• Journal of Institute of Control, Robotics and Systems
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• v.9 no.8
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• pp.592-599
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• 2003

As one of the Principal modalities of human sensation, tactile feel is prerequisite for building wide variety of applications such as telemanipulation, virtual reality and medical engineering. A dynamic Braille display device based on a polymer actuator is presented. The actuator, often called artificial muscle actuator has advantageous features over the existing methods in terms of intrinsic softness, ease of fabrication, cost-effectiveness and miniaturization. The principles of actuation with dielectric elastomer is introduced, and necessary considerations on the design of a tactile display device are discussed. The design of the device is described in detail including the fabrication process and driving electronics. Also, preliminary results of experiments are given to evaluate its performance.

• Journal of Sensor Science and Technology
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• v.18 no.3
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• pp.210-216
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• 2009

In this paper the tactile sensor system based on the bending loss of optical fiber sensor is presented. The sensor array was designed with fabric structure. The optical measuring system was composed of LED for light source and CCD camera for the signal light detector. Performance of this tactile sensor system was evaluated in various environments and compared with Harmon's design criteria. The result shows that load range is 3 g$\sim$100 g, resolution is 1.5 g, hysteresis error is 1.5%. The response linearity is good and flexibility of sensor array is excellent.

• Journal of Sensor Science and Technology
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• v.15 no.4
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• pp.251-256
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• 2006

This paper describes the flexible force sensor using fiber Bragg grating (FBG) and silicone rubber for the tactile sensation to detect the distributed normal force. The newly designed FBG flexible force has simple structure and can be easily multiplexed with simple wiring compared with the other electric mechanical sensors. We designed the flexible silicone rubber transducer and found the optimum embedding position of FBG in the transducer using the finite element analysis. This flexible force sensor has good performance and is immunity to the electromagnetic field compared with any other kinds of small force sensors for tactile sensation.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.61.4-61
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• 2001

This research is the development of a distributed flexible tactile sensor for service robots using PVDF (polyvinylidene fluoride) film for the detection of the contact state in real time. The tactile sensor which has 8$\times$8 taxels is fabricated using PVDF film and flexible circuitry. The proposed fabrication method is simple and easy to make the sensor in the laboratory without using any special equipment. Experimental results on static and dynamic properties are obtained. In order to investigate the properties of the sensor, the sensor output to the arbitrary forces and frequencies are measured using the shaker with the force sensor.

• The Korean Journal of Pain
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• v.9 no.2
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• pp.311-317
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• 1996

Background: Following peripheral nerve injury, rats will show a tactile allodynia and hyperalgesia. But the mechanism of allodynia is still obscure. Previous studies have shown this allodynia was reversed by intrathecal alpha-2 agonists and NMDA antagonists, but not by morphine. In formalin test, either the pretreatment of NMDA antagonist or morphine prevents the hyperalgesia. The present studies, using rats rendered allodynic by ligation of the left L5 and L6 nerves, aimed to investigate the effects of pretreatment of MK-801 and morphine on the development of tactile allodynia. Methods and Material: Male Sprague-Dawley rats (100~150g) were anesthetized with halothane, the left L5 and L6 spinal nerves were ligated tightly by 6-0 black silk. For sham operation muscle dissection was performed but the spinal nerve was not ligated. For pretreatment of drugs, MK-801 (NMDA antagonist; 0.3 mg/kg). CNQX (non-NMDA) antagonist; 0.3 mg/kg), morphine (1 mg/kg) or saline (placebo) was administered subcutaneously 30 minutes before operation. A second dose was administered subcutaneously 24 hours after operation and further doses were given daily for 2 days further. The volume of injection was 5 ml/kg. To assess the mechanical allodynia, paw withdrawal thresholds of ipsilateral limb were determined using 8 von Frey hairs. Results: Within 2 days saline, CNQX or morphine injected rats developed tactile allodynia (paw withdrawal threshold was about 2g), and persisted for over 2 weeks. Pretreatment of MK-801 delayed the development of tactile allodynia for 3 days comparing to that of saline injected rat. Conclusion: NMDA receptor in the central nerve system plays an important role in the development of tactile allodynia induced by peripheral nerve injury. But the mechanism may be different from hyperalgesia developed in formalin test.

• Journal of the HCI Society of Korea
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• v.1 no.2
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• pp.19-26
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• 2006

This paper presents a novel pneumatic tactile display that can deliver some useful information. The air-jet display forms 5 by 5 arrays and features air nozzles with an external diameter of 2.4mm and internal diameter of 1.5 mm. In comparison with other tactile displays such as vibrotactile, there is little concrete psychophysical data relating to pneumatic displays, a fact which hinders their adoption. This paper addresses this challenge, and presents brief psychophysical studies examining localization rate, the two point threshold, stimulus intensity and the temporal threshold of cues produced by pneumatic air jets. Two groups of subjects were used in these studies, subsequently termed groups A and B. Both were comprised of eight participants. In the case of localization study we obtained 58.13% and 85.9% of localization rates each for dense display and sparse display. Two-points threshold test showed the length of gap between two air-jet stimuli which subjects can detect. However, it was formidable to find out precise temporal resolution of PTI owing to the limitation of capability of the pneumatic valves. Lastly, the results of stimulus intensity study suggest that by varying the size of a pneumatically created tactile stimulus, we can effectively vary its perceived magnitude.

• Science of Emotion and Sensibility
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• v.20 no.4
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• pp.55-64
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• 2017

This study was performed to help the denim fabric planning which reflects the sensibility preference of university students. Objective characteristics, like color properties and mechanical properties, in 8 denim fabrics (5 cotton 100% fabrics and 3 cotton/polyurethane blended fabrics) were evaluated. And the color preference, subjective sensation and tactile preference of denim fabrics were investigated among the university students. The effect of color preference and tactile preference of denim fabrics on the purchase preference of denim slacks was also examined. Color preference of denim fabrics showed a significant difference according to the kind of denim fabrics. University students preferred purple blue denim fabrics that was measured low $-b^*$ value and low $C^*$ value among the color properties of denim fabrics. Among the mechanical properties of denim fabrics, surface property like MMD, MIU and SMD as well as shear property like 2HG5 were important elements affecting subjective sensation. While, tactile preferences showed a significant difference according to the fabrics. The tactile preferences of cotton/polyurethane blended denim fabrics was highly preferred, and that of heavy 100% cotton denim fabric was lowly preferred. And the subjective sensation affecting tactile preferences were in order of smoothness, softness, lightness. It is concluded that the color preference and tactile preference influenced upon the purchase preference of denim slacks, and color preference had a bigger effect upon the purchase preference.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.05a
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• pp.829-830
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• 2012

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.1314-1317
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• 1997

For realizing artificial skin sensing as a final goal, a mono-material pressure-conductive rubber sensor which is also sensitive for temperature is described. Firstly, discimination of the hardness and the thermal property of material using a proposed sensor is presented. Furthermore, a tactile sensor constints of four pressure-conductive rubber sensor to discriminate surface model which imitaties the surface roughness of material is proposed.

• Journal of international Conference on Electrical Machines and Systems
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• v.2 no.4
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• pp.436-440
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• 2013

An haptic tactile interface (HTI) is presented with its modeling. Its design is dedicated to perform friction coefficient measurement to characterize reachable feelings with that kind of interface. Friction measurements are presented and discussed.