Byounghyun Yoo

KAIST interactive bicycle simulator

This paper presents key technologies and system integration issues of the KAIST interactive bicycle simulator. The rider on the bicycle feels the motion and has the visual experience as if he/she is riding in the campus of the Korea Advanced Institute of Science and Technology. The simulator consists of a bicycle, a Stewart platform, a magnetorheological handle, a pedal resistance system to generate motion feelings, a real-time visual simulator and projection system, sub-controllers and an integrating control network.

Image‐Based Modeling of Urban Buildings Using Aerial Photographs and Digital Maps

A VR (virtual reality) simulator which is used for helicopter simulations requires a virtual environment of real world urban areas. However, real urban environments are continuously changing. It is necessary to develop a modeling method that makes direct use of GIS (geographical information system) data which is updated periodically. A flight simulation needs to visualize not only buildings in the near distance but also a large number of buildings in the far distance. We propose a method for modeling urban environments from aerial images and digital maps with relatively little manual work. An image-based method is applied to the urban modeling that considers the characteristics of Korean cities. Buildings in the distance can be presented without creating a large number of polygons. The proposed method consists of a pre-processing stage that prepares the model from the GIS data and a modeling stage that creates the virtual urban environment. The virtual urban environment utilizes the height map of buildings.

A framework for a multi-sensory VR effect system with motional display

Virtual reality simulators have been developed as tools for the transfer of knowledge and education. Concurrently, the demand for exhibition systems of science education and cultural experiences has also increased. Existing VR (virtual reality) simulators, which are based on the calculation of dynamics equations, cannot easily be adapted to changes in simulation content. In order to transfer knowledge and maintain interest through educational applications, an experiential system that has multi-sensory effects as well as motion effects is needed. The authors proposed a method for motion generation that is tailored to riding systems and multi-sensory VR effects. In this study, both sense of motion, which is generated from movement of the viewpoint of the visual image, and motion effects, which are prepared in advance, are blended to realize motion simulation by the proposed method. Motion effects can easily be added by interaction between the user and the riding system. Various sensory cues are also implemented to the riding system

An Underwater Vehicle Simulator with Immersive Interface using X3D and HLA

Training war fighters how to maneuver a submarine is very important, but the use of real submarines in such training is expensive and hindered by regional and temporal limitations. Modeling and simulation (M&S) can be a good alternative to costly training. However, the use of existing M&S for submarines has limitations. For instance, the commercial software and hardware need to be kept in a secure place. Depending on the location of the protected software, war fighters may travel far and take a considerable amount of time to get to these places. Long-distance travel also means they have a limited amount of time to train on the M&S machines. Furthermore, many types of M&S have only a one-channel display system, which reduces immersiveness. Another problem is that few heterogeneous simulators can be used as an integrated system. One solution to these problems involves the use of extensible 3D (X3D) graphics, a platform-independent and open standard graphic file format, which can be used with general purpose PCs. The immersiveness is increased by means of a multichannel display system and a motion chair. Finally, the individual components of a simulator can be integrated with the high level architecture and run time infrastructure (HLA/RTI). We demonstrate the proposed method through experiments with an underwater vehicle simulator.

Representation of Urban Buildings Using Modified Relief Mapping

This paper describes the real-time mapping displacement of buildings onto the polygon model of base terrain of geo-spatial information. The buildings are represented as height maps, leading to low memory requirements and not involving changes of the original geometry (i.e., no vertices are created or displaced). The displacement of buildings is mapped toward the protruding direction. The base of texture which represents the ground in topography is correctly mapped onto base polygon without any distortion. This approach can exhibit the correct occlusions between buildings and ground due to parallax and correct self-occlusion.

Silhouette management for protruded displacement mapping

We present a technique to manage the silhouette of objects protruding from the surface without polygonal modeling of the object shape. The technique can represent the correct silhouette and the parallax of protruding shapes by solving the overflow problem that frequently occurs in image-based displacement mapping approaches.