Skip to content Skip to sidebar Skip to footer
Home / Skin Receptors Communicating the Sensation of Heavy and Continuous Touch and Pressure Are Known as

Skin Receptors Communicating the Sensation of Heavy and Continuous Touch and Pressure Are Known as

Post a Comment

Mechatronic Support Systems and Robots

Armin Schneider , Hubertus Feussner , in Biomedical Engineering in Gastrointestinal Surgery, 2017

10.3.1 Haptic Feedback

Tactile perception is a part of a complex human sensory system consisting of

1.

proprioception (body awareness),

2.

mechanoreception (touch),

3.

thermoreception (temperature),

4.

nociception (pain).

In surgery it is of utmost importance to feel a quality of the tissue and the anatomy:

•

to identify the surgical planes,

•

to locate a tumor,

•

to grip tissue firmly but atraumatically,

•

to cut and to spread with adequate force,

•

to apply the adequate tension when a knot is tied.

In open (conventional/classical) surgery, palpation is an essential part of surgical exploration. It is crucial for palpation of the tissue to discriminate the different layers and anatomical structures. It is the precondition to cut and to spread tissue with adequate force, to find the best trade-off when grasping between a secure grip and trauma or to apply optimal tension when a knot is tied.

In laparoscopic surgery tactile feedback is hampered but not at all completely eliminated. However, in robotic master–slave systems a direct (mechanical) control of the tip of the instrument via the respective handling device is no longer possible. Accordingly, the creation of artificial haptic feedback would be utmost desirable.

At first glance, however, to create robotic haptic feedback seems to be nearly unsurmountable.

Touch or tactile perception is one of the five somatosensory senses encompassing our capability to perceive pressure, stretch, and vibration (Fig. 10.52).

Figure 10.52. With the exception of (bimanual) palpation, tactile feedback is mediated by the respective instrument.

 All from MITI.

The loss of tactile perception is mostly compensated by visual control (otherwise, a DaVinci system would be of no use in clinical care), but, nevertheless, the use of the full range of surgical skills is limited. Accordingly, it would be most desirable to find technical solutions to provide the user with tactile information via the interface. The task is challenging.

The problem may become a bit less complicated if it is considered that haptic feedback in surgery is mainly mediated by the hand instruments in use. Direct manual palpation is of minor importance. Since a tool—a technical system—is per se better suitable to measure forces, the task should become easier to solve.

The main resistive forces which have to be transmitted to the interface are

•

orthogonal force to the yaws,

•

axial resistive force,

•

lateral forces.

Orthogonal force is exerted to the yaws of the instrument when the tip is opened or closed, e.g., to grasp the tissue, or to secure a needle in a stable position, or to cut (Fig. 10.53A).

Figure 10.53. (A) Optimal fixation without harm to the object; (B) particular fine touch is required to spread apart different planes.

 All from MITI.

The opening force plays a role if different plans have to be spread apart (Fig. 10.53B).

If the instrument is moved forward or backward, the amount of resistive force when pushing or pulling is also decisive (Fig. 10.54).

Figure 10.54. (A) Elevation of the liver; (B) pulling adhesions from the gallbladder: the adequate amount of traction is decisive.

 All from MITI.

Last but not least, lateral force has to be transmitted as well (Fig. 10.55A).

Figure 10.55. Haptic feedback is more than the perception of orthogonal forces! (A) Orthogonal force when piercing the tissue with the needle; (B) traction–countertraction if a knot is tied.

 All from MITI.

The next level is to reflect the forces if the two actors are working together (Fig. 10.55B).

In at least two systems, haptic feedback was already successfully implemented: the Senhance Surgical Robot System and the MiroSurge device reflect forces. The clinical effectiveness has still to be evaluated.

Read full chapter

URL:

https://www.sciencedirect.com/science/article/pii/B9780128032305000105

Haptic interfaces

Peter P. Pott , in Endorobotics, 2022

11.1.1 Introduction

Haptic describes the sensory and motor skills in the skin, joints, muscles, tendons, and ligaments.

Tactile describes the mechanical interaction with the skin. Tactile perception is the perception of exclusively mechanical interaction: normal and shear forces, moments, (angular) acceleration, (angular) speed, and heat.

Kinesthetic refers to both actuator and sensory properties of muscles and joints canthus considering forces and moments, positions and angles, and movements. As a result, every external kinesthetic interaction has a tactile component.

A haptic device (Fig. 11.1) is a system that provides mechanical output, which can be perceived haptically. It thus has at least one output, but not necessarily an input. The markings on the letters F and J of a keyboard are tactile patterns that transport information on the (right) position of the index finger. These simple keys are already tactile devices determined by their surface. Going further into detail of the key, it becomes clear that the characteristic curve of the spring holding the key in place has a second feature. It is producing the force felt by the user when he or she presses the key. This is designed in a way that a clear sensation of the fact that the key has been pressed is available. This information is propagated kinesthetically by the skin, muscles, and joints of the user. Thus, these simple keys are already a haptic device.

Fig. 11.1

Fig. 11.1. System structure of a haptic display and input device in a telerobotics setup.

Read full chapter

URL:

https://www.sciencedirect.com/science/article/pii/B9780128217504000116

Bioinspired interfacial drag-increase structure enhancing force perception

Deyuan Zhang , ... Xiangyu Zhang , in Micro- and Nano-Bionic Surfaces, 2022

8.3.1 Drag-increase structures in tree frog toe/human finger

In nature, creatures have evolved excellent tactile organs to perceive their environments. For instance, in human fingertips, the tactile perception is also mediated by skin vibrations generated as the finger scans the surface ( Fig. 8.12A and B ). When the sensor surface is patterned with parallel ridges inspired by the fingerprints, the spectrum of vibrations elicited by randomly textured substrates is dominated by one frequency set by the ratio of the scanning speed to the inter-ridge distance [12]. In addition, the tree frog toes with complicated surface textures can not only increase the grasping force in wet interface [13] but also can detect slipping with the mechanoreceptors beneath the surface textures (Fig. 8.12C and D). These structure-enhanced sensing mechanisms in nature probably benefit the development of the tactile and slip sensors.

Fig. 8.12

Fig. 8.12. Mechanoreceptors and surface structures of a human fingertip and a tree frog toe. (A) The structural and functional characteristics of human fingertips. Fingertip skin consists of slow-adapting mechanoreceptors [Merkel (MD) and Ruffini corpuscles (RE)] for static touch and fast-adapting mechanoreceptors [Meissner (MC) and Pacinian corpuscles (PC)] for dynamic touch. (B) Optical image of human fingerprints; (C) mechanoreceptors under the dermis of tree frog toes observed by fluorescence staining; (D) SEM images of the surface textures on the tree frog toes.

 Reproduced from Y. Jiang, Z. Ma, B. Cao, L. Gong, L. Feng, D. Zhang, Development of a tactile and slip sensor with a biomimetic structure-enhanced sensing mechanism, J. Bionic Eng. 16 (2018) 47–55, with permission of Springer Nature.

Read full chapter

URL:

https://www.sciencedirect.com/science/article/pii/B9780128245026000065

Garment fit and comfort

Apurba Das , R. Alagirusamy , in Science in Clothing Comfort, 2010

8.3.3 Evaluation of tactile perception to fit

Various methods have been developed to measure the human perceptions, like odours, tastes etc. Ashdown and DeLong [7 ] adapted the test method for measuring tactile perception to fit, which was developed by the ASTM Committee E-18 for sensory evaluation of products. Constant stimulus difference (i.e. difference from control value) test was used as the model in the development of the perception of fit tests. Two types of thresholds were identified by this test: the difference threshold (or) the extent of change in the stimulus that produces a noticeable difference; and the recognition threshold (or) the extent of change in a stimulus necessary for positive identification of the difference. In the first part of this test a series of garments (pants) along with their corresponding control (garments) were presented to a panel of experts. The experts then rated the difference of the sample from the control. The scale for pants provided the response choices of 'looser', 'a little looser', 'the same', 'a little tighter' and 'tighter' for the waist, hips and crotch. The second part of the perception test was designed to address the large number of interactions that occurred in the first part of the perception test. In order to focus the subjects' attention on one area of concern, they were told what area of the test samples (pants) would vary from the control sample. The second test was therefore performed with variations at a single location. Two experts were asked to respond to test samples (pants) with hip or crotch variations. In the second type of perception test, the experts were informed that the variations were all at this specific location. The final perception test was carried out to determine the significance of the thresholds perceived in relation to comfort or discomfort perceptions with garment fit. The participants were given only the test garment that they had perceived as different from the control to try on in a preference test. A mirror was provided and subjects were asked to indicate whether they found the garments are comfortable or not, even though they perceived differences from the control garment.

Psychophysical scaling technique was used by You et al. [14] to assess the pressure perception and other relative wearing sensations during wearer trials of tight-fitting garments. The sense of pressure was recorded on a scale of 0–10. One tight-fitting pant, with very high clothing pressure, as presented to subjects as the standard for the maximum degree of pressure, was indexed as 10. On the other hand, when the subject was naked, i.e. at the minimum degree of pressure, the scale was indexed as 0. The subjects were asked to rate the sense on a scale 0–10. Every subject was asked to assess the pressure sensation of each area while wearing the garments.

Read full chapter

URL:

https://www.sciencedirect.com/science/article/pii/B9781845697891500080

Crew errors in the safety assessment

Duane Kritzinger , in Aircraft System Safety, 2017

10.2.2.1 Step 1a: design for physical attributes

These early ergonomic evaluations are meant to ensure that the design team adequately considers basic physical characteristics and control interfaces. Areas to concentrate on include positioning, reach, field of view, knob/button size, tactile perception, labelling, system usability, etc. Aircraft controls supplement aircraft displays in communicating to the pilot ( Jarrett, 2005). It provides a two-way interaction between the aircraft and the crew. Controls should be easy to reach and be positioned appropriately in accordance to their usage. Controls which are used frequently should be positioned in a more prominent position. Controls should move in the natural sense and controls that complement each other or frequently used in conjunction of each other should be grouped together if possible.

Read full chapter

URL:

https://www.sciencedirect.com/science/article/pii/B9780081008898000106

Mechanical tactile properties

J.Y. Hu , ... K.W. Yeung , in Clothing Biosensory Engineering, 2006

16.1 Introduction

The concept of fabric hand has long been used in the textile and clothing industries as a description of fabric quality and prospective performance. 23 During wear, clothing contacts and interacts with the skin of most parts of the body dynamically and continuously. The properties of the fabric hand, which describe the feeling during the contact between human skin and fabric, have been extensively studied through objective measurement and subjective sensory descriptors. Normally, fabric handle can be perceived subjectively by hand. When fabric is manipulated with the fingers, many psychological sensations such as stiffness or rigidity, softness or hardness, warm or cool, wet or dry are perceived. 5 A considerable volume of research outcomes has been reported on various tactile and pressure sensations including prickliness, itchiness, stiffness, softness, smoothness, roughness, scratchiness and fitness. 2 , 3 , 6 , 11 , 15 , 18 These fabric proprieties not only affect comfort sensations but also influence their aesthetic qualities, which may motivate consumers to make purchase decisions.

Traditionally, fabric handle is judged by experts, and many problems arise due to disagreement. 19 , 22 Quantification of tactile comfort is complex because of the range of responses that people experience when they touch and move a fabric with their hand or on their skin. However, since this property is very influential in a consumer's decision-making process, much work has been done to quantify the factors that comprise fabric handle.

Neurophysiological research found that the various sensations resulting from the skin-fabric interaction are triggered by sensory receptors. There are three categories of receptors, which cover pain, thermal and touch sensations. During fabric-skin contact, the fabric produces pressure and vibration on the skin and stimulates the touch receptors. Mechanoreceptive nerve fibers related to tactile perception have the following characteristics: 8

•

each receptor has a different frequency tuning;

•

light stimulation at a particular frequency will cause only receptors tuned to that frequency to respond;

•

intense stimulation at a particular frequency will cause all receptors to respond;

•

relative stimulation across all types of receptors (across-fiber-pattern coding) underlies our perception.

Peirce 18 was the first to describe the relationship between measuring fabric properties and handle. He proposed that the sensations of stiffness, hardness and roughness were based on the fabric properties, e.g. bending, flexural rigidity, thickness and compressibility. Peirce concluded that fabric stiffness was the key factor in the study of fabric handle. Lindberg et al. 14 later established the relationship of properties and garment appearance of fabric by measuring fabric shear, tensile, bending and formability properties. They also developed the test procedures and experimental equipment to measure these properties.

Hu et al. 7 used a stepwise regression method to obtain the best-fit Stevens' law equations containing the minimum number of independent variables (KES-F parameters) to predict fabric stiffness, smoothness, softness and fullness.

Pan and his co-workers 17 developed a more logical and rational mathematical process called 'Euclidean distance' calculation. This method has been proved to be more suitable for different textile and fabric markets. Another approach developed by Raheel 21 used a fuzzy comprehensive evaluation to predict hand. The model is very useful for quality judgement, but it has not proved reliable in different markets.

Due to work performed by Kawabata, 9−11 and a number of other researchers, 2 , 12 , 16 , 20 a knowledge base of objective fabric sensory values now exists. Kawabata was the first researcher to separate handle into three levels: mechanical properties, primary handle values and total handle value. He developed several apparatus to evaluate fabric handle properties. The original KES-F developed in 1972 consists of four components, which allow the measurement of properties of planes (fabrics, knitted fabrics or films). There is also a newer apparatus-combination for the evaluation of thermal properties.

The FAST system, developed by CSIRO in Australia, is another set of instruments and test methods, which can assess fabric properties by measuring thickness at two predetermined loads, bending, extensibility of the fabric in the warp, weft and bias directions as well as relaxation shrinkage and expansion on individual instruments. 4

Some standards and test methods relevant to fabric mechanical tactile comfort are summarized in Table 16.1. ASTM standard D123 on terminology gives the following as important terms for describing fabric handle: 1

Table 16.1. Several fabric mechanical tactile comfort measurement relative standards

Developer Document number Title
AATCC Evaluation procedure 5 Fabric Hand: Guidelines for the Subjective Evaluation of
ASTM D1388 Standard Test Method for Stiffness of Fabrics
D4032 Standard Test Method for Stiffness of Fabric by the Circular Bend Procedure
D2261 Standard Test Method for Tearing Strength of Fabrics by the Tongue (Single Rip) Procedure (Constant-Rate-of-Extension Tensile Testing Machine)
D4255/D4255M Standard Test Method for In-Plane Shear Properties of Polymer Matrix Composite Materials by the Rail Shear Method
D6571 Standard Test Method for Determination of Compression Resistance and Recovery Properties of Highloft Non-woven Fabric Using Static Force Loading
D3822 Standard Test Method for Tensile Properties of Single Textile Fibers
•

flexibility – ease of bending;

•

compressibility – ease of squeezing;

•

extensibility – ease of stretch;

•

resilience – ability to recover from deformation;

•

density – mass/unit volume (refers to light or heavy perception);

•

surface contour – divergence of the surface from the fabric plane;

•

surface friction – resistance to slipping;

•

thermal character – apparent difference in temperature of the fabric and skin.

ASTM D4255/D4255M described a method to determine the in-plane shear properties of high-modulus fiber-reinforced composite materials using either one of two procedures. In Procedure A, laminates clamped between two pairs of loading rails are tested. In Procedure B, laminates clamped on opposite edges with a tensile or compressive load applied to a third pair of rails in the centre are tested. The limitation of the method is that it is only suitable for continuous-fiber or discontinuous-fiber-reinforced polymer matrix composites. ASTM D6571 described a method to measure the compression resistance and recovery properties of any type of highloft non-woven fabric using a simplistic and economical applied static weight loading technique. ASTM D3822 covers the measurement of tensile properties of natural and man-made single-textile fibers of sufficient length to permit mounting test specimens in a tensile testing machine. ASTM D1388 covers the measurement of stiffness properties of fabrics by measuring the bending length and calculating the flexural rigidity. ASTM D4032 determines the stiffness of fabrics by using the circular bend procedure. ASTM D2261 can be used to determine the tearing strength of textile fabrics by the tongue (single rip) procedure using a recording constant-rate-of-extension-type (CRE) tensile testing machine.

Although there are methods and instruments that can be used to measure fabric tactile properties, most of them only can be employed to determine fabric tactile properties on a series of separate apparatus. To meet the need for a new model of integrated intelligent fabric tactile tester, which can measure, record and analyze the thermal and mechanical properties in one step, a new instrument named a Fabric Smart Tactile Tester (FSTT) has been developed, which is able to measure the fundamental mechanical and thermal sensory signals at the same time and under the same climatic conditions. 13

Read full chapter

URL:

https://www.sciencedirect.com/science/article/pii/B9781855739253500162

Sensing Materials

Hendrik N.J. Schifferstein , Lisa Wastiels , in Materials Experience, 2014

Comparing the contributions of vision and touch

All the different senses are used simultaneously and thus may influence the overall perception of warmth. However, it remains to be established empirically to what extent each sensory modality contributes to the overall experience. Experimental studies have shown that the contributions of the sensory modalities to experience aspects tend to be product dependent (Fenko et al., 2009b).

Fenko et al. (2010b) investigated the relative importance of color vision and tactile perception for the product experience of warmth. In a prestudy, participants rated the warmth of various colors and materials and, subsequently, the authors picked one warm and one cool stimulus for each sensory modality. For the main study, the authors created different types of products (scarves and breakfast tables) by combining these warm and cold stimuli (colors and materials) in all four possible combinations and asked respondents to evaluate the warmth of each product. The results demonstrated that for both these products color and material contributed equally to the judgments of warmth.

In a similar study investigating the contribution of material and color to the perceived warmth of wall elements, however, Wastiels et al. (2012a) found that vision clearly dominated the experience. Responses for a visual condition were similar to those in a multisensory (vision   +   touch) condition, whereas the results in the touch-only condition highly deviated. Apparently, when wall materials are perceived visually, touching the material does not alter the perception of material warmth. Additional studies on sample sets varying in color and roughness (Wastiels et al., 2012b) revealed that the effects of color on the perception of warmth were considerably larger than the effects of roughness. These outcomes support the idea that vision has a very large impact on the general assessment of material warmth within an architectural context.

Read full chapter

URL:

https://www.sciencedirect.com/science/article/pii/B9780080993591000023

Knitted Electronic Textiles: From the Design to the Integration Process

Rita Paradiso , Laura Caldani , in Wearable Sensors (Second Edition), 2021

• Water handling according to the finishing process

There are a series of finishing techniques currently available on the market for the use of moisture management in textiles. The main ones are correlated to the hydrophilic or hydrophobic proprieties of the water-exposed surface. The use of finishing processes can affect washing fastness and the tactile perception of the material. Moreover, such treatments are not very environmentally friendly or permanent. The extra process of finishing may also affect the conductive properties of the yarns at the surface level. Most of the sensors to be used for the detection of vital signs and user movements need to be in close contact with the skin or need to closely follow the body's contours. For this reason, most of the wearable solutions have to be as close as possible to underwear and to the second skin concept. Seamless knitting on a Santoni seamless machine would provide elastic, adherent, comfortable garments with these inherent properties. Seamless technology allows knitting differentiated structures in the same fabric. As an alternative to the Santoni machine, a flat-knitting machine will handle different yarns on mono or double fabric structures, depending on the specific functional design.

Read full chapter

URL:

https://www.sciencedirect.com/science/article/pii/B9780128192467000085

Human Nervous System and Behavioral Toxicology☆

N. Fiedler , in Reference Module in Biomedical Sciences, 2014

Sensory Function

The ATSDR recognized the need to evaluate sensory as well as cognitive function in the battery recommended for use in environmental health field studies (Hutchinson et al., 1992). Tests of visual, auditory, and tactile sensory function were included in a battery to evaluate individuals in communities potentially exposed to hazardous waste sites. Tests of audition range from simple evaluation of hearing with an audiometer to more complex tests assessing the ability to discern speech or rhythmic patterns (e.g., SCAN-A, competing words test (Keith, 1994 )). Tests of tactile perception and vibration sense include simple tactile perception (finger agnosia) and sense of vibration using a device to measure perception of fine vibrations in the finger or toe ( Anonymous, 1991; Heaton et al., 1991). These tests have successfully detected losses of peripheral sensory perception due to mercury or solvents.

Of interest is the finding of color vision loss among solvent-exposed workers (Braun et al., 1989; Mergler and Blain, 1987). Benignus et al. (2005) completed a meta-analysis of studies evaluating color confusion index in response to long-term styrene exposure and observed color vision deficiencies benchmarked against the loss that occurs with aging (i.e., 8 work years at the rate of 20   ppm results in 1.7 added years of age). Visual contrast sensitivity reflects the threshold where a person can recognize a sine wave pattern against a background of decreasing contrast. This test was used in a number of occupational and environmental studies evaluating the effects of chronic exposure to neurotoxicants (Waksman and Brody, 2007). Some studies report reduced contrast sensitivity among workers chronically exposed to organic solvents (Frenette et al., 1991). Finally, altered sense of smell may occur with exposure to neurotoxicants. Schwartz et al. (1990) reported dose-related decrements in olfactory function as measured with a test of olfactory discrimination (University of Pennsylvania Smell Identification Test (UPSIT)) (Doty, 1995). These deficits were observed among workers exposed chronically to low levels of organic solvents, suggesting that such sensory tests may be sensitive indicators of the effects of long-term, low-level exposure. In addition to the direct effect of neurotoxicants on olfactory function, malodors from exposure could mediate the effect of neurotoxicants on neurobehavioral performance, particularly for those tasks of executive function such as attentional control and inhibition, subserved by the same regions of the orbitofrontal cortex (Rohlman et al., 2008).

Read full chapter

URL:

https://www.sciencedirect.com/science/article/pii/B9780128012383022078

Tactile Aesthetics of Materials and Design

Hengfeng Zuo , ... Mark Jones , in Materials Experience, 2014

Fundamentals of the sense of touch

Most fundamental research of touch has been conducted in the field of psychology, and the main focus of interest is to discover the perception mechanism, e.g., role of vibration in perception of roughness, with both the external factors (object) and internal factors (skin, finger moving rate, applied fingertip force, etc.) taken into consideration. The main target of this kind of research is to understand human ability and manipulation of touch behavior in daily life. The documented pioneer study on touch can be dated to approximately the 1920s, conducted by Katz (1925, 1930, 1989).

Understanding the fundamental phenomenon and features of the touch process will help in observing and analyzing tactile interaction with materials, and will be useful in guiding experimental research design and explaining some of the experimental results. Touch is usually classified as somatosensation, which generally refers to sensations of the body. In the initial stages of tactile perception, sensory processing begins in receptors. A given receptor cell will detect particular energies or chemicals. Typical receptors that are found in both hairy skin and glabrous skin (hairless skin) include free nerve endings, pacinian corpuscles, Merkel disks, and Ruffini endings ( Pinel, 2000). These receptors have different functions and adapt to stimuli at different speeds. For example, under a constant pressure applied to the skin, the stimulus (pressure) evokes an activation of all receptors, but after a few hundred milliseconds, only the slow-adapting receptors remain active. This can explain why people are often unaware of some constant tactual stimuli. For instance, we are usually unaware of the feeling of our clothes against our body, or the glasses standing on our nose, unless we focus attention on them or move them consciously. Therefore, in order to identify objects by touch, dynamic manipulation is required so that the pattern of stimulation continually changes (Pinel, 2000). In other words, motion touch or dynamic touch is more effective than static touch in identifying object properties including textures. This is also the reason why in most of the experimental research for materials tactile experience, motive touch was adopted in the tests.

Touch can be divided into three main types: passive touch, active touch (Gibson, 1966), and intra-active touch (Bolanowski et al., 1999). Passive touch refers to a touch under the condition in which the subject is stationary and the stimulus is imposed upon the skin. Active touch refers to a touch under the condition in which the stimulus is stationary and the subject actively explores an object or surface. Intra-active touch, as an active/passive activity, means actively moving an object over another surface of the body which is stationary. Our interest is focused more on active touch, because in most cases, especially at the first contact with the product at the sales point, active touch may be more involved in the decision to purchase. Although early scholars used "tactile" for "passive touch" and "tactual" or "haptic" for active touch (William and Emerson, 1982), we tend to equalize these two terms.

Read full chapter

URL:

https://www.sciencedirect.com/science/article/pii/B9780080993591000035

goodwinequithere.blogspot.com

Source: https://www.sciencedirect.com/topics/engineering/tactile-perception

Post a Comment for "Skin Receptors Communicating the Sensation of Heavy and Continuous Touch and Pressure Are Known as"