Geehyuk Lee

Geehyuk Lee
Korea Advanced Institute of Science and Technology | KAIST · School of Computing

PhD

About

150
Publications
22,093
Reads
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1,910
Citations
Citations since 2016
57 Research Items
1295 Citations
2016201720182019202020212022050100150200250300
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2016201720182019202020212022050100150200250300
2016201720182019202020212022050100150200250300
Education
September 1995 - December 2000
University of Pennsylvania
Field of study
  • Electrical Engineering
March 1990 - February 1992
March 1986 - February 1990

Publications

Publications (150)
Preprint
Full-text available
Non-verbal behavior is essential for embodied agents like social robots, virtual avatars, and digital humans. Existing behavior authoring approaches including keyframe animation and motion capture are too expensive to use when there are numerous utterances requiring gestures. Automatic generation methods show promising results, but their output qua...
Article
For human-like agents, including virtual avatars and social robots, making proper gestures while speaking is crucial in human-agent interaction. Co-speech gestures enhance interaction experiences and make the agents look alive. However, it is difficult to generate human-like gestures due to the lack of understanding of how people gesture. Data-driv...
Preprint
Full-text available
For human-like agents, including virtual avatars and social robots, making proper gestures while speaking is crucial in human--agent interaction. Co-speech gestures enhance interaction experiences and make the agents look alive. However, it is difficult to generate human-like gestures due to the lack of understanding of how people gesture. Data-dri...
Conference Paper
Promisingly, driving is adapting to a Voice User Interface (VUI) that lets drivers utilize diverse applications with little effort. However, the VUI has innate usability issues, such as a turn-taking problem, a short-term memory workload, in efficient controls, and difficulty correcting errors. To over come these weaknesses, we explored supplementi...
Article
Despite the emergence of advanced technologies, the behavioural complexities remain underexplored, especially from the viewpoint of their potential in interactive installations. This study aims to explore the future interactivity of an agent’s behaviour by envisioning speculative future human operations using a human-controlled interactive installa...
Conference Paper
Indirect writing interface is currently widely used for handwriting text entry with a pen, however, it may cause additional eye and hand movement. Gu and Lee suggested a revival of the concept of direct writing and they showed the potential of the direct writing interface in editing text. In this demo, we demonstrate an In-Place Ink text editor pro...
Conference Paper
There are needs for pen interaction on a laptop, and the market sees many pen-enabled laptop products. Many of them can be transformed into tablets when pen interaction is needed. In a real situation, however, users use multiple applications simultaneously, and such a convertible feature may not be useful. We introduce MirrorPad, a novel interface...
Conference Paper
Text entry is expected to be a common task for smart glass users, which is generally performed using a touchpad on the temple or by a promising approach using eye tracking. However, each approach has its own limitations. For more efficient text entry, we present the concept of gaze-assisted typing (GAT), which uses both a touchpad and eye tracking....
Conference Paper
A watch-back tactile display (WBTD) is an attractive output option due to its always-available nature. However, employing commonly-used vibration modality on a WBTD may result in a low efficiency since its stimulation area is relatively wide compared with the small contact area of a watch-back. We considered using a more localized tactile stimulus,...
Conference Paper
In countries where languages with non-Latin characters are prevalent, people use a keyboard with two language modes namely, the native language and English, and often experience mode errors. To diagnose the mode error problem, we conducted a field study and observed that 78% of the mode errors occurred immediately after application switching. We im...
Conference Paper
Full-text available
Interacting with a smartwatch is difficult owing to its small touchscreen. A general strategy to overcome the limitations of the small screen is to increase the input vocabulary. A popular approach to do this is to distinguish fingers and assign different functions to them. As a finger identification method for a smartwatch, we propose FingMag, a m...
Conference Paper
Two-Thumb Touchpad Typing (4T) using hand-held controllers is one of the common text entry techniques in Virtual Reality (VR). However, its performance is far below that of two-thumb typing on a smartphone. We explored the possibility of improving its performance focusing on the following two factors: the visual feedback of hovering thumbs and the...
Conference Paper
Tap-typing with a pen on a virtual keyboard is often used for intermittent text entry on a pen-equipped tablet; however, this has usability issues owing to the large size of the virtual keyboard. We speculated that tap-typing with a pen on a tablet may not require such a large keyboard, but there was no empirical study to help us to determine the b...
Conference Paper
Full-text available
As tablet computers are hosting more productivity applications, efficient text entry is becoming more important. A soft keyboard, which is the primary text entry interface for tablets, however, often competes with applications for the limited screen space. A promising solution to this problem may be a semi-transparent soft keyboard (STK), which can...
Conference Paper
The QWERTY keyboard has a wide form factor, whereas smartwatches frequently have round or square form factors. Even if extra space for an input field is considered, the aspect ratio of the QWERTY keyboard may not be optimal for a round or square smartwatch. We surmised that a narrower keyboard would be better able to utilize the screen area of a ro...
Preprint
Full-text available
Co-speech gestures enhance interaction experiences between humans as well as between humans and robots. Existing robots use rule-based speech-gesture association, but this requires human labor and prior knowledge of experts to be implemented. We present a learning-based co-speech gesture generation that is learned from 52 h of TED talks. The propos...
Conference Paper
We demonstrate a haptic feedback method to generate multiple virtual textures on analog buttons of the gamepad. The method utilizes the haptic illusion evoked from proper haptic cues in respect of the analog button's movement to change the perceived physical property of the button. Two types of analog buttons, joystick and trigger button on the gam...
Conference Paper
We present Touch180, a computer vision based solution for identifying fingers on a mobile touchscreen with a fisheye camera and deep learning algorithm. As a proof-of-concept research, this paper focused on robustness and high accuracy of finger identification. We generated a new dataset for Touch180 configuration, which is named as Fisheye180. We...
Conference Paper
As smartwatch functions expand, target selection among many items will probably become a common task. List search interfaces (LSIs) for a smartwatch use a prefix matching query to search for items, and need two modes because of the small screen size: query input mode and list navigation mode. Despite the modes, LSIs may be more efficient than list...
Conference Paper
Interpersonal touch, one of the most primitive social languages, is an excellent design element frequently used in interaction design. In this paper, we present a richer understanding of it by using spatial factors and social relations among people, which has rarely been explored in interactive systems. We designed an interactive installation calle...
Conference Paper
We present a new handheld haptic device, Thor's Hammer, which uses propeller propulsion to generate ungrounded, 3-DOF force feedback. Thor's Hammer has six motors and propellers that generates strong thrusts of air without the need for physical grounding or heavy air compressors. With its location and orientation tracked by an optimal tracking syst...
Conference Paper
A tactile display on the back of a smartwatch is an attractive output option; however, its channel capacity is limited owing to the small contact area. In order to expand the channel capacity, we considered using two perceptually distinct types of stimuli, wind and vibration, together on the same skin area. The result is a multimodal tactile displa...
Conference Paper
Watch-back tactile display is a tempting output option to support a smartwatch. However, a single modal tactile display has a limited channel capacity owing to the small contact area and the limited spatial resolution of the skin. To expand the information bandwidth, we considered combining multiple tactile stimuli that are perceptually distinct. A...
Conference Paper
We present Thor's Hammer - an ungrounded force feedback device. Thor's Hammer consists of a cube-shaped structure and a handle. To generate 3-DOF force feedback, six motors and propellers installed on the cube project air in six directions that are normal to each face of the cube-shaped structure. Tracked in 6-DOF by an optical tracking system, Tho...
Conference Paper
We demonstrate a haptic feedback method that generates a compliance illusion on a rigid surface with a tangential force sensor and a vibrotactile actuator. The method assumes a conceptual model where a virtual object is placed on a textured surface and stringed to four walls with four springs. A two dimensional tangential force vector measured from...
Conference Paper
Small touchscreen interfaces such as a smartwatch have usability problems due to the small screen. One solution to these problems is to utilize the space around the smartwatch as continuous input space for the touchscreen interface. We defined four steps for a gesture that starts on the touchscreen and continues in the air. The goal of this definit...
Conference Paper
While smart glasses make information more accessible in mobile scenarios, entering text on these devices is still difficult. In this paper, we suggest using a smartwatch as an indirect input device for smart glasses text entry. With the watch-glasses combination, users do not need to lift the arm to touch the glasses nor need to carry a special ext...
Conference Paper
Full-text available
This paper reviews and categorizes the most common types of selfie sticks available in the market and discusses their design and usability. Through a theoretical analysis, it demonstrates how most commercial selfie sticks ignore important human factors, including ergonomics. It, then, presents results of an online survey, where selfie stick users (...
Article
Researchers are proposing many approaches to overcome the usability problem of a smartwatch owing to its small touchscreen. One of the promising approaches is to use touch-sensing edges to expand the control space of a smartwatch. We considered possible interaction techniques using touch-sensing edges in combination with the smartwatch touchscreen:...
Conference Paper
Despite the advantages of instant messaging (IM) such as simple and fast messaging, IM cannot be considered as effective as face-to-face actual conversation. The current message-by-message interface shows a gap with actual conversation in terms of temporal structure and information dimension levels. Our study investigated the real-time text-display...
Conference Paper
We explored new interaction scenarios that can be realized when a touchpad outputs fast and high-resolution spatio-temporal tactile patterns to the touch-sensitive skin on the fingertips of a user. We first constructed a special tactile multi-touch touchpad called PinPad, which was capable of outputting fast and high-resolution tactile patterns usi...
Article
Two-finger operations, such as rotation operations and zoom operations, are now standard touchscreen operations. However, these two-finger operations may pose an ergonomic problem when they are performed with one hand. FingerSkate is an interaction technique to mitigate the ergonomic problem of two-finger operations adopting the concept of gesture...
Article
As an option for remote text entry, we explored the possibility of bimanual text entry using a touchpad, that we call two-thumb touchpad typing (4 T). The design of a 4 T interface presents a few important design options to examine, and one of them is a target selection method. In this study, we designed two 4 T interfaces, called SlideType and Fly...
Conference Paper
Whereas hotkeys are an important user interface for PCs, they are not usually available for touchscreen tablets. We present MelodicTap, a novel hotkey technique utilizing fingering gestures for touchscreen tablets. Users can access a hierarchical menu by performing consecutive sequential taps on the touchscreen. MelodicTap has the following advanta...
Conference Paper
Full-text available
An indirect handwriting interface using a separate window is a de facto standard interface in most of major pen computing systems. In this paper, we study the potential of the other less explored handwriting interfaces, which we call In-Place-Ink (IPI) interfaces, where a user writes directly on a target text input area. We first conducted a prelim...
Conference Paper
Traditional wearable tactile displays transfer tactile stimulations through a firm contact between the stimulator and the skin. We conjecture that a firm contact may not be always possible and acceptable. Therefore, we explored the concept of a non-contact wearable tactile display using an airflow, which can transfer information without a firm cont...
Article
This paper presents a method to generate a haptic illusion of compliance using a vibrotactile actuator when a tangential force is applied to a rigid surface. The novel method builds on a conceptual compliance model where a physical object moves on a textured surface in response to a tangential force. The method plays vibration patterns simulating f...
Conference Paper
We introduce TapBoard 2, a touchpad-based keyboard that solves the problem of typing and pointing disambiguation. The pointing interaction design of TapBoard 2 is nearly identical to natural touchpad interaction, and its shared workspace naturally invites bimanual pointing interaction. To implement TapBoard 2, we developed a novel gesture represent...
Conference Paper
We present a new smart-restorable backspace technique to facilitate correction of "overlooked" errors on touchscreen-based tablets. We conducted an empirical study to compare the new backspace technique with the conventional one. Results of the study revealed that the new technique improves the overall text entry performance, both in terms of speed...
Article
The QWERTY keyboard has been a de facto standard for computer text entry and continues to be one for mobile text entry such as for smartphones. It is not clear, however, that it will continue to be an option for text entry for much smaller devices such as smartwatches. In a series of user experiments, we examined the performance of the QWERTY keybo...
Conference Paper
Full-text available
Using multiple sensor-embedded devices enables detection of usage contexts that extend new interaction opportunities (e.g., a gesture and posture composite interface). In this study, we explored a design space of contextual interactions using a mobile device and two wrist-worn devices, suggesting Mo-Bi, the bimanual posture-based mobile interface s...
Conference Paper
" A page transition operation on touch interfaces is a common and frequent subtask when one conducts a drag-like operation such as selecting text and dragging an icon. Traditional page transition gestures such as scrolling and flicking gestures, however, cannot be conducted while conducting the drag-like operation since they have a confliction. We...
Conference Paper
Text entry on a smartwatch is a challenging problem due to the device's limited screen area. In this paper, we introduce the SplitBoard, which is a soft keyboard designed for a smartwatch. As the user flicks left or right on the keyboard, it switches between the left and right halves of a QWERTY keyboard. We report the results of two user experimen...
Conference Paper
A watch-back tactile display (WBTD) is expected to be a viable supplement to the user interface limitations of a smartwatch. However, its design requires that many design parameters such as tactor types and stimulus patterns be determined. We conducted a series of experiments to explore the design space of a WBTD consisting of 3×3 tactors. We demon...
Conference Paper
In order to cope with usability problems of touch gestures caused by the small touchscreen size of a smartwatch, we propose a concept, named Transture, which relaxes the spatial constraints of touch gestures on the small screen by allowing them to continue beyond the screen border into the air. We designed three Transture examples for panning, zoom...
Article
Full-text available
The two main tasks of a smart TV GUI are menu navigation and free pointing. Traditional remotes with directional keys are suitable for menu navigation but may not be so for free pointing. More recent remotes with a two-dimensional (2D) pointing device are suitable for free pointing but may not be so for menu navigation. To support both types of tas...
Article
@KAIST, a human-computer interaction (HCI) laboratory focuses on developing new interaction techniques for new types of computers. It makes new hardware and hack existing hardware to explore design possibilities that go beyond the constraints of current hardware. It also focuses on addressing the user interface problems introduced by new computing...
Article
This paper describes new tactile feedback patterns and the effect of their input performance for a button GUI activated by a tap gesture on mobile touch devices. Based on an analysis of touch interaction and informal user tests, several tactile feedback patterns were designed. Using these patterns, three user experiments were performed to investiga...
Article
Although reliefs are frequently used to add patterns to product surfaces, there is a lack of interaction techniques to model reliefs on the surface of virtual objects. We adopted the repoussé and chasing artwork techniques in an alternative interaction technique to model relief on virtual surfaces. To support this interaction technique, we develope...
Article
A drag operation is used for many two-point functions in mouse-based graphical user interfaces (GUIs), but its usage in touchscreen GUIs is limited because it is mainly used for scrolling. We propose Push-Push as a second two-point touchscreen operation that is not in conflict with a drag operation. We implemented three application scenarios and sh...
Conference Paper
Sliding is one of the basic touchscreen operations, but is mainly used for scrolling in mobile touchscreen GUIs. As a way to share sliding operations among scrolling and other GUI functions, we propose Slack-Scroll. We implemented two application scenarios of Slack-Scroll, and asserted their feasibility in a user study. All participants could accep...
Article
Full-text available
Interactivity is a unique forum of the ACM CHI Conference that showcases hands-on demonstrations, novel interactive technologies, and artistic installations. At CHI 2014, we aimed to create a "one of a CHInd" Interactivity experience with more than 60 interactive exhibits to highlight the diverse group of computer scientists, sociologists, designer...
Conference Paper
Transparent display has already become an icon of the future. It is described in fancy ways in many movies; its transparency provides compelling visual openness. However, if every monitor is see-through, you would find yourself facing practical problems immediately after you start working with one of them. When you are writing e-mail, everything yo...
Article
Researchers have proposed various techniques for over-the-surface interaction using pens. However, current pen systems can't properly support these techniques because of their limited tracking abilities. The IrPen, an extension of the IrCube tracker, is a six-degree-of-freedom pen system that properly supports over-the-surface interaction on tablet...
Conference Paper
Full-text available
In recent years, touch screens have emerged and matured as the main input interface for mobile and tablet computers calling for extended touch input possibilities. In this paper, we explore the use of consecutive distant taps to expand the touch screen input vocabulary. We analyzed time intervals and distances between consecutive taps during common...
Article
Today, transparent display technologies are becoming quite ubiquitous. However, until now, transparent displays have been used from only one side of the display in limited application areas. In this paper, we propose TransWall, a transparent display that can be used from both sides in order for people to experience co-located, face-to-face interact...
Article
Relief is often used to add patterns to product surfaces, but interaction techniques for modeling relief on the surface of virtual objects have not received due attention. We adopt the repoussé and chasing artwork techniques in an alternative interaction technique for modeling relief on virtual surfaces. To support the interaction technique, we dev...
Conference Paper
The touchpad is the de facto standard input device for controlling the GUI on portable computers. Most touchpads detect only finger contact and ignores other physical actions, such as applying force or hovering over the device. In this paper, we introduce a novel touchpad capable of tracking finger hover and measuring normal and shear forces. We al...
Conference Paper
As touch-based interfaces become more popular, there are attempts to enhance the touch interface by making the interface more sensitive to the finger. This means that touch surfaces not only sense the location of a finger contact, but also other properties such as a finger hover or the applied force. In this chapter, we summarize the properties of...
Conference Paper
Multi-touch operations are sometimes difficult to perform due to musculoskeletal constraints. We propose FingerSkate, a variation to the current multi-touch operations to make them less constrained and more continuous. With FingerSkate, once one starts a multi-touch operation, one can continue the operation without having to maintain both fingers o...
Conference Paper
Full-text available
In this paper, we present a haptic feedback method for a virtual button based on the force-displacement curves of a physical button. The original feature of the proposed method is that it provides haptic feedback, not only for the "click" sensation but also for the moving sensation before and after transition points in a force-displacement curve. T...
Conference Paper
Tapping on the same point twice is a common operation known as double tap, but tapping on distant points in sequence is underutilized. In this poster we explore the potential uses of consecutive distant tap operations, which we call Ta-Tap. As a single-touch operation, it is expected to be particularly useful for single-handed touch screen use. We...
Conference Paper