Human tactile perception as a standard for artificial tactile sensing - a review

Abstract

In this paper, we examine the most important features of human skin tactile properties with special emphasis on the characteristics which are vital in the design of artificial systems. Contrary to the visual and auditory senses, the touch signal is not a well-defined quantity. As a result, the researchers of this field are still dealing with the basics of collecting the most relevant data. Following this, mimicking the sense of touch by producing artificial tactile skin is a challenging process. Although the sense of touch is widely distributed all over the human body, the tactile perception in the human hand is of great importance in terms of surgical and medical robotics applications. In this study, the role of various mechanoreceptors in the human hand, such as, RA, SA I, SA II, and PC units are discussed in relation to the stimuli like force, position, softness, and surface texture. Taking human hand as a suitable tactile model, the necessary engineering features of an artificial tactile sensor, such as, spatial and temporal resolutions, force sensitivity, and linearity, are being reviewed. In this work, we also report on the current and possible future applications of tactile sensors in various surgical procedures.

A narrative review on haptic devices: relating the physiology and psychophysical properties of the hand to devices for rehabilitation in central nervous system disorders

“…Activation of the FA-I afferent receptors is associated with the perceptual sensation of a flutter, rather than the deep and diffuse feeling that tends to follow FA-II activation [67]. FA-II afferents are extremely sensitive to high frequency stimulation due to the structure of the afferent ending and the layers of connective tissue surrounding them.…”

“…FA-II afferents are extremely sensitive to high frequency stimulation due to the structure of the afferent ending and the layers of connective tissue surrounding them. This ensures that only high frequency stimulation reaches the afferent nerve [67]. FA-II afferent units, responsible for sensing vibrotactile feedback, have a large receptive field that may encompass whole regions of the fingertip [8] and account for 40% of the glaborous skin mechanoreceptors [68].…”

“…In this way, simulation of a flat surface or object can be achieved by utilising contact points separated by distances which are below the two point discrimination threshold. Darghai et al [67] demonstrated that application of a 10x15 1mm actuator array may be used to convey a perception of a smooth object surface. It is worth noting that when two stimuli are presented successively, rather than simultaneously, the inter-point discrimination distance is considerably smaller which is attributed to the role of the Meisner corpuscles in active touch [67].…”

“…Darghai et al [67] demonstrated that application of a 10x15 1mm actuator array may be used to convey a perception of a smooth object surface. It is worth noting that when two stimuli are presented successively, rather than simultaneously, the inter-point discrimination distance is considerably smaller which is attributed to the role of the Meisner corpuscles in active touch [67]. As a result, the design of haptic devices is dependent on the nature of the task being simulated.…”

Experimental and Theoretical Analysis of a Novel Flexible Membrane Tactile Sensor

“…Normally, in order to improve the efficiency of these types of sensors, an array of sensors is utilized [6,7] . Force and position signatures are the two factors that can provide a great deal of information about the state of gripping or manipulation of a biological tissue [8] .…”