This study aimed to obtain knowledge for improving usability through motion characteristics analysis based on peak velocity of drag on touch screens. We conducted an experiment in which an object was dragged to a target position. The drag direction and distance were adopted as experimental factors. Ten subjects participated in this study; their average age was 23.6 years. The results showed that the fingertip movement for drag corresponded well with the performance model based on Fitts’ law, and the usability decreased under the conditions with relatively long distance excepting the right direction. The peak velocity of dragging was almost linearly related to the distance to the target and was higher in the horizontal direction than in the vertical direction. Since the corrective movement for positioning at the target accounted for more than half of the drag movement, operation support for the corrective movement may improve usability.

<p>Hardness identification is one of the most important tactile senses in humans. People use their hands in various ways to identify the hardness of an object. For example, acupuncturists identify stiffness in a muscle by pressing down with their forefinger held flat over the affected area. However, experimental evidence for the role of the pressing method in the identification of an object's hardness even when the same finger is used has not been shown yet. In this fundamental study, we investigated the differential threshold of hardness for different finger postures of pressing (pressing down with one's forefinger held "flat" or "vertically") to determine the relationship between the different finger postures of pressing and hardness identification. We used seven elastic test pieces, each with a different Young's modulus, as the presented stimuli. We conducted an experiment using the constant method to calculate the differential threshold of hardness as a measure of hardness identification. The results showed that the differential threshold of hardness was higher when pressing down with a forefinger held "flat" than when pressing down "vertically" with the same force. This finding will be useful in evaluating the tactile identification of hardness in acupuncturists.</p>

Japanese Industry Standards (JIS) S 0021 (Packaging - Accessible Design - General Requirements) indicate the design policy for easy-to-use packaging and containers, targeting various individuals including elderly persons and individuals with disabilities. The JIS S 0021 includes tactile signs that are necessary to ensure the ease of distinguishing and handling as well as the ease of using those packaging and containers. The JIS S 0021 prescribes tactile signs on shampoo containers and notches for beverage paper packaging containers as tactile signs to distinguish the contents of the package and to differentiate between containers with the same or similar shapes. The policy was expanded to include tactile signs for body soaps when the standard was amended in 2014, and this was attributed to the fact that organizations of visually impaired demanded tactile signs for body soap, since body soap is often packaged in containers with shapes similar to those for shampoos and hair conditioners. Hence, tactile signs prescribed for body soap in JIS S 0021 guidelines were recently expanded to commercially available body soap containers. In the present study, experiments were performed to study the shapes of tactile signs for distinguishable body soap container. Specifically, shapes were studied through the following two steps: 1) tactile signs were selected based on experiments to evaluate the ease of distinguishing between multiple tactile signs, in a hearing survey involving visually impaired; and 2) experiments were performed to evaluate the tactile signs assuming that they were manufactured in collaboration with the Japan Cosmetic Industry Association, which is an industry organization of manufacturers for body soap and other products. It should be noted that the experiments involving distinguishing between products prioritized tactile signs on the top surfaces of the containers instead of on the side, since visually impaired tend to distinguish between pump containers by touching the top surfaces of the containers in hotels and public restrooms. The results of the experiments were used for tactile signs in the amended JIS S 0021 in 2014 for body soap. This study described evaluation experiments performed on the distinguishability of tactile signs on the top surfaces of pump type body soap containers to determine the factors that should be considered when establishing JIS tactile signs for body soap containers.

The purpose of this study was to identify the key joint kinematics characteristics during walking that related to Locomotive syndrome (LS) in order to develop some kind of device which can assess the risk of LS from gait on a daily basis. For this purpose, joint kinematics data during walking were obtained from 54 healthy community-dwelling elderly subjects (10 belong to LS). From these data, we calculated time-normalized lower limb joint angles on three planes during one gait cycle. For each time point, we also calculated averages and standard deviations of joint angles within the 5 trials. Principal component analysis (PCA) was conducted using input matrix made from the time–normalized lower limb joint angle kinematics (3 Planes × 3 Joints × 101 poins × 2 parameters). To determine Principal Component Vector (PCV) related to LS, we conducted t-tests on the Principal Component Scores of each PCV related to LS between LS group and non-LS group. To understand joint kinematics related to LS, we reconstructed them from each PCV related to LS. Among these PCVs, PCV 6 affect walking speed from hip and anlke joint angles point of view, and PCV 12 affect walking speed from cadence point of view. These PCVs revealed that LS group walks smaller walking speed than non-LS group. Further, PCV 9 related to ROM during walking on sagittal plane: LS group tended to showe smaller ROM than non-LS group. However, this PCV did not relate to spatiotemporal variables such as walking speed or step length. These findings suggest the possibility to develop some kind of sensor systems to assess LS using thesecharacteristics .

The vibrating conditions necessary for induction of the illusion of the metacarpophalangeal joint of index finger flex movement and the perceptual properties of the illusion itself were investigated in this study. The experimental factors were vibration frequencies of 50, 70, 90, 110, 130, 150, 170 and 190 Hz. Subjects were asked to evaluate the presence or absence of an illusion and its vividness on a 5-point scale. Simultaneously, the perceptual time it took for an illusion to occur from beginning vibration and the maximum illusory angle were measured. It was found that the occurrence rates and the vividness of the illusions were highest at the vibration frequencies of 70, 90, 110, and 130 Hz. The response time was about 5 seconds, and the maximum illusory angle was approximately 40 degrees. These findings could potentially be useful in developing a new interface device using kinesthetic sensation.

Identification of the hardness of an object in a human hand is different according to the hardness of the object. For example, chiropractors identify stiffness in the muscle by using their thumb, which can press more forcefully than the forefinger. However, it has not been shown experimentally if the characteristics of hardness discriminability are different according to fingers. In this study, to clarify the relation between different fingers pressing elastic objects and the characteristics of hardness discriminability, we investigated the differential threshold of hardness using the forefinger and thumb. Additionally, the influence of press force and press displacement on the characteristics of hardness discriminability was clarified. We used 7 elastic test pieces with different Young's moduli as the presented stimuli. We also used the test pieces with hardness sensation judged as 'hard' in our previous research. We conducted the experiment using the constant stimuli method to calculate differential threshold of hardness as one evaluation index of hardness discriminability when using the forefinger and thumb. The results of this experiment showed that the hardness discriminability of the thumb was better than that of the forefinger. In addition, these results suggested that press displacement but not press force should be used to estimate the hardness discriminability and that the thumb is better than the forefinger to discriminate the displacement. These findings clarify the mechanism underlying hardness discriminability in the human hand.

Identification of the hardness of an object in a human hand is different according to the hardness of the object. For example, chiropractors identify stiffness in the muscle by using their thumb, which can press more forcefully than the forefinger. However, it has not been shown experimentally if the characteristics of hardness discriminability are different according to fingers. In this study, to clarify the relation between different fingers pressing elastic objects and the characteristics of hardness discriminability, we investigated the differential threshold of hardness using the forefinger and thumb. Additionally, the influence of press force and press displacement on the characteristics of hardness discriminability was clarified. We used 7 elastic test pieces with different Young's moduli as the presented stimuli. We also used the test pieces with hardness sensation judged as 'hard' in our previous research. We conducted the experiment using the constant stimuli method to calculate differential threshold of hardness as one evaluation index of hardness discriminability when using the forefinger and thumb. The results of this experiment showed that the hardness discriminability of the thumb was better than that of the forefinger. In addition, these results suggested that press displacement but not press force should be used to estimate the hardness discriminability and that the thumb is better than the forefinger to discriminate the displacement. These findings clarify the mechanism underlying hardness discriminability in the human hand.

The satisfactory vibrating conditions and the perceptual properties of inducing illusory horizontal shoulder flexion were investigated in this study. The experimental factors were the vibration frequencies of 30, 50, 70, 90, 110, and 130 Hz. We subjectively assessed the presence or absence of an illusion and its vividness on a 5-point scale. Simultaneously, the perceptual time it took for an illusion to appear and the maximum illusory angle was measured. It was found that the maximum occurrence rate of the illusion was 98% at a vibration frequency of 70, 90, 110 Hz. The illusory angle was approximately 30°. It took 7s for an illusion to appear. Based on this knowledge, we plan to develop an interface device that will provide kinesthetic sensations only without the actual motion in a future study. This device could potentially be used for tactile feedback technology in the virtual reality space.

The satisfactory vibrating conditions and the perceptual properties of inducing illusory horizontal shoulder flexion were investigated in this study. The experimental factors were the vibration frequencies of 30, 50, 70, 90, 110, and 130 Hz. We subjectively assessed the presence or absence of an illusion and its vividness on a 5-point scale. Simultaneously, the perceptual time it took for an illusion to appear and the maximum illusory angle was measured. It was found that the maximum occurrence rate of the illusion was 98% at a vibration frequency of 70, 90, 110 Hz. The illusory angle was approximately 30°. It took 7s for an illusion to appear. Based on this knowledge, we plan to develop an interface device that will provide kinesthetic sensations only without the actual motion in a future study. This device could potentially be used for tactile feedback technology in the virtual reality space.

This paper presents a novel sports training system. We developed a visual real-time feedback system that directly transmits a bird's eye view from a drone camera to a player's eyes. Individual physical ability, experience and intuition is important; however, in team sports such as baseball, football and volleyball, players need to perform spatial cognition such that they immediately understand where they, their teammates and their opponents are on the field as if they could see it from a bird's eye view. The objective is to validate the feasibility of the bird's eye view feedback system. In an experiment, nine participants moved and stood between two experimenters as a cut-off man with or without the system. Using the system produced significantly less error than with no system (p < 0.05). In conclusion, this bird's eye view feedback system can improve human spatial cognition.

Braille is a well-known communication tool for the visually impaired. In recent years, as a result of advances in Braille printing technology, the use of transparent resinous ultraviolet cured type (TRUCT) Braille has spread rapidly. As one of the most popular Braille printing technologies, the screen printing method is applied for printing TRUCT Braille. However, the screen printing method produces TRUCT Braille prints of poor quality. In this study, in order to improve the printing quality, we created a device for printing TRUCT Braille. Additionally, we evaluated TRUCT Braille readability for Braille beginner readers by focusing on horizontal and vertical Braille dot distances using our created device. From this study, we found that it was easy to print TRUCT Braille using our device. Braille beginner readers found it easy to read TRUCT Braille with adequate horizontal and vertical Braille dot distances. These findings support the use of TRUCT Braille for new Braille beginner textbooks, as well as for printing Braille signs in public facilities.

The portability of touch-sensitive screen tablets provides high usability under various circumstances, and such tablets are increasingly utilized in the education and other fields. Meanwhile, the design of the graphical user interface (GUI) of such tablets requires careful consideration in order not to lose tablet operability in such diverse situations. In this study, we conduct an experiment to investigate the effect that touch-sensitive screen button size and spacing have on operability, while considering the influence of the angle that the forefinger makes when touching the screen. As a result, we could determine the conditions required for the size and spacing of buttons to allow fast and accurate operation independent of contact angle. Furthermore, we could reveal the relationship between contact angle and area, and investigate the impact of the contact angle when touching smaller buttons.

Braille is a well-known communication tool for the visually impaired. In recent years, as a result of advances in Braille printing technology, the use of transparent resinous ultraviolet cured type (TRUCT) Braille has spread rapidly. As one of the most popular Braille printing technologies, the screen printing method is applied for printing TRUCT Braille. However, the screen printing method produces TRUCT Braille prints of poor quality. In this study, in order to improve the printing quality, we created a device for printing TRUCT Braille. Additionally, we evaluated TRUCT Braille readability for Braille beginner readers by focusing on horizontal and vertical Braille dot distances using our created device. From this study, we found that it was easy to print TRUCT Braille using our device. Braille beginner readers found it easy to read TRUCT Braille with adequate horizontal and vertical Braille dot distances. These findings support the use of TRUCT Braille for new Braille beginner textbooks, as well as for printing Braille signs in public facilities.

The portability of touch-sensitive screen tablets provides high usability under various circumstances, and such tablets are increasingly utilized in the education and other fields. Meanwhile, the design of the graphical user interface (GUI) of such tablets requires careful consideration in order not to lose tablet operability in such diverse situations. In this study, we conduct an experiment to investigate the effect that touch-sensitive screen button size and spacing have on operability, while considering the influence of the angle that the forefinger makes when touching the screen. As a result, we could determine the conditions required for the size and spacing of buttons to allow fast and accurate operation independent of contact angle. Furthermore, we could reveal the relationship between contact angle and area, and investigate the impact of the contact angle when touching smaller buttons.

Touch-sensitive screen terminals enabling intuitive operation are used as input interfaces in a wide range of fields. Tablet terminals are one of the most common devices with a touch-sensitive screen. They have a feature of good portability, enabling use under various conditions. On the other hand, they require a GUI designed to prevent decrease of usability under various conditions. For example, the angle of fingertip contact with the display changes according to finger posture during operation and how the case is held. When a human fingertip makes contact with an object, the contact area between the fingertip and contact object increases or decreases as the contact angle changes. A touch-sensitive screen detects positions using the change in capacitance of the area touched by the fingertip; hence, differences in contact area between the touch-sensitive screen and fingertip resulting from different forefinger angles during operation could possibly affect operability. However, this effect has never been studied. We therefore conducted an experiment to investigate the relationship between size/spacing and operability, while taking the effect of fingertip contact angle into account. As a result, we have been able to specify the button size and spacing conditions that enable accurate and fast operation regardless of the forefinger contact angle.

<p>Tactile raised characters are useful in creating accessible designs for the benefit of people with acquired visual impairment. For instance, tactile raised characters are used on elevator buttons and television remote controls as an assistive tool based on the philosophy of accessible design. However, sufficient reliable data on the appropriate size for perception of such characters are not available. In this study, we investigated the influence of the size of tactile raised Arabic number characters (0 through 9) on their perceptibility using two experimental designs. One experiment involved young and old individuals with normal vision who were unfamiliar with the systems intended for people with acquired visual impairment, the other experiment was for young and old visually impaired persons. The tactile raised characters were presented one by one in random order using our developed experimental apparatus. There was a correlation between the size of the tactile raised characters and their perceptibility. This knowledge will be useful in discussing revisions to the Japanese Industrial Standard regarding tactile raised characters or in formulating new guidelines pertaining to tactile substitution tools.</p>

<p>Touch-sensitive screens that serve as displays and input devices have been adopted in many portable terminals such as smartphones and personal media players, and this market has expanded greatly. A feature of touch-sensitive screens is that their graphical user interface (GUI) can be designed arbitrarily. However, it has been pointed out that GUIs may be difficult to use if the designer is unfamiliar with human operational characteristics. This is because there is insufficient knowledge about the operational characteristics of humans. Therefore, in this study, we aimed to evaluate the characteristics of pointing when using portable terminals with touch-sensitive screens, and we conducted an experiment to obtain knowledge that can be used in the design of easy-to-use GUIs. In this experiment, we evaluated the characteristics of pointing by measuring the distributions of the pointing positions and pointing time. The subjects who participated in the experiment were asked to operate a portable terminal with a touch-sensitive screen under three operational conditions. The results showed that the pointing position distribution depended on the target display area in all operational conditions. We also found that the pointing time was better in the areas that the thumb could reach without extension or flexing during one-handed operations. Furthermore, we describe an effective approach for designing an ellipsoid touch-sensitive area based on the pointing position distribution determined in this experiment. We also evaluated the effectiveness of this new design approach.</p>

<p>The Japanese Standards Association (2000) and the International Organization for Standardization (2011) have standardized tactile bars (bar-shaped symbol on a stop key) and dots (dot-shaped symbol on a start key) that enable people with visual impairment to discriminate the keys on consumer products. However, to the best of our knowledge, there have been no studies regarding their recommended sizes and shapes in view of the establishment and modification of standards related to tactile bars and dots. The purpose of this study is to evaluate the influence of the sizes of tactile dots and bars on their discriminability to determine the appropriate size of tactile bars (as distinguished from tactile dots) regardless of the aging and tactile experiences, which markedly affect tactile acuity on the fingertips. Younger and older participants with or without visual impairment tactually discriminated tactile dots and bars presented individually, in random order, via a two-alternative forced-choice task. The results showed that participants discriminated tactile bars from tactile dots faster and more accurately as the dimensional difference between the bar length and width increased. In particular, younger sighted, younger, and older blind participants distinguished tactile bars of more than +2.0 [mm] length from tactile dots correctly. However, the older sighted participants required a bar length of +3.0 [mm] for accurate discrimination of tactile bars. In addition, younger and older sighted persons discriminated tactile bars with a length of +4.0 [mm] in less time, whereas younger and older blind participants were able to discriminate tactile bars of more than +3.0 [mm] length. On the other hand, tactile dots with a larger edge radius of curvature have higher discriminability than tactile dots with a smaller edge radius of curvature for dots of identical height.</p>

Recently, many tactile guide maps have been installed at various public facilities. Tactile guide map designers have used raised dot patterns to express drawings on a tactile guide map. However, we are lacking quantitative data regarding raised dot patterns for the design of easily understandable tactile maps. In this study, we investigated the influence of dot distances on discrimination of dot patterns used in tactile guide maps by conducting an experiment to find highly discriminable combinations of dot patterns by comparing pairs of dot patterns. The results showed that combinations of dot patterns with a larger difference in dot distances had higher discriminability. When the differences were the same, the combinations of wider dot distances had lower discriminability. Dot patterns with more than 5.0 mm differences in dot distances were highly discriminable for sighted persons, whereas those with more than 4.0 mm differences were highly discriminable for blind persons.

We investigated optimal vibrating conditions for inducing illusory elbow extension movement to develop various practical applications. The experimental factors were the vibration frequency (30, 50, and 70 Hz), vibration amplitude (three phases for each frequency condition), and contact press force (3, 5, 7, 9 N). We subjectively assessed the presence or absence of an illusion, and the vividness on a five-point scale. The results of this study showed that when the vibration amplitude and contact press force became higher than certain values at vibration frequencies of 50 or 70 Hz, the illusion was produced for 80% or more participants, and the vividness of the illusion was increased. Under these stimulation conditions, illusory elbow extension movement can be easily produced; we can develop an interface device that will only provide kinesthetic sensations without the actual motion. Such an interface device can be used for rehabilitation and education fields, and gaming devices.

Recently, touch-sensitive screens have been used for various devices: smartphones, slate PCs, personal media players, etc. Specifically, tablet terminals with a touch-sensitive screen have spread rapidly in the fields of education, medicine, business, etc. However, it has been pointed that their operability is influenced by the difficulty in sliding a fingertip. This study is aimed at examining the influence of the surface condition of the display on the operability of tablet terminals. We measured the coefficients of kinetic friction between the tip of the forefinger and several screen protection films. Our measurements indicate that the coefficient of kinetic friction of anti-glare (AG) film was about one-third that of hard coat (HC) film. Then, we conducted an experiment using these films to evaluate the relationship between the surface condition of the display and the operability. The results show that the surface condition of the display influences the accuracy and speed of operation.

Raised striped-pattern has been used as a drawing expression of tactile guide map. We are lacking in quantitative data regarding raised striped-pattern for designing easily understandable tactile map. In this study, we investigated the influence of interstices among the lines on tactile discriminability of raised striped-pattern. Ten younger persons and thirteen older ones were asked to distinguish the surface roughness according to 4 categories by comparing 10 raised striped-patterns of different interstices among the raised lines, which were prepared on the basis of the results of previous study. From this study, we found that 5.0mm interstice was necessary for distinguishing different surface roughness and those older persons were somewhat inferior to younger persons in sensitivity of surface roughness.

This study focused on the features of the perceived foot heights which could be a factor of the risk of tripping during walking. We measured and evaluate the errors between the perceived foot heights and actual foot heights. Ten young adults, whose lower visual fields were occluded, were asked to adjust their toe height to the height of the target test-piece that placed on the floor 3[m] ahead of them. Once they felt that their toe height was appropriately matched to the target height, the distance between their toe and the target height was measured, and compared the constant errors among the conditions (height of the test-pieces and dominant limb). The amount of the constant error tended to increase in negative direction. Moreover, such features were consistent with the features of the joint position senses that reported previously. These results indicate that as the participants raise their toe higher, the heights of their toe tend to become lower than they expected.

This study focused on the features of the perceived foot heights which could be a factor of the risk of tripping during walking. We measured and evaluate the errors between the perceived foot heights and actual foot heights. Ten young adults, whose lower visual fields were occluded, were asked to adjust their toe height to the height of the target test-piece that placed on the floor 3[m] ahead of them. Once they felt that their toe height was appropriately matched to the target height, the distance between their toe and the target height was measured, and compared the constant errors among the conditions (height of the test-pieces and dominant limb). The amount of the constant error tended to increase in negative direction. Moreover, such features were consistent with the features of the joint position senses that reported previously. These results indicate that as the participants raise their toe higher, the heights of their toe tend to become lower than they expected.

Recently, touch-sensitive screens have been used for various devices: smartphones, slate PCs, personal media players, etc. Specifically, tablet terminals with a touch-sensitive screen have spread rapidly in the fields of education, medicine, business, etc. However, it has been pointed that their operability is influenced by the difficulty in sliding a fingertip. This study is aimed at examining the influence of the surface condition of the display on the operability of tablet terminals. We measured the coefficients of kinetic friction between the tip of the forefinger and several screen protection films. Our measurements indicate that the coefficient of kinetic friction of anti-glare (AG) film was about one-third that of hard coat (HC) film. Then, we conducted an experiment using these films to evaluate the relationship between the surface condition of the display and the operability. The results show that the surface condition of the display influences the accuracy and speed of operation.

Tactile dots (dot-shaped tactile symbols) placed on the operation keys of consumer products such as cellular phones contribute to improving accessibility for everyone, including persons with visual impairment. JISC (Japanese Industrial Standards Committee) and ISO (International Organization for Standardization) standardized tactile dots and bars. However, sufficient reliable data on the appropriate sizes and cross-section shapes of tactile dots and bars was not necessarily available. Therefore, more quantitative data for optimal dimensions of tactile dots and bars is required to revise existing standards and devise new standards. In this paper, we evaluated influences of the height (0.1, 0.3, 0.55 and 0.75 mm, without tactile dot) and the tip radius of curvature (0.1, 0.3, 0.5, 0.7 and 0.9 mm) of tactile dots on the operational performance in cellular phones. 16 sighted younger participants, whose hand was covered by a curtain, were asked to operate cellular phones with a tactile dot on its key 5 and without tactile dots. As the result, both too high and low height dots are not effective to improve the operational performance of cellular phones and there is an appropriate range of the height of tactile dots regardless of the tip radius of curvature. Furthermore, participants performed better at a particular height with larger tip radius of curvature.

<p>In 2000, Japanese Standards Association standardized tactile dots and bars on consumer products for all people, including older people and people with disabilities. However, the numerical values for the size of tactile dots and bars were not determined on the basis of reliable data. The purpose of this study is to evaluate the relationship between input methods (the two-handed forefinger input and the one-handed thumb input) and the influence of the height of tactile dots (i.e., 0.0, 0.1, 0.3, 0.5, and 0.7 mm) on input performance when operating cellular phones. To analyze the influence of the height of tactile dots for each input method, we compared the results for the two-handed forefinger method from this study and that for the one-handed thumb method from our previous study. Normal sighted young and old participants, whose hands were covered by a curtain, operated cellular phones with a tactile dot on key 5 and other phones without a tactile dot. They operated the numerical keypad with the forefinger or the thumb while looking at 50 randomly ordered Arabic numbers one at a time. As a result of the experiments, both group of participants performed better with a tactile dot, rather than without it, using each input method, and they could operate more accurately and quickly especially in the case of a 0.3 mm high dot. On the other hand, by using the one-handed thumb method, the input performance deteriorated when the tactile dot was higher than 0.3 mm. However, by using the two-handed forefinger method, the input performance did not deteriorate as the height of the tactile dot was increased. This result was attributed to the differences in operating characteristics between one-handed and two-handed input methods.</p>

:Tactile dots and bars serve as tactile landmarks so that people with visual impairment can use same consumer products as those used by sighted people. However, reliable age-related data on the appropriate sizes and the shapes was not necessarily available. The purpose of this study is to evaluate influences of edge radius of curvature of tactile dots and bars on their discriminability in younger and older people to determine the appropriate size of tactile bars (as distinguished from tactile dots). Sighted younger and older participants tactually discriminated the tactile dots and bars presented individually, in random order, by a two-alternative forced-choice task. The results showed that both participants discriminated tactile bars from tactile dots faster and more accurately as the dimensional difference between bar length and width increased, regardless of conditions of edge radius of curvature. Therefore, longer dimensional difference between width and length of tactile bars is an important factor to discriminate tactile bars correctly. On the other hand, tactile dots with a larger edge radius of curvature have higher discriminability than tactile dots with a smaller edge radius of curvature in the case of dots of identical height.

:Tactile dots located on operation keys of consumer products such as cellular phones contribute to improving accessibility for older people and people with visual impairment. The Japanese Standards Association (2000) and the International Organization for Standardization (2011) standardized tactile dots. However, reliable data on the appropriate sizes and the shapes was not necessarily available. The purpose of this study is to evaluate influences of the height (0.1, 0.3, 0.55, and 0.75 mm) and the tip radius of curvature (0.1, 0.3, 0.5, 0.7, and 0.9 mm) of tactile dots on the operational performance of cellular phones in younger and older people. Sighted younger and older participants, whose hand was covered by a curtain, operated cellular phones with a tactile dot on its key 5 and without a tactile dot. As the result, both participants performed better at a particular height with larger tip radius of curvature. Furthermore, older participants operated better at high dots like 0.55-0.75 mm. In contrast, younger participants performed better at 0.3 mm and relatively poorly at 0.1 mm and 0.75 mm. Thus, comparatively high tactile dots are useful for improving the accessibility of products for the older and there is an appropriate height range for the younger.

Tactile dots (dot-shaped tactile symbols) placed on the operation keys of consumer products such as cellular phones contribute to improving accessibility for everyone, including persons with visual impairment. JISC (Japanese Industrial Standards Committee) and ISO (International Organization for Standardization) standardized tactile dots and bars. However, sufficient reliable data on the appropriate sizes and cross-section shapes of tactile dots and bars was not necessarily available. Therefore, more quantitative data for optimal dimensions of tactile dots and bars is required to revise existing standards and devise new standards. In this paper, we evaluated influences of the height (0.1, 0.3, 0.55 and 0.75 mm, without tactile dot) and the tip radius of curvature (0.1, 0.3, 0.5, 0.7 and 0.9 mm) of tactile dots on the operational performance in cellular phones. 16 sighted younger participants, whose hand was covered by a curtain, were asked to operate cellular phones with a tactile dot on its key 5 and without tactile dots. As the result, both too high and low height dots are not effective to improve the operational performance of cellular phones and there is an appropriate range of the height of tactile dots regardless of the tip radius of curvature. Furthermore, participants performed better at a particular height with larger tip radius of curvature.

To determine the effects of aging on the accuracy of perceived foot position, we conducted following experiment to 10 elderly and 10 young participants. Participants were asked to adjust the position of the target line as close as possible to either most medial or most lateral parts of their foot, while they wore a modified cape that obscured their view of their feet. Once they felt that target line was appropriately placed along the foot, the distance between the line and the foot was measured. No age-related differences were identified when they were asked to place the line along with the most lateral part of their foot. Both age groups tended to place the line 10-20 mm over the foot. However, the elderly displayed smaller errors than young when they were asked to place the line along with the most medial part of their foot. We also discussed the possible reasons that explain these features in the article.

Recently, Transparent-resinous-ultraviolet-curing-type Braille (TRUCT Braille) signs have been spread. However, it has said that TRUCT Braille reading is affected by the friction between forefingers' slipperiness to TRUCT Braille' readability. In previous study, for the purpose of decreasing this friction and enhancing TRUCT Braille readability, we invented a assistive tool of Braille Reading made by polyester non-woven fabric and found that old people with visual impairment wearing it enhances the reading speed and error rate of TRUCT Braille. However, we had to review its material and discuss the fabrication approach. In this study, we compared several materials with polyester non-woven fabric. As a result, we found that sateen weave fabric is better for assistive tool of Braille Reading because of its softness and slipperiness. And we invented fabrication approach of assistive tool of Braille Reading and made its test production.

To determine the effects of aging on the accuracy of perceived foot position, we conducted following experiment to 10 elderly and 10 young participants. Participants were asked to adjust the position of the target line as close as possible to either most medial or most lateral parts of their foot, while they wore a modified cape that obscured their view of their feet. Once they felt that target line was appropriately placed along the foot, the distance between the line and the foot was measured. No age-related differences were identified when they were asked to place the line along with the most lateral part of their foot. Both age groups tended to place the line 10-20 mm over the foot. However, the elderly displayed smaller errors than young when they were asked to place the line along with the most medial part of their foot. We also discussed the possible reasons that explain these features in the article.

Recently, many tactile guide maps have been installed at various public facilities with the enactment of "Barrier Free New Law". In tactile guide maps, some tactile symbols have been used for indicating some information items. Japanese Standards Association enacted Standardized Method of Displaying Tactile Guide Maps March 2007 (JIS T0922). Tactile symbols shapes are regulated by the JIS. However, other components of tactile symbol (such as edge, size etc) are unregulated because there are no sufficient research achievements regarding tactile symbols. In this study, for the purpose of investigating influence of tactile symbols edge clarity on their tactile symbols, we compared tactile symbols discriminability in two conditions with tactile symbol edge clarities (acute type (cutting method) and gentle type (screen printing method)). We made tactile symbol test pieces with various sizes by the two methods. And twelve older participants and twelve younger participants were asked to discriminate tactile symbol test pieces. From this study, we found the relation between tactile symbols edge clarity and discriminability of tactile symbols. It was also found that tactile symbols edge clarity influence on their discriminability when the size was particularly small.

To determine the effects of aging on the accuracy of perceived foot position, we conducted following experiment to 10 elderly and 10 young participants. Participants were asked to adjust the position of the target line as close as possible to either most medial or most lateral parts of their foot, while they wore a modified cape that obscured their view of their feet. Once they felt that target line was appropriately placed along the foot, the distance between the line and the foot was measured. No age-related differences were identified when they were asked to place the line along with the most lateral part of their foot. Both age groups tended to place the line 10-20 mm over the foot. However, the elderly displayed smaller errors than young when they were asked to place the line along with the most medial part of their foot. We also discussed the possible reasons that explain these features in the article.

Recently, many tactile guide maps have been installed at various public facilities with the enactment of "Barrier Free New Law". In tactile guide maps, some tactile symbols have been used for indicating some information items. Japanese Standards Association enacted Standardized Method of Displaying Tactile Guide Maps March 2007 (JIS T0922). Tactile symbols shapes are regulated by the JIS. However, other components of tactile symbol (such as edge, size etc) are unregulated because there are no sufficient research achievements regarding tactile symbols. In this study, for the purpose of investigating influence of tactile symbols edge clarity on their tactile symbols, we compared tactile symbols discriminability in two conditions with tactile symbol edge clarities (acute type (cutting method) and gentle type (screen printing method)). We made tactile symbol test pieces with various sizes by the two methods. And twelve older participants and twelve younger participants were asked to discriminate tactile symbol test pieces. From this study, we found the relation between tactile symbols edge clarity and discriminability of tactile symbols. It was also found that tactile symbols edge clarity influence on their discriminability when the size was particularly small.

In this study, we developed a sound tactile interface that makes use of the human sensation of hardness. The interface comprises eight elastic objects having varying degrees of hardness. Each elastic object is shaped like a column. When a teacher or a child presses each elastic object, different funny sounds are produced depending on the hardness of the elastic object. The types of sounds used were "Do Re Mi sounds" and "Animal call sounds." We can switch between sound modes using a wireless remote control. The interface has a major advantage in that both healthy children and handicapped children can play with it together. In this paper, we would like conference participants to experience this interface.

Present study focused on the effect of approaching directions for stepping over an obstacle. Ten young adults were asked to head towards an obstacle from seven directions (+60, +40, +20, 0, -20, -40, and -60 degrees), and step over it. In each trial, one of the three obstacles with different heights (25mm, 50mm, and 150mm) were placed. Participants repeated the movement against each obstacle condition 5 times for a total of 105 trials. Kinematics while the participants step over the obstacles were recorded using 3-D motion capturing system, and were compared using the following parameters among the conditions: toe clearances, step length, step width, and walking speed. The results revealed that the approaching direction to the obstacles does not critically affect the obstacle avoidance movement in regards to tripping, but may critically affect the movements in regards to loss-of-balance.

Present study focused on the effect of approaching directions for stepping over an obstacle. Ten young adults were asked to head towards an obstacle from seven directions (+60, +40, +20, 0, -20, -40, and -60 degrees), and step over it. In each trial, one of the three obstacles with different heights (25mm, 50mm, and 150mm) were placed. Participants repeated the movement against each obstacle condition 5 times for a total of 105 trials. Kinematics while the participants step over the obstacles were recorded using 3-D motion capturing system, and were compared using the following parameters among the conditions: toe clearances, step length, step width, and walking speed. The results revealed that the approaching direction to the obstacles does not critically affect the obstacle avoidance movement in regards to tripping, but may critically affect the movements in regards to loss-of-balance.

The feel of Braille and Braille readability vary according to the type of Braille output used. In this study, we have developed a model for measuring the 3D cross-sectional shape and size of Braille characters. We measured the sizes of Braille characters printed by three Braille output devices. These devices were made in three countries, namely, Japan, the United States, and Germany. We have also developed a tangible and 3D enlarged Braille model for understanding the relationship between a Braille output device and the 3D cross-sectional shape of the Braille characters outputted by it. This model was displayed at Braille-Big-Event to commemorate the 200th anniversary of the birth of Louis Braille-the inventor of the Braille coding system. Over 200 visitors at this event could easily identify the difference in the 3D cross-sectional shape of Braille characters outputted by different Braille output devices.

When children who have the movement disorder try to operate the computer, the operation is difficult in a general keyboard and the mouse. Then, the scanning input with the equipment and the switch of an alternate key board and an alternative mouse have been applied. Then we studied of what kind of setting when communication assistance for persons with physical disability by use of eye tracking device.

<p>Tactile sense is the third most important sense after visual sense and hearing sense. Recently, cognitive psychology studies on tactile illusions have gained attention because of the potential applications of such sensations in tactile displays and interfaces. In this study, we focused on a unique and interesting sensation called "velvet tactile illusion," and we examined the possibility of creating this illusion by passive touch. We investigated the relationship between some factors related to the creation of this illusion and the percentage of creating the illusion by passive touch. We then developed a device to evaluate the creation of this illusion by passive touch. This device can control factors such as line movement velocity, line diameter, and line distance that influence the creation of the velvet tactile illusion. Using this device, we conducted exhaustive tests for different values of these factors. In addition, we conducted an experiment to examine the influence of some factors on the creation of velvet tactile illusion by passive touch. The relationship between some factors related to the creation of this illusion and condition of creating the illusion was found. These data will be helpful data when we develop the new tactile display regarding velvet tactile illusion.</p>

In 2000, a new standard (Japanese Industrial Standard, JIS S 0011) was enacted in Japan. The standard provided the perceptual sizes of tactile dots and bars for use in consumer products. However, the numerical values about these sizes were not determined based on data reliable enough. Therefore, objective and quantitative data for perceptual sizes of tactile dots and bars is required for revising this JIS and for devising other standards. In this study, we focused attention on cellular phones becoming common around the world and evaluated the influence of the height of tactile dots (0.0, 0.1, 0.3, 0.5 and 0.7[mm]) on the operational performance of cellular phone. In this experiment, each 20 sighted younger and older participants, whose hand was covered by a curtain, was asked to operate cellular phones with tactile dot on its key 5 and without tactile dot. Both groups performed better with a tactile dot than without it. However, with a dot height of 0.7mm, participants felt significant pain. We determined that there is an appropriate range of the height of tactile dot that improves the operational performance of cellular phones.

In 2000, a new standard (Japanese Industrial Standard, JIS S 0011) was enacted in Japan. The standard provided the perceptual sizes of tactile dots and bars for use in consumer products. However, the numerical values about these sizes were not determined based on data reliable enough. Therefore, objective and quantitative data for perceptual sizes of tactile dots and bars is required for revising this JIS and for devising other standards. In this study, we focused attention on cellular phones becoming common around the world and evaluated the influence of the height of tactile dots (0.0, 0.1, 0.3, 0.5 and 0.7[mm]) on the operational performance of cellular phone. In this experiment, each 20 sighted younger and older participants, whose hand was covered by a curtain, was asked to operate cellular phones with tactile dot on its key 5 and without tactile dot. Both groups performed better with a tactile dot than without it. However, with a dot height of 0.7mm, participants felt significant pain. We determined that there is an appropriate range of the height of tactile dot that improves the operational performance of cellular phones.

A tactile map is an assistive tool for visually impaired persons to obtain special information. As new barrier-free laws were recently enacted in Japan, many Braille signs and tactile guide maps have been installed in various facilities. Several production methods are available for tactile guide maps. Screen prints have become increasingly popular in Japan because they offer several advantages, including the fact that they can be printed together with visual characters. However, users have one major complaint: screen printing does not create lines and dots on tactile maps, thus necessitating improvement in screen printing performance. In this study, we developed a new tactile map production device as an alternative to screen printing devices. Also, a tactile map created by our method included a vocal guidance function based on users&apos; needs. We found that the finished-print performance and convenience of tactile maps improved considerably. This study will be useful in providing a new style for future tactile maps.

When touching an object, the forefinger pad is deformed based on the hardness of the object, and we consider that slight deformation influences hardness sensation. To clarify the influence of deformation of forefinger pad on hardness sensation, we compared hardness sensation in two conditions with different deformation of the forefinger pad by the method of successive categories. Fourteen elastic test pieces with different hardness were evaluated by eleven subjects based on seven stages of hardness sensations (extremely soft, fairly soft, slightly soft, neither, slightly hard, fairly hard, extremely hard) for the conditions of direct touching of test pieces or touching using an acrylic plate. This results indicated that subjects were capable of perceiving slight differences in hardness within three categories (fairly soft, slightly soft, and fairly hard) for direct rather than indirect touch. Deformation of the forefinger pad based on the hardness of an object may thus influence hardness sensation when the hardness of an elastic object is classified into these three categories.

This study examined how accurately people can discriminate differences in the friction of flooring samples. Flooring samples of either different friction or elasticities were presented by placing two walking boards made of plywood, each surfaced with one of three different flooring samples, in an end-to-end fashion. Ten young adults whose sight was temporarily cut off by eye masks were asked to walk on the path for 108 trials and indicate whether the flooring samples were different or not. Generally, the percentages of correct answers for the pairs of flooring samples with different frictions were low compared with the percentages of correct answers for the pairs of flooring samples with different elasticity. However, the subjects who scuffed their heel on the ground prior to step on to the samples discriminated the differences fairly accurately, even for the materials with different frictions.

"Barrier-free New Law" was recently enacted in Japan. Therefore, many Braille signs and tactile guide maps have been installed at various buildings, stations and other public facilities. However, many unsatisfactory tactile guide maps appeared around us. Therefore, Japanese Standards Association enacted Standardized Method of Displaying Tactile Guide Maps in March 2007. However, rules and regulations about perception of texture with dot pattern and striped pattern for tactile guide maps were not contained. In this study, for the purpose of proposing useful texture with striped pattern for tactile maps, we examined the perception of texture with dot pattern and striped pattern on human forefinger. We made dot pattern and striped pattern test pieces with varying dot-distance and line-distance by screen-printing and asked ten subjects to clarify texture with striped-pattern (such as high density and low density) by the method of successive categories. As these results indicate, relation between dot and line distance and "perception of texture with dot pattern and striped pattern" on human forefinger became clear.

Recently, environment that visually impaired persons are capable of getting electric information is being developed. By using Braille display, visually impaired can get various electrical information on network. Therefore, Braille display rapidly spread in the foreign and domentic country. However, when Braille display is used continually, the base material of Braille display becomes worn. It has been pointed out that Braille readers find it difficult to read Braille on worn base material which their forefingers cannot slide easily. In this study, to reduce this friction, we reinvent a thin low friction film cover on worn base material to reduce friction during Braille reading. And also we carried out a study to investigate influence of base material features of Braille display on Braille reading and the effect of its use. We compared the discriminability of Braille when covering two films with excessive and less kinetic friction on the base material. As the results, subjects could read Braille significantly faster and more correctly when less kinetic friction film (powder compounded film) cover was used on the base material. In short, by use of powder compounded film cover, we found that Braille readers' forefingers can slide easily and discriminability of Braille was improved. From this study, we suggest the covering less friction this film on Braille display with worn base material as method of being able to improve the discriminability of Braille.

Tactile ground surface indicators installed on sidewalks help visually impaired people walk safely. However, these indicators could be an extra barrier for people who do not use those indicators. In previous study, we suggest that a functional leg length discrepancy while walking on the indicators is one of the reasons for the extra movements of the lower extremities for young. This study examines the effects of these indicators to the elderly comparing the kinematic and kinetic variables of walking on 1) a path without indicators, 2) a path with normally installed indicators, and 3) a path with recessed indicators. The results suggest that walking on the normally installed indicators causes extra movements of the lower extremities such as increased minimum toe heights during the mid-swing phase by raising entire lower extremities, and functional leg length discrepancy while walking on the indicators is one of the reasons for the extra movements of the lower extremities.

To determine the effects of nonlevel obstacles on obstacle-avoidance movements, young adults were asked to step over obstacles with various angles and heights, and the gaits were collected by using 3D motion capture system VICON-512. From the collected data, we defined the distance between the marker placed on the 5th metatarsal and the obstacle as "Lateral Toe Clearances" and the distance between the marker placed on the 1st metatarsal and the obstacle as "Medial Toe Clearances", and compared among leveled-obstacles and tilted-obstacles. There were no significant differences in lateral toe clearances among the leveled-obstacles of varying heights. However, the lateral toe clearances significantly decreased when stepping over the tilted-obstacles, compared to the leveled-obstacles. These results suggest that when people step over tilted-obstacles, they cannot raise their feet as much as they do when they step over leveled-obstacles, causing an increase in the chance of stumbling.

Transparent-resionous-ultraviolet-curting-type Braille (TRUCT Braille) signs are have spread rapidly for printing Braille together with visual characters on various base materials. However, it is not easy to read when printed on base material on which it is difficult for the forefinger to slide. The purpose of this study is to examine the influence of base materials on the TRUCT Braille reading. We used fine paper and laminate film as the base material, and measured coefficient of kinetic friction between forefinger and their base materials. The coefficient of kinetic friction for fine pape...

Recently, Transparent-resinous-ultraviolet-curing-type Braille (TRUCT Braille) signs have gained popularity in Japan for printing Brailles together with visual characters and they can be printed on the various base materials on which Braille dots are printed. However, it has been pointed out that TRUCT Braille reading is affected easily by the friction between the forefinger and the base material. In this study, for the purpose of investigating the effect of the forefingers' slipperiness to TRUCT Brailles' discriminability, we compare their discriminability with and without wearing the finger cover. We attempted a use of finger cover made by plain-weaved nylon to reduce the friction. The reason why we chose the nylon is its durability and its ability to absorb moisture that enlarges the friction. The participants of this experiment are beginners of Braille reading with normal vision. They were asked to discriminate 6 TRUCT Braille characters. The results show that most participants can discriminate them significantly faster with the finger cover than without it. From this study, it is found that the TRUCT Brailles' discriminability is influenced by the forefingers' slipperiness and it becomes easy to discriminate them with wearing finger cover.

Tactile ground surface indicators installed on side-walks help visually impaired people walk safely. The Visually impaired distinguish the indicators by stepping into its convexities and following them. However, these indicators sometimes cause the. nonvisually impaired to stumble. This study examines the effects of these indicators by comparing. the kinematic and kinetic variables of walking on paths with and without indicators. The results suggest that walking on the indicators causes extra movements of the lower extremities such as increased minimum toe heights during the midswing phase, increased peak hip flex moments, and increased peak hip heights. This study also suggests that a functional leg length discrepancy while walking on the indicators is one of the reasons for the extra movements of the lower extremities. Therefore, we designed a new recessed tactile surface to offset the differences of surface depth while walking on the path containing indicators, and found that the newly designed recessed tactile surface was effective in reducing the extra movements while walking on the path in which indicators were installed. These indicators may help both the visually impaired and elderly people with normal vision to walk safely.

Transparent-Resinous-Ultraviolet-Curing-Type Braille (TRUCT Braille) signs printed over printed characters do not disturb sighted readers, thus these signs have spread rapidly. However, it is pointed out that sight disabled readers are hard to read TRUCT Braille because patterns of dots that consist of Braille (such as dot-height and distance-between〜dots) are different from each printing marker. In this study, for the purpose of defining the readability of TRUCT Braille, we product the various patterns of TRUCT Braille and examine the influence of the dot-height and the distance-between-do...

Braille is one of the most popular visual substitution techniques for the blind to get information. Recently it is becoming a problem that many blind people cannot distinguish Braille. This problem is caused by the small size of the dots therefore, it is difficult especially for beginners to read them. The characteristics of embossed dots that consist of Braille are different from each printer, and it has been known that those characteristics affect the legibility. In this study, for the purpose of defining various patterns of Braille on a sensory level, we examine three factors; the influence of the cross section shapes, height of the dots, and the distance between dots. The participants of this experiment are beginning Braille readers with normal vision. They were given discrimination tasks of Braille-like patterns defined by the combination of three factors mentioned previously. The results show that the effects of the height of the dots and the distance between the dots were different among the shape of cross section, so distinguishability is influenced by interaction of each other, providing helpful data for legible Braille pattern.

The purpose of this study was to compare the effect between cyclists and noncyclists of pedal rates on ankle, knee, and hip joint torque during pedaling exercises.Six male cyclists (CY) and seven male noncyclists (NC) pedaled at 40, 60, 90 and 120 rpm with a power output of 200W.The lower limb was modeled as three rigid segment links constrained to plane motion.Based on the Newton-Euler method, the equation for each segment was constructed and solved on a computer using pedal force, pedal, crank, and lower limb position data to calculate torque at the ankle, knee, and hip joints.The average planter flexor torque decreased with increasing pedal rates in both groups.The average knee extensor torque for CY decreased up to 90 rpm, and then leveled off at 120 rpm.These results were similar to NC.The average knee flexor torque in both groups remained steady over all pedal rates.The average hip extensor torque for CY decreased significantly up to 90 rpm where it showed the lowest value, but increased at 120 rpm.For NC, the average hip extensor torque did not decrease at 90 rpm compared with 60 rpm, and was significantly higher than CY at 120 rpm(CY:28.1±9.0Nm, NC:38.6±6.7Nm, p<0.05).The average hip flexsor torque for NC at 120 rpm increased significanly from 90 rpm, and was significantly higher than CY(CY:11.6±2.9Nm, NC:22.6±11.8Nm, p<0.05).These results suggest that it would be better for cyclists to select a pedal rate of between 90 to 110 rpm to minimize joint torque, and, as a result, reduce peripheral muscle fatigue.