https://pubs.kist.re.kr/handle/123456789/75395 Wed, 15 Apr 2026 16:34:46 GMT 2026-04-15T16:34:46Z https://pubs.kist.re.kr/handle/201004/115001 Title: Robust Binarization of Gray-Coded Pattern Images for Smart Projectors Authors: Choi, Ouk; Ahn, Sang Chul; Lim, Hwasup Abstract: A smart projector, equipped with a camera, automatically adjusts its keystone and color transformation according to the shape, position, orientation, and reflectance of projection surfaces. To realize the automatic adjustment, smart projectors build a mapping between pixel locations in a projector image and their corresponding locations in the camera image of the projected surface. Complementary gray-coded patterns play an important role in building such correspondences; corresponding pixels share the same code, so that correspondence search becomes as simple as reading out the codes. If the camera views a wider area than the projection region, a significant number of camera pixels capture surfaces outside the projection region. To build correct correspondences, detection and rejection of them is indispensable. In this paper, we build a robust method for detecting and rejecting those pixels, so that the camera images of the patterns will be correctly binarized. Experimental results show that the proposed method effectively rejects outliers while preserving accurately binarized pixels. Fri, 01 Jan 2016 00:00:00 GMT https://pubs.kist.re.kr/handle/201004/115001 2016-01-01T00:00:00Z https://pubs.kist.re.kr/handle/201004/115000 Title: Direct and Realistic Handover of a Virtual Object Authors: Kim, Jun-Sik; Park, Jung-Min Abstract: We propose a method to induce a realistic two-hand manipulation of virtual objects by representing their reactions to multiple contacts of hands and fingers in a unified way. One of the key problems in achieving physics-based virtual interaction is that there is no accurate haptic feedback to the user's hands and fingers, which must introduce a mismatch between the real hands and their virtual counterparts. This problem becomes more serious when multiple hands or fingers are involved to a single virtual object, for example, a hand-over situation from one hand to the other. The key contribution of this paper is to represent and describe the physical status of a virtual object in the local object space and to change the status in the object point of view in order to avoid its drastic changes by the physical-virtual mismatch. The experiments compare the performance of the proposed method with objects in different shapes when using 2D and 3D visualization devices. Fri, 01 Jan 2016 00:00:00 GMT https://pubs.kist.re.kr/handle/201004/115000 2016-01-01T00:00:00Z https://pubs.kist.re.kr/handle/201004/114999 Title: A Planar Stable Walking Model based on Ankle Actuation and the Virtual Pendulum Concept Authors: Lee, Jongwoo; Oh, Yonghwan Abstract: In this paper, we propose a novel planar biped model which achieves asymptotically stable walking, based on ankle actuation and the virtual pendulum concept. Simple models for walking have provided useful insights in understanding fundamental principles of human locomotion as well as developing controllers for biped robots. Existing simplest walking models include a point mass with either rigid legs or compliant legs. Both models are able to describe different gaits such as walking and running, but are not able to address posture stabilization, which is another important issue in bipedalism. Recently, the virtual pendulum (VP) concept was proposed as an intuitive posture stabilization strategy and successfully demonstrated on the compliant leg scheme. However, the model does not address inherent peripheral mechanics of walking, i.e., ankle actuation and collisional energy loss from foot-ground interaction. The model proposed in this paper consists of a rigid trunk, rigid legs and ankle actuation. The energy dissipation due to collision and compensation by ankle actuation play an essential role for asymptotically stable walking, while the trunk posture is stabilized based on the VP concept. Nonlinear dynamic simulation verifies that the model constructs a stable limit cycle with a small angular oscillation of trunk. Fri, 01 Jan 2016 00:00:00 GMT https://pubs.kist.re.kr/handle/201004/114999 2016-01-01T00:00:00Z https://pubs.kist.re.kr/handle/201004/114998 Title: Detecting Voluntary Gait Intention of Chronic Stroke Patients towards Top-Down Gait Rehabilitation Using EEG Authors: Choi, Junhyuk; Kang, Hyolim; Chung, Sang Hun; Kim, Yeonghun; Lee, Ung Hee; Lee, Jong Min; Kim, Seung-Jong; Chun, Min Ho; Kim, Hyungmin Abstract: One of the recent trends in gait rehabilitation is to incorporate bio-signals, such as electromyography (EMG) or electroencephalography (EEG), for facilitating neuroplasticity, i.e. top-down approach. In this study, we investigated decoding stroke patients' gait intention through a wireless EEG system. To overcome patient-specific EEG patterns due to impaired cerebral cortices, common spatial patterns (CSP) was employed. We demonstrated that CSP filter can be used to maximize the EEG signal variance-ratio of gait and standing conditions. Finally, linear discriminant analysis (LDA) classification was conducted, whereby the average accuracy of 73.2% and the average delay of 0.13 s were achieved for 3 chronic stroke patients. Additionally, we also found out that the inverse CSP matrix topography of stroke patients' EEG showed good agreement with the patients' paretic side. Fri, 01 Jan 2016 00:00:00 GMT https://pubs.kist.re.kr/handle/201004/114998 2016-01-01T00:00:00Z