• Journal of the Korea Society of Computer and Information
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• v.23 no.7
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• pp.49-56
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• 2018

Virtual object weight perception is an important topic, as it heightens the believability of object manipulation in immersive virtual environments. Although weight perception can be achieved using haptic interfaces, their technical complexity makes them difficult to apply in immersive virtual environments. In this study, we present a visual pseudo-haptic feedback system that simulates and depicts the weights of virtual objects, the effect of which is weight perception. The proposed method recognizes grasping and manipulating hand motions using computer vision-based tracking methods, visualizing a Force Arrow to indicate the current lifting forces and its difference from the standard lifting force. With the proposed Force Arrow method, a user can more accurately perceive the logical and unidirectional weight and therefore control the force used to lift a virtual object. In this paper, we investigate the potential of the proposed method in discriminating between different weights of virtual objects.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.8 no.3
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• pp.151-160
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• 2014

In this study, the effect of the automotive haptic-seat technology which can transmit the driving information by the vibro-stimulus from the seat was investigated to overcome previous system's limitation relied on the visual and audial method and to help handicap driving. A prototype haptic seat cover with 30 coin-type motors and driver module were developed for this sake. In an experiment of seat vibration stimulation being performed under virtual driving situation by targeting the elderly aged over 65 years old, average score of test subjects for total vibration recognition was 3.5/4 points and recognition rate of 87.5% was represented. In addition, a result that all the test subjects totally recognized overspeed warning signal of 4 times was represented. As a result of statistical analysis for vibration recognition score by each group depending on TMT score, a significant difference was not found and a result that tactile function of which vibration is recognized even by the aged whose visual, perceptional function is declined showed an equal ability was obtained.. In this study it was shown that the seat vibration stimulus could be used to transfer the old drivers' information while driving.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.8 no.1
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• pp.75-78
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• 2015

Electric shock due to the increased use of power, equipment accidents, electrical accidents, such as electric fire and also continues to grow. To prevent electric shock accidents, an experience education is more effective than indoctrination education. But an electric shock experience education system required a proper physical stimulation on human body to experience electric shock. In this study, we conducted a study to take advantage of the realistic haptic interface using a low-frequency type experiential learning and prevention education. Results of this study could be applied to an electric shock experience education system.

• Proceedings of the Korean Society of Computer Information Conference
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• 2023.07a
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• pp.553-554
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• 2023

본 연구에서는 손가락의 움직임을 입력받는 햅틱 컨트롤러를 이용하여 물체를 잡거나 놓는 손의 포즈를 생성하여 가상의 물체를 제어할 수 있는 방법을 제안한다. 다섯 개의 손가락을 움직일 수 있는 경우의 수는 무수히 많아서 이를 위한 모든 모션을 캡쳐하는 것은 매우 힘든 작업이고, 캡쳐한 모든 모션을 수동으로 연결시키는 것도 어려운 일이다. 제안 방법은 햅틱 컨트롤러에서 입력된 다섯 개의 신호를 인공 신경망을 사용하여 손가락의 포즈로 변경해 준다. 이를 위해 입력 신호와 매칭되는 손의 포즈를 이용하여 인공 신경망을 훈련시킨 후, 그 결과를 이용하여 사용자의 입력에 대응하는 손의 포즈를 생성한다. 결과 포즈의 사실성을 높이기 위해 모션 캡쳐 장비로부터 훈련용 데이터를 생성하였다. 본 논문의 방법은 햅틱 컨트롤러에서 동일한 입력을 받더라도 물체의 모양에 대응하는 손의 모션을 생성하는 결과를 보여준다.

• 한국HCI학회:학술대회논문집
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• 2009.02a
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• pp.122-128
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• 2009

In this paper, we present a design and an evaluation of a hand-held ball based haptic interface, named "TouchBall." Using a trackball mechanism, the device provides flexibility in terms of directional degrees of freedom. It also has an advantage of a direct transfer of force feedback through frictional touch (with high sensitivity), thus requiring only relatively small amount of inertia. This leads to a compact hand-held design appropriate for mobile and 3D interactive applications. The device is evaluated for the detection thresholds for directions of the force feedback and the perceived amount of directional force. The refined directionality information should combine with other modalities with less sensory conflict, enriching the user experience for a given application.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.1
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• pp.18-25
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• 2003

A haptic hand controller (HHC) operated by the user’s hand can receive information on position and orientation of the hand and display force and moment generated in the virtual environment to the hand. In this paper, a 3-DOF hand controller is first presented, in which all the actuators are mounted on the fixed base by combining a 5-bar linkage and a gimbal mechanism. The 6-DOF HHC is then designed by connecting these two 3-DOF devices through a handle which consists of a screw and nut. Analysis using performance index is carried out to determine the dimensions of the device. The HHC control system consists of the high-level controller for kinematic and static analysis and the low-level controller for position sensing and motor control. The HHC used as a user interface to control the mobile robot in the virtual environment is given as a simple application.

• The Journal of Korea Robotics Society
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• v.7 no.1
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• pp.20-28
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• 2012

In spite of the difficulties and uncertain characteristic of cable driven method, surgical robot instrument has adopted it as driving mechanism for various reasons. To overcome the problem of cable system, previous research applied SMCSPO (sliding mode control with sliding perturbation observer) algorithm as robust controller to control the instrument and found that the value of SPO (sliding perturbation observer) followed force disturbance, reaction force loaded on the tip very similarly. Thus, this paper confirms that the perturbation observer is sufficient estimator which finds out the mount of loaded force on the surgical robot instrument. To prove the proposition, simulation using the similar model with an actual instrument and experimental evaluation are performed. The results show that it is possible to substitute SPO for sensors to measure the reaction force. This estimated reaction force will be used to realize haptic function by sending the reaction force to a master device for a surgeon. The results will contribute to create surgical benefit such as shortening the practice time of a surgeon and giving haptic information to surgeon by using it as haptic signal to protect an organ by making force boundary.

• Journal of Institute of Control, Robotics and Systems
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• v.20 no.8
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• pp.801-806
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• 2014

LAS (Laparoscopy Assisted Surgery) has been substituted alternatively for traditional open surgery. However, when using a commercialized robot assisted laparoscopic such as Da Vinci, surgeons have encountered some problems due to having to depend only on information by visual feedback. To solve this problem, a haptic function is required. In order to realize the haptic teleoperation system, a force feedback and bilateral control system are needed. Previous research showed that the perturbation value estimated by a SPO (Sliding Perturbation Observer) followed a reaction force that loaded on the surgical robot instrument. Thus, in this paper, the force feedback problem of surgical robots is solved through the reaction force estimation method. This paper then introduces the possibility of the haptic function realization of a laparoscopic surgery robot using a bilateral control system. For bilateral control, the master uses an impedance control and the slave uses a SMC (Sliding Mode Control). The experiment results show that a torque and force sensorless teleoperation system can be implemented using a bilateral control structure.

• Tribology and Lubricants
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• v.26 no.3
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• pp.184-189
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• 2010

In this paper, tactile response characteristics in medical haptic interface are investigated to characterize the feeling of contact between the finger skin and the organic tissue when a finger is dragged over tissue. In order to represent the tactile feeling, a prototype tactile display incorporating Magneto-Rheological (MR) fluid has been developed. Tactile display devices simulate the finger's skin to feel the sensations of contact such as compliance, curvature and friction. Thus, the tactile display provides the surface information of organic tissue to the surgeon using different actuating mechanisms ranging from the conventional mechanical motor to the smart material actuators. In order to investigate the compliance feeling of human finger's touch, vertical force responses of the tactile display under the various magnetic fields have been assessed. Also, frictional resistive force responses of the tactile display are investigated to simulate the action of finger's dragging. From the results, different tactile feelings are observed as the applied magnetic field is varied and arrayed magnetic poles combinations. This research gives a smart technology of tactile displaying.

• Proceedings of the KIPE Conference
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• 2001.07a
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• pp.9-13
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• 2001

This paper proposes the electric stimulus tactile apparatus system(TESTAS) loaded on the hap-tic interface using ultrasonic motors(USMs). To touch the virtual object like wall in graphic, the 6 DOF haptic interface provides force feedback to users as if it is real. But the case of sharp virtual object like a puncture, it could not provided the sense of pain, but only the reaction-force. After the TESTAS had been loaded on this haptic interface. it could Provide not only the force but also the pain to users. To estimate the capability of TESTAS, we did experiments of three cases, one was very sharp, another was dull, the other is continuative contact.