• Elastomers and Composites
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• v.58 no.4
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• pp.173-178
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• 2023

Recently, there has been a significant focus on the development of flexible and stretchable sensors, driven by advancements in electronic devices and the robotics industry. Among these sensors, tactile sensors stand out as the most actively researched, playing a crucial role in facilitating interaction between humans and electronic devices, particularly in robotics and medical applications. This study specifically involves the manufacturing of a capacitive tactile sensor using a relatively straightforward process and sensor structure. Natural rubber and Nitrile butadiene rubber, commonly employed in the rubber industry, were utilized. The dielectric material in the manufactured tactile sensor possesses a porous structure. Notably, the resulting tactile sensor demonstrated excellent sensitivity, approximately 1%/kPa, and exhibited the capability to detect pressures up to 212 kPa.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.1029-1032
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• 2002

This paper describes a design of a tactile sensor, which can measure three components force and temperature due to thermal conductive. The bio-mimetic tactile sensor, alternative to human's finger, is comprised of four micro force sensors and four thermal sensors, and its size being 10mm$\times$10mm. Each micro force sensor has a square membrane, and its force range is 0.1N - 5N in the three-axis directions. On the other hand, the thermal sensor for temperature measurement has a heater and four temperature sensor elements. The thermal sensor is designed to keep the temperature. $36.5^{\circ}C$, constant, like human skin, and measure the temperature $0^{\circ}C$ to $50^{\circ}C$. The MEMS technology is applied to fabricate the sensing element of the tactile sensor.

• Journal of Korea Multimedia Society
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• v.7 no.6
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• pp.767-780
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• 2004

Interaction requires dynamic relationship between objects. In ubiquitous computing environment, interaction between human and the environment is implied. Tactile interaction has so far been less addressed, while tactile sensation should be an important topic in the field of multimedia study. This paper describes development of a novel PVDF (Polyvinylidene Fluoride) dynamic tactile sensor and associated experiments. PVDF dynamic tactile sensors detect touch events applied to the sensor skin by low frequency components of the signal. Rubber skin-covered sensing material was mounted on the bones. Robust performance with low noise was figured out in our robotic experiment. Whereas most conventional sensors are interested in measurement, our dynamic tactile sensor is sensitive to change of state, which could be a key for economic understanding of happenings in the dynamic world. We note that dynamic sensing uses motion as a part of sensing modality We suggest that dynamic sensing be understood in technological terms in the perspective of interactive media and ubiquitous computing.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.1802-1807
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• 2005

Tangible interface can be understood as a newly defined concept, which can provide an effective and seamless interaction between the human as a subjective existence and the cyberspace as an objective existence. Tactile sensation is essential for many exploration and manipulation tasks in the tangible space. In this paper, we suggest the design of an integrated tactile sensor-display system that provides both of sensing and feedback with kinesthetic force, pressure distribution, vibration and slip/stretch. A new tactile sensor with PDVF strips and display system with bimorph actuators has been developed and integrated by developed signal processing algorithm. In the scenario of haptic navigation in the tangible space, tactile feedback system is successfully experimented.

• Journal of Electrical Engineering and Technology
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• v.12 no.1
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• pp.310-316
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• 2017

The robot proximity and tactile sensors can be categorized into two groups: grip sensors and safety sensors. They have different performance requirements. The safety sensor should have long proximity range and fast response in order to secure enough response time before colliding with ambient objects. As for the tactile sensing function, the safety sensor need to be fast and compliant to mitigate the impact from a collision. In order to meet these requirements, we proposed and demonstrated a compliant integrated safety sensor suitable to human-friendly robots. An ultrasonic proximity sensor and a piezoelectric tactile sensor made of PVDF films have been integrated in a compliant PDMS structure. The implemented sensor demonstrated the maximum proximity range of 35 cm. The directional tolerance for 30 cm detection range was about ${\pm}15^{\circ}$ from the normal axis. The integrated PVDF tactile sensor was able to detect various impacts of up to 20 N in a controlled experimental setup.

• Journal of the Korean Society of Industry Convergence
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• v.20 no.3
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• pp.233-243
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• 2017

This paper proposes a structure of direct-printed flexible tactile-sensor. These flexible tactile sensors are based on pressure-sensing materials that allow pressure to be measured according to resistance change that in turn results from changes in material size because of compressive force. The sensing material consists of a mixture of multi walled carbon nanotubes (MWCNTs) and TangoPlus, which gives it flexibility and elasticity. The tactile sensors used in this study were designed in the form of array structures composed of many lines so that single pressure points can be measured. To evaluate the performance of the flexible tactile sensor, we used specially designed signal-processing electronics and tactile sensors to experimentally verify the sensors' linearity. To test object grasp, tactile sensors were attached to the surface of the fingers of grippers with three degrees of freedom to measure the pressure changes that occur during object grasp. The results of these experiments indicate that the flexible tactile sensor-based robotic gripper can grasp objects and hold them in a stable manner.

• Journal of Institute of Control, Robotics and Systems
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• v.10 no.1
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• pp.60-65
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• 2004

A flexible tactile sensor away with 8 H 8 tactile elements is designed and fabricated. The material of the sensor is PVDF(polyvinylidene fluoride) film and flexible circuitry is used in the fabrication fur the flexibility of the sensor The experimental results on static and dynamic properties of the sensor are obtained and examined. The signals of a contact pressure to the sensor are sensed and processed in the DSP system in which the signals are digitalized and filtered. The processed signals of the sensor outputs are visualized in a personal computer for illustrating the shape and force distribution of a contact object. The reasonable performance for the detection of contact state is verified through sensing examples.

• Journal of the Korean Society for Precision Engineering
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• v.31 no.2
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• pp.157-164
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• 2014

In this paper, we design a gripping force control system using tactile sensor to prevent slip when gripper tries to grasp and lift an object. We use a flexible tactile sensor for measuring uniplanar pressure on gripper's finger and develop an algorithm to detect the onset of slip using the sensor output. We also use a flexible pressure sensor to measure the normal force. In addition, various signal processing techniques are used to reduce noise included in the sensor output. A 3-finger gripper is used to grasp and lift up a cylindrical object. The tactile sensor is attached on one of fingers, and sends output signals to detect slip. Whenever the sensor signal is similar to the slip pattern, gripper force is increased. In conclusion, this research shows that slip can be detected using the tactile sensor and we can control gripping force to eliminate slip between gripper and object.

• Vacuum Magazine
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• v.4 no.3
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• pp.6-11
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• 2017

The tactile sensor of the future robot is becoming a necessity as a sensory organ which can communicate with the person most directly. Recently, the Nature-inspired technology has provided a new direction for the development of these tactile sensors. Here, we review three different nature-inspired tactile sensory system; high sensitivity pressure sensor inspired by beetle wings, highly sensitive strain sensor inspired by the spider's sensory organs, Tactile sensor inspired by human fingertip. These nature-inspired tactile sensors are expected to provide a breakthrough that not only can sensitively measure the pressure, but also delicately recognize the softness and texture of the material just like human.

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.97.6-97
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• 2002

In this paper, we present an arrayed flexible tactile sensor, which can detect contact normal forces as well as positions. The tactile sensor is developed using Polyvinylidene Fluoride (PVDF) that is known as piezoelectric polymer, and the surface electrode is fabricated using silk-screening technique with silver. We develop a charge amplifier in order to amplify the small signal from the sensor, and a fast signal processing unit by using a DSP chip. The developed tactile sensor is physically flexible and it can be deformed three-dimensionally to any shape so that it can be placed on anywhere on the curved surface. In the future, the developed sensor is applied to a dexterous robotic hand...$\textbullet$ Tactile sensing, PVDF, Robot hand