Wanjoo Park

A universal remote control with haptic interface for customer electronic devices

We introduce a new universal remote control that gives easy-to-control interface for home devices such as TV, video/audio player, room lighting and temperature control. In order to use conventional remote controls, people need to understand complex instruction manuals and remember functions assigned to buttons. In addition, the button-based control does not provide an intuitive interface so the user presses a button several times to browse information and has difficulty in searching the right button among many buttons. Our universal remote control addresses these limitations by using a touch screen, a force-feedback dial knob, and two buttons instead of many buttons. We suggest an example scenario to interact with a conventional TV set, room lighting, and air conditioner using our universal remote control. The result of a user study to evaluate the usability of the device shows that the universal remote control is very efficient and intuitive interface to control customer electronics devices.

Design of haptic interface for brickout game

This paper introduces a haptic interface for brick games. Conventionally the game user uses mouse or keyboard to play the brick game. However, these input devices do not provide intuitive interface for the game and any tactile feedback to the user. We use a haptic dial to add tactile feedback to enhance game effects in addition to visual and sound effects. The user changes the position of the paddle by spinning the dial knob and feels various tactile feedbacks according to the game context. Tactile feedbacks include friction, jog dial, barrier, detent, and any combinations of these effects which are programmed based on the amount, frequency, and direction of torque along the rotational path. These effects are used as either penalties or useful tools. The proposed haptic dial interface makes the game more fun and gives a very intuitive interface to the game user.

EEG response varies with lesion location in patients with chronic stroke.

BackgroundBrain activation differs according to lesion location in functional magnetic resonance imaging (fMRI) studies, but lesion location-dependent electroencephalographic (EEG) alterations are unclear. Because of the increasing use of EEG-based brain-computer-interface rehabilitation, we examined lesion location-dependent EEG patterns in patients with stroke while they performed motor tasks.MethodsTwelve patients with chronic stroke were divided into three subgroups according to their lesion locations: supratentorial lesions that included M1 (SM1+), supratentorial lesions that excluded M1 (SM1-), and infratentorial (INF) lesions. Participants performed three motor tasks [active, passive, and motor imagery (MI)] with supination and grasping movements. The hemispheric asymmetric indexes, which were calculated with laterality coefficients (LCs), the temporal changes in the event-related desynchronization (ERD) patterns in the bilateral motor cortex, and the topographical distributions in the 28-channel EEG patterns around the supplementary motor area and bilateral motor cortex of the three participant subgroups were compared with those of the 12 age-matched healthy controls.ResultsThe SM1+ group exhibited negative LC values in the active and MI motor tasks, while the other patient subgroups exhibited positive LC values. Negative LC values indicate that the ERD/ERS intensity of the ipsilateral hemisphere is higher than the contralateral hemisphere, whereas positive LC values indicate that the ERD/ERS intensity of the contralateral hemisphere is higher than the ipsilateral hemisphere. The LC values of SM1+ and healthy controls differed significantly (rank-sum test, p < 0.05) in both the supination and grasping movements in the active task. The three patient subgroups differed distinctly from each other in the topography analysis.ConclusionsThe hemispheric asymmetry and topographic characteristics of the beta band power patterns in the patients with stroke differed according to the location of the lesion, which suggested that EEG analyses of neurorehabilitation should be implemented according to lesion location.

Assessment of Cognitive Engagement in Stroke Patients From Single-Trial EEG During Motor Rehabilitation

We propose a novel method for monitoring cognitive engagement in stroke patients during motor rehabilitation. Active engagement reflects implicit motivation and can enhance motor recovery. In this study, we used electroencephalography (EEG) to assess cognitive engagement in 11 chronic stroke patients while they executed active and passive motor tasks involving grasping and supination hand movements. We observed that the active motor task induced larger event-related desynchronization (ERD) than the passive task in the bilateral motor cortex and supplementary motor area (SMA). ERD differences between tasks were observed during both initial and post-movement periods (p <; 0.01). Additionally, differences in beta band activity were larger than differences in mu band activity (p <; 0.01). EEG data was used to help classify each trial as involving the active or passive motor task. Average classification accuracy was 80.7±0.1% for grasping movement and 82.8±0.1% for supination movement. Classification accuracy using a combination of movement and post-movement periods was higher than in other cases (p <; 0.05). Our results support using EEG to assess cognitive engagement in stroke patients during motor rehabilitation.

An universal remote controller with haptic interface for home devices

We introduce a new universal remote controller that gives easy-to-control interface for home devices such as TV, video/audio player, room lighting and temperature control. In order to use a conventional remote controller, one should study an instruction manual and remember function for each button. In addition, the remote controller does not provide an intuitive interface so the user has difficulty in searching the right button among a lot of small buttons. Our remote controller addresses these limitations by using a touch screen, a force-feedback dial knob, and a single button instead of many buttons. We suggest an example scenario to interact with a conventional TV set using our remote controller.

Haptic Mouse Interface Actuated by an Electromagnet

In this paper, we propose a hap tic feedback mouse that is actuated by an electromagnet. The hap tic mouse works like a normal optical mouse but attraction force is generated between the electromagnet and a ferromagnetic mouse pad. We introduce some examples using the hap tic mouse. For example, when the mouse cursor moves into the click able area, magnetic attraction generates strong friction, allowing the user to find the target easily. In another example, the system gives the user tactile feedback when the mouse cursor passes lines. This would be helpful to increase working efficiency for CAD work and could graphic designers who must perform abundant mouse control to select lines. If this system is integrated into computer games, it can provide the game user with various tactile experiences.

A rehabilitation device to improve the hand grasp function of stroke patients using a patient-driven approach

This paper proposes a robotic hand rehabilitation device for grasp training. The device is designed for stroke patients to train and recover their hand grasp function in order to undertake activities of daily living (ADL). The device consists of a control unit, two small actuators, an infrared (IR) sensor, and pressure sensors in the grasp handle. The advantages of this device are that it is small in size, inexpensive, and available for use at home without specialists supervision. In addition, a novel patient-driven strategy based on the patients movement intention detected by the pressure sensors without bio-signals is introduced. Once the system detects a patients movement intention, it triggers the robotic device to move the patients hand to form the normal grasping behavior. This strategy may encourage stroke patients to participate in rehabilitation training to recover their hand grasp function and it may also enhance neural plasticity. A user study was conducted in order to investigate the usability, acceptability, satisfaction, and suggestions for improvement of the proposed device. The results of this survey included positive reviews from therapists and a stroke patient. In particular, therapists expected that the proposed patient-driven mode can motivate patients for their rehabilitation training and it can be effective to prevent a compensational strategy in active movements. It is expected that the proposed device will assist stroke patients in restoring their grasp function efficiently.

Needle insertion simulator with haptic feedback

We introduce a novel injection simulator with haptic feedback which provides realistic physical experience to the medical user. Needle insertion requires very dexterous hands-on skills and fast and appropriate response to avoid dangerous situations for patients. In order to train the injection operation, the proposed injection simulator has been designed to generate delicate force feedback to simulate the needle penetration into various tissues such as skin, muscle, and blood vessels. We have developed and evaluated the proposed simulator with medical doctors and realized that the system offers very realistic haptic feedback with dynamic visual feedback.

Enhanced hand rehabilitation using a haptic interface

This paper proposes a hand rehabilitation system based on a 1-DOF haptic handle. The system is designed to improve hand strength and movement and provides haptic feedback incorporating visual games. A haptic interface enhances the clinical effect and makes it more fun compared to previous systems. Various haptic effects can be programmed corresponding to the game scenario. Though our target consumers are stroke patients, the elderly can also practice hand functions of ADL to develop cognitive ability and muscular strength.

A wearable device for emotional recognition using facial expression and physiological response

This paper introduces a glasses-typed wearable system to detect users emotions using facial expression and physiological responses. The system is designed to acquire facial expression through a built-in camera and physiological responses such as photoplethysmogram (PPG) and electrodermal activity (EDA) in unobtrusive way. We used video clips for induced emotions to test the system suitability in the experiment. The results showed a few meaningful properties that associate emotions with facial expressions and physiological responses captured by the developed wearable device. We expect that this wearable system with a built-in camera and physiological sensors may be a good solution to monitor users emotional state in daily life.This paper introduces a glasses-typed wearable system to detect users emotions using facial expression and physiological responses. The system is designed to acquire facial expression through a built-in camera and physiological responses such as photoplethysmogram (PPG) and electrodermal activity (EDA) in unobtrusive way. We used video clips for induced emotions to test the system suitability in the experiment. The results showed a few meaningful properties that associate emotions with facial expressions and physiological responses captured by the developed wearable device. We expect that this wearable system with a built-in camera and physiological sensors may be a good solution to monitor users emotional state in daily life.