Transparent Transducer and Creative Research Center

Daejeon, South Korea

Transparent Transducer and Creative Research Center

Daejeon, South Korea

Time filter

Source Type

Ryu S.,KAIST | Koo J.-H.,Miami University Ohio | Yang T.-H.,Center for Mass and Related Quantities | Pyo D.,KAIST | And 2 more authors.
Journal of Intelligent Material Systems and Structures | Year: 2016

This study presents a miniature haptic actuator (10 mm (L) × 10 mm (W) × 6.5 mm (H)) based on magnetorheological fluids, which is designed to provide realistic touch sensations to users. Its primary goals are to evaluate mechanical or actuation performances of the prototype magnetorheological actuator and to assess its effectiveness in conveying haptic sensations to users by conducting the psychophysical experiments. The mechanical performance study evaluated the prototype's output forces from haptic perspectives using a dynamic test frame. The psychophysical experiments studied human subjects' perceptions on haptic sensations produced by the prototype. The mechanical test results show that the magnetorheological actuator is capable of generating a wide range of frequency-dependent output forces (from 1.5 N to nearly 9 N). The psychophysical experiments show that the actuator offers various kinesthetic and vibrotactile sensations to human operators. Overall, the results suggest a feasibility of using the magnetorheological haptic actuator in real-world applications, such as a haptic keypad and functional buttons in small consumer electronics and hand-held devices. © The Author(s) 2015.


Ryu S.,KAIST | Koo J.-H.,Miami University Ohio | Yang T.-H.,Center for Mass and Related Quantities | Pyo D.,KAIST | And 2 more authors.
ASME 2013 Conference on Smart Materials, Adaptive Structures and Intelligent Systems, SMASIS 2013 | Year: 2013

This study presents a novel design of a miniature haptic actuator based on Magneto-Rheological (MR) fluids for mobile applications, and it evaluates the performance of a haptic actuator using a simulation model. The primary design goal for a haptic actuator for mobile applications is to miniaturize its size while generating realistic haptic sensations. To this end, this study proposes to design the MR actuator's piston head (or plunger) in cone-shape and activate multiple modes of MR fluids (direct shear, flow and squeeze modes). Using a simulation model developed by integrating magnetic and force equations, the performance of a haptic actuator was evaluated in terms of the force (resistive force) produced by the actuator. The results show that a small actuator model, dimension of 10 mm (L) × 10 mm (W) × 6.5 mm (H), produced a maximum resistive force of about 5 N at 0.3 Watts, which is sufficient to provide force feedback to users. Copyright © 2013 by ASME.


Ryu S.,KAIST | Koo J.-H.,Miami University Ohio | Yang T.-H.,Center for Mass and Related Quantities | Pyo D.,KAIST | And 2 more authors.
ASME 2014 Conference on Smart Materials, Adaptive Structures and Intelligent Systems, SMASIS 2014 | Year: 2014

This paper presents design and testing of a haptic keypad system using an array of haptic actuators. The research goals are to construct a prototype haptic keypad system using haptic actuators and to evaluate the performance of the prototype keypad for haptic rendering. To this end, an MR haptic actuator was designed and fabricated such that it can convey realistic force feedback to users. To demonstrate haptic applications of the MR actuator, a haptic keypad system was constructed, which consists of following components: (1) 3 × 3 array of haptic actuators, (2) 3 × 3 array of force sensing resistors (FSR), (3) a controller including a micro-processor, a current amplifier and a wireless communication module, (4) a graphic display unit with PC. After constructing a prototype keypad system, a haptic rendering technology was employed to interface the hardware keypad system with test software (virtual environment). The prototype system enabled human operators to interact with the target contents in a virtual environment more intuitively. The evaluation results show a feasibility of applications of MR fluids-based haptic actuators in real-world mobile applications. © 2014 by ASME.


Ryu S.,KAIST | Koo J.-H.,Miami University Ohio | Yang T.-H.,Center for Mass and Related Quantities | Pyo D.,KAIST | And 2 more authors.
Journal of Intelligent Material Systems and Structures | Year: 2015

This article presents a novel design of a miniature haptic actuator based on magnetorheological fluids for mobile applications with the aim of providing various haptic sensations to users in mobile devices. The primary design goal for a haptic actuator for mobile applications is to miniaturize its size while achieving large forces and low power consumption. To this end, this study proposes to design the actuator's piston head (or plunger) in cone shape and activate multiple modes of magnetorheological fluids. A prototype actuator was designed and fabricated based on a simulation model. Using a dynamic test frame, the performance of the prototype actuator was evaluated in terms of the force (resistive force) produced by the prototype. The results show that the small actuator (10 mm × 10 mm × 6.5 mm) produced a maximum resistive force of about 5 N and the force rate of nearly 80% at 0.3 W. This change in resistive force or the force rate is sufficient to provide several steps of force variation that is explicitly perceivable for operators, depending on the input power. The results demonstrate a feasibility of using the proposed actuator's applications in mobile devices, conveying realistic haptic sensations to users. © SAGE Publications.


Kim Y.,Transparent Transducer and Creative Research Center | Park S.,Transparent Transducer and Creative Research Center | Kyung K.-U.,Transparent Transducer and Creative Research Center
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2012

This paper describes a transparent haptic feedback interface composed of a transparent haptic actuator and a transparent pressure sensor. The transparency values of the haptic actuator and the pressure sensor are 0.81 and 0.95 respectively. Since the pressure sensor is like a thin film, the haptic actuator is overlaid with the sensor film. Total thickness of the integrated haptic interface is 860μm. © 2012 Springer-Verlag.


Nam S.,Transparent Transducer and Creative Research Center | Park S.,Transparent Transducer and Creative Research Center | Yun S.,Transparent Transducer and Creative Research Center | Park B.J.,Transparent Transducer and Creative Research Center | And 3 more authors.
Lecture Notes in Electrical Engineering | Year: 2015

This demonstration shows a highly flexible, transparent, and thin tactile sensor. The sensor detects touch forces at single or multiple points with fast response and high bendability in response to dynamic input force (0-3 N) without any electronic components on sensing areas. The sensor is also capable of sensing pressure on curvilinear soft surface such as human skin without significant performance degradation. The force sensor has potentials to be used in a number of applications for measuring dynamic contact forces on various surfaces. © Springer Japan 2015.


Park B.J.,Transparent Transducer and Creative Research Center | Park S.,Transparent Transducer and Creative Research Center | Yun S.,Transparent Transducer and Creative Research Center | Nam S.,Transparent Transducer and Creative Research Center | Kyung K.-U.,Transparent Transducer and Creative Research Center
Sensors and Actuators, A: Physical | Year: 2015

Abstract We demonstrate a transparent visuo-haptic input device. The device consists of optical waveguide based thin film display, sensor, and surface actuator. Highly transparent flexible display and sensor with high are fabricated by using Bisphenol A ethoxylate diacrylate (na = 1.5647 @ 632 nm) and Tetra diacrylate (na = 1.5031 @ 632 nm) for core and clad, respectively. The display and sensor are thin (thickness: < 70 μm), highly transparent (optical transmittance: as high as 90%) and designed as a form of 3 × 9 matrix. Surface actuator is fabricated as a combination of ITO electrode coated two rectangular glass plates, which are sandwiched with a constant air gap. The surface actuator produces electrically induced dynamic deformation responses of displacement as high as 157 μm and output force as large as 60 mN under a sinusoidal input voltage signal of 2 kV at 140 Hz. The visuo-haptic display integrating the three functional components is capable of realizing sufficient and human perceivable vibro-tactile response on a touch interface for QWERTY keypad. © 2015 Elsevier B.V.

Loading Transparent Transducer and Creative Research Center collaborators
Loading Transparent Transducer and Creative Research Center collaborators