캠기반 요골동맥 펄스 시뮬레이터 개발

양태헌 韓國交通大學校 2022 한국교통대학교 논문집 Vol.57 No.-

The goal of this study is to develop a small and economical pulsation simulator that can generate various radial artery pressure waveforms. For this, many pulse waveforms were collected from the subjects using a robotic pulse pressure measurement system, and standard pulse waveforms of the subjects were defined from the data collected using a mathematical model. This standard pulse waveform was used to design and fabricate the cam profile. Using the fabricated cam, a pneumatic pulse waveform generating system based on DC motor and cam-follower mechanism was developed. The developed pulsation simulator was developed to include a mechanism to control the magnitude of the pulse pressure and heart rate, and a real-time pulse display. To verify the performance of the developed pulsation simulator, a series of tests were performed on the waveform generated by the pulsation simulator while varying the pressure level and heart rate using a robotic pulse pressure measurement system. As a result of the radial augmentation index (AI) and phase analysis between the human standard pulse waveform and the waveform generated by the simulator, it was confirmed that the error ratio was small enough that the proposed simulator can generate a human pulse waveform.

통합형 햅틱 디스플레이 개발

양태헌 한국교통대학교 2020 한국교통대학교 논문집 Vol.55 No.-

This paper presents a new miniature integrated haptic device consisting of a cutaneous, a thermal and a kinaesthetic module. To convey realistic tactile sensation in compact size, the cutaneous module is designed to contain a 3x3 miniature pin-array tactile device and amplitude-modulated vibration generator. The pin-array mimics from small-scale shape to rough surface, and the amplitude-modulated vibration replicates continuous texture feeling of the virtual object. The vibration generator is fabricated using a stack multilayer piezo actuator and a flexure structure. To further enhance the sense of reality, the thermal module including a peltier element and a cooling jacket is integrated to the cutaneous module. In addition to tactile information, the kinesthetic information is equally important in perceiving objects. Thus, two kinaesthetic actuators operated by MR fluids are inserted to the whole device by supporting the cutaneous module and the thermal module. Therefore, when users explore over virtual environments, they can simultaneously feel a cutaneous, a thermal and a kinaesthetic sensation by using the developed compact integrated haptic device.

요골동맥 혈압파형 재현을 위한 의료로봇 시뮬레이터 개발

양태헌 한국교통대학교 2019 한국교통대학교 논문집 Vol.54 No.-

Radial pulsation waveforms in human is a surrogate maker of estimating the central versus arterial pressure waveforms that are clinically essential for predicting cardiovascular disease. Due to technical limitations, the ability to transfer between central and radial pressures has not been reliably proven. Therefore, to verify the mathematical function between the central pressure and the radial pressure, we developed a prototype radial pulsation simulator that mimics the real human cardiovascular system. The proposed simulator consists of a ventricle, an atrium, arteries and precision sensing equipment. When viscous fluid is injected into the ventricles, the resulting forward wave encounters a unique fluid at the branch of the artery. The reflected wave from the branch propagated backwards, increasing the pressure. The resulting central pressure waveform with extended shoulders was delivered to the radial and ulnar arteries. As a result of the experiments, the developed radial pulsation simulator can now produce radial pressure waveforms like humans. The results suggest that the developed simulator is likely to generate several pressure waveforms representing cardiovascular disease, and that the proposed simulator can be applied to verify the generalized transfer function between the central and radial pressure waveforms.

워킹네비게이션을 위한 소형 촉감모듈의 디자인

양태헌,진경복,박원형,김상연 한국지식정보기술학회 2016 한국지식정보기술학회 논문지 Vol.11 No.3

According to demands for tactile feedback in mobile devices, vibration motors have been used to convey tactile sensation, because the vibration motor is small and consumes low power. However, the vibration motor is not sufficient to generate fruitful tactile sensation. In this paper, we propose a new miniature tactile actuator using elastic restoring and electromagnetic force for providing minute and various tactile sensation in the mobile devices. The proposed tactile actuator consists of a solenoid, a permanent magnet, and an elastic spring. There is an interaction force between the solenoid and the permanent magnet in the proposed actuator. This interaction force is combined with elastic restoring force from the elastic spring to maximize the tactile feedback. Since two forces contribute to the actuation of the proposed motor, the presented tactile actuator can create strong enough force to stimulate human skin in small-sized devices and furthermore it consumes low power. Therefore, tactile actuator satisfies the specification to create haptic sensation (contactors' stroke, output force and working frequency). By connecting the nine actuators to the multilayered elastic springs, we can easily design a miniature tactile module. We measure the output force and the amplitude of the proposed module according to frequency variation in order to investigate that the proposed module create enough force to stimulate human mechanoreceptors over a wide frequency range. Through the experiments, the proposed module has good potential in walking navigation systems.

Electrostatic Resonance 초박형 햅틱 액추에이터 어레이 개발

양태헌 한국교통대학교 2021 한국교통대학교 논문집 Vol.56 No.-

Vibrotactile feedback is a key feature of modern touch displays, greatly improving the user's operability and immersion when interacting with the on-screen interface. In this study, we intend to propose a vibrotactile actuator suitable for mounting on the back of a medium or large display because it can generate strong vibration output by applying an electrostatic force-based mechanism and can be manufactured in a thin flat panel type. The proposed actuator has been developed in a structure that can amplify the vibration force by alternating the electrically grounded mass with electrostatic force by the upper and lower electrodes spaced apart from the radial plate spring. As a result of the performance evaluation, the developed bar-type module with two built-in actuators showed excellent vibration output of up to 14 g at 135 Hz, confirming the possibility of providing haptic feedback in medium and large-sized touch displays.

Development of a novel variable conductance vacuum valve

양태헌,송한욱,우삼용 한국진공학회 2017 한국진공학회 학술발표회초록집 Vol.2017 No.2

로봇용 대화면 햅틱 디스플레이 기술 개발

양태헌 한국교통대학교 2018 한국교통대학교 논문집 Vol.53 No.-

Recently, the rapid development of smart device technology has been combined with the smart car and the robotic kiosk area, and the button panel of the automobile has been replaced with the large-area touch LCD panel. In order to prevent the driver from concentrating on the operation when touching with the click and drag, a technique for providing haptic feedback by vibration is required. In this paper, we introduce electrostatic resonant actuator, which is thinly mounted on the back of a large-area LCD and developed to transmit strong vibration feedback to the touching surface. The developed actuator is designed to generate beat oscillations using electrical interference between two isolated electrodes to provide vibration feedback over a wide frequency range. As a result of the performance evaluation, it was confirmed that it can generate a high vibration power of 5 g or more in a state including about 250 g of the base housing. This means that the developed haptic actuator can provide sufficiently strong vibration feedback on the touching surface even when mounted on the back of a large area LCD.

심혈관계 시뮬레이터의 개발 동향

양태헌,신상훈 대한전자공학회 2016 전자공학회지 Vol.43 No.12

요골동맥 압력파형 생성을 위한 캠기반 소형 맥동 시뮬레이터

양태헌(Tae-Heon Yang),조광현(Gwanghyun Jo),구정회(Jeong-Hoi Koo),우삼용(Sam-Yong Woo),김재욱(Jaeuk U. Kim),김영민(Young-Min Kim) 대한전기학회 2018 정보 및 제어 심포지엄 논문집 Vol.2018 No.10

Development and Evaluation of an Impact Vibration Actuator using an Unstable Mass for Mobile Devices

김상연,양태헌,표동범,권동수 제어·로봇·시스템학회 2016 International Journal of Control, Automation, and Vol.14 No.3

The most important thing in haptic interaction with mobile devices is to create vibrotactile sensationwith wide frequency range. However, it is not easy to generate vibrotactile signal with wide frequency range withconventional vibrotactile actuators. Therefore, this paper presents a miniature impact type actuator, which haswide enough frequency range to selectively stimulate mechanoreceptors, consisting of a mass, an elastic spring, ahousing, and a solenoid. To create strong impact force in wide frequency range in real-time, we adopt an unstablestructure. Due to the impact with fast rising and falling time in the proposed vibration actuator, strong impactvibration can be created over wide frequency range. We simulate the magnetic flux line of the proposed actuatorand magnetic force applied to the mass using an FEM simulation tool. We carry out an experiment in order toinvestigate the response time of the proposed actuator. Another experiment is conducted to show that the proposedactuator can create sufficient output force to stimulate human skin over a wide frequency bandwidth and can conveya variety of vibrotactile sensations to users.