When a human touches an object surface by using its fingers, friction is a major cue for judging a variety of surface features including microscopic surface roughness, softness, and wetness. Human perceives the friction through the deformation of their finger pads caused by friction forces. Such forces can be quasi-static and dynamic and they influence the perceived worth of products. This paper explains how friction determines the textural perception including affective values, and provide a design guideline of human- and skin-friendly materials and products.

The human fingertip can instantly grasp the sense of touch when it touches a material, but this tactile perception is based on the processing of very complex information. If the delicate sensation of the fingertip can be quantified by tactile sensor technology, it is expected that tactile technology will be developed in new application fields by combining it with advanced information processing technology such as deep learning. This paper describes the development status of high-performance tactile sensors that quantify and visualize the delicate sensation at the fingertips, and discusses human tactile perception and sensation with a tribological perspective.

A biomimetic tactile sensing system focusing on the friction phenomenon occurring on the skin surface was developed. In this system, a finger model contact probe that mimics the shape, surface and mechanical properties of a human finger was attached. Furthermore, the probe slid in a sinusoidal motion to imitate the smooth motion when a human touches an object. In this paper, we present the evaluation of human skin, cosmetics, foods, and paints using the sensing system.

In this paper, we provide a survey of tactile display technologies, which is one of important parts for IoT-like networks 'informotion'. Since tactile displays generate tactile sensation by means of contact between human skin and display surface, we expect that tribology will provide important fundings to produce the tactile displays. Furthermore, tactile science makes tribology realm be progressed because of psychological and physiological information processing caused by contact between human skin and display surface. After we survey the tactile displays produced for the last 10 years, we summarize effective technologies for development and utilization of the tactile displays such as tactile data acquisition system, smoothness presentation using velvet hand illusion and arm movement presentation using kinesthetic illusion.

Haptic sensation depends on our individual bodies as well as objects since it is derived from mechanical interaction between our bodies and objects. Skin characteristics and sensorimotor control are relevant to haptic sensation. Thus, haptic sensation involves our physical skills. In this paper, informalization and applications of individual haptic sensations are discussed. As a method to detect individual tactile sensations, a wearable skin vibration sensor is introduced, and its applications are shown. Tactile feedback can augment the perception and can be available to improve the sensorimotor control. Sharing of tactile sensations improves human-robot collaboration. Furthermore, body integration using an avatar robot, in which multiple operators cooperate the single robot, is introduced with its effect on the operability and sense of agency.

This article explains the technology required to present tactile cues for dexterous manipulation using hand fingers in virtual reality. Regarding sliding and rolling occurring in finger manipulation, the characteristics of the mechanoreceptors of fingers, and the adjustment of grip force, it seems necessary to present contact force, including friction, corresponding to the manipulation to reproduce dexterous manipulation in virtual reality. It starts with the flow of reproduction (= haptic interaction), explains the computation method for the simulation, and mentions the trade-off between presentation accuracy and interference with the manipulation of a device that presents contact force (= haptic interface).