https://scholarworks.unist.ac.kr/handle/201301/27 Wed, 08 Apr 2026 21:02:37 GMT 2026-04-08T21:02:37Z https://scholarworks.unist.ac.kr/handle/201301/91242 Title: IrCube tracker: an optical 6-DOF tracker based on LED directivity Author(s): Heo, Seongkook; Han, Jaehyun; Choi, Sangwon; Lee, Seunghwan; Lee, Geehyuk; Lee, Hyong-Euk; Kim, SangHyun; Bang, Won-Chul; Kim, DoKyoon; Kim, ChangYeong Abstract: Six-degrees-of-freedom (6-DOF) trackers, which were mainly for professional computer applications, are now in demand by everyday consumer applications. With the requirements of consumer electronics in mind, we designed an optical 6-DOF tracker where a few photo-sensors can track the position and orientation of an LED cluster. The operating principle of the tracker is basically source localization by solving an inverse problem. We implemented a prototype system for a TV viewing environment, verified the feasibility of the operating principle, and evaluated the basic performance of the prototype system in terms of accuracy and speed. We also examined its application possibility to different environments, such as a tabletop computer, a tablet computer, and a mobile spatial interaction environment. Sat, 15 Oct 2011 15:00:00 GMT https://scholarworks.unist.ac.kr/handle/201301/91242 2011-10-15T15:00:00Z https://scholarworks.unist.ac.kr/handle/201301/91243 Title: Forcetap: extending the input vocabulary of mobile touch screens by adding tap gestures Author(s): Heo, Seongkook; Lee, Geehyuk Abstract: We introduce an interaction technique that increases the touch screen input vocabulary by distinguishing a strong tap from a gentle tap without the use of additional hardware. We have designed and validated an algorithm that detects different types of screen touches by combining data from the built-in accelerometer with position data from the touch screen. The proposed technique allows a touch screen input to contain not only the position of a finger contact, but also its type, i.e., whether the contact is a 'Tap' or a 'ForceTap.' To verify the feasibility of the proposed technique we have implemented our detection algorithm in experiments that test cases of single-handed, two-handed, immersive, and on the move usage. Based on the experimental results, we investigate the advantages of using two types of touch inputs and discuss emerging issues. Finally, we suggest a design guideline for applying the proposed technique to touch screen applications, and present possible application scenarios. Mon, 29 Aug 2011 15:00:00 GMT https://scholarworks.unist.ac.kr/handle/201301/91243 2011-08-29T15:00:00Z https://scholarworks.unist.ac.kr/handle/201301/91241 Title: Force gestures: augmenting touch screen gestures with normal and tangential forces Author(s): Heo, Seongkook; Lee, Geehyuk Abstract: Force gestures are touch screen gestures augmented by the normal and tangential forces on the screen. In order to study the feasibility of the force gestures on a mobile touch screen, we implemented a prototype touch screen device that can sense the normal and tangential forces of a touch gesture on the screen. We also designed two example applications, a web browser and an e-book reader, that utilize the force gestures for their primary actions. We conducted a user study with the prototype and the applications to study the characteristics of the force gestures and the effectiveness of their mapping to the primary actions. In the user study we could also discover interesting usability issues and collect useful user feedback about the force gestures and their mapping to GUI actions. Sat, 15 Oct 2011 15:00:00 GMT https://scholarworks.unist.ac.kr/handle/201301/91241 2011-10-15T15:00:00Z https://scholarworks.unist.ac.kr/handle/201301/91240 Title: ForceDrag: using pressure as a touch input modifier Author(s): Heo, Seongkook; Lee, Geehyuk Abstract: It is common to use modifier keys in a PC environment in order to change drag modes, but mobile devices with a touch screen do not provide this option. Thus, we present ForceDrag to address this issue, which is a touch drag operation where pressure is used as a modifier key to change touch drag modes. We also introduce the concept of force lock and we compare three selection techniques for performing a force lock in a user study. We also describe a prototype implementation and discuss early user feedback on ForceDrag. Sun, 25 Nov 2012 15:00:00 GMT https://scholarworks.unist.ac.kr/handle/201301/91240 2012-11-25T15:00:00Z