), high-order of tactile sensation (HTS) and desired tactile sensation (DTS). A sensory evaluation was conducted and factor analysis was performed to extract the common potential factors in each group. Next, multiple regression analysis was used to determine and examine the relationship between LTS-HTS, and HTS-DTS. Then, multiple physical quantities for quantification were measured. After that, the LTS factors were quantified by using the measured physical quantities. As a result, DTS adjectives were also quantified. Lastly, a verification test was conducted and the result showed that the proposed method may possibly evaluate unknown samples' tactile sensation from measured physical quantities.

It has been found that human recognize tactile sensations by feeling the following four factors (friction, smoothness, hardness, thermal). A tactile display that can represent the four factors mentioned earlier was developed. This tactile display makes use of haptic devices an ultrasonic vibrator and a thermal display. The haptic devices reproduce the feeling of friction. The ultrasonic vibrator reproduces the feeling of smoothness and hardness by modulating the amplitude of the wave flowing through the material. The thermal display which consist of a Peltier element, reproduces the thermal feeling of materials. The tactile display presented and simulated to users different types of cloth materials; test subjects were able to discriminate the difference and properly tell which tactile display was simulating which cloth.