In this study, we aim to construct a perception-based shape display system to provide users with the sensation of touching virtual objects of varying shapes using only a simple mechanism. Thus far, we have proved that identified curved surface shapes or edge angles can be modified by displacing the visual representation of the user's hand. However, using this method, we cannot emulate multifinger touch, because of spatial unconformity. To solve this problem, we focus on modifying the identification of shapes using two fingers by deforming the visual representation of the user's hand. We devised a video see-through system that enables us to change the perceived shape of an object that a user is touching visually. The visual representation of the user's hand is deformed as if the user were handling a visual object; however, the user is actually handling an object of a different shape. Using this system, we conducted two experiments to investigate the effects of visuo-haptic interaction and evaluate its effectiveness. One is an investigation on the modification of size perception to confirm that the fingers did not stroke the shape but only touched it statically. The other is an investigation on the modification of shape perception for confirming that the fingers dynamically stroked the surface of the shape. The results of these experiments show that the perceived sizes of objects handled using a thumb and other finger(s) could be modified if the difference between the size of physical and visual stimuli was in the −40% to 35% range. In addition, we found that the algorithm can create an effect of shape perception modification when users stroke the shape with multiple fingers.

In this paper, we discuss possible applications of virtual reality technologies, such as immersive projection technology (IPT), in the field of genome science, and propose cluster-oriented visualization that attaches importance to data separation of large gene data sets with multiple variables. Based on these strategies, we developed the cluster overlap distribution map (CDCM), which is a visualization methodology using IPT for pairwise comparison between cluster sets generated from different gene expression data sets. This methodology effectively provides the user with indications of gene clusters that are worth a close examination. In addition, by using the plate window manager system, which enables the user to manipulate existing 2D GUI applications in the virtual 3D space, we developed the virtual environment for the comprehensive analysis from providing the indications to further examination by referring to the database on Web sites. Our system was applied in the comparison between the gene expression data sets of hepatocellular carcinomas and hepatoblastomas, and the effectiveness of the system was confirmed.

The sensations of touch and force have come to be recognized as essential factors in virtual reality, and many efforts have been made to develop display devices that reproduce these sensations. Such devices are divided into two categories: wearing and nonwearing. In this paper, a method is proposed for representing virtual objects of arbitrary shapes using a nonwearing device. Based on this method, a device was fabricated to describe our approach. Our prototype device was designed to approximately represent part of the surface of a virtual object as a tangential surface (i.e., partial surface) to the user's fingertip. The device was implemented as a mechanism with five degrees of freedom that are commonly used to measure the fingertip position and to present the partial surface to the fingertip. The mechanism was controlled through two calculation loops: a model loop that gives a tangential surface from the fingertip position and the shape of objects, and a servo loop that manages the mechanism to represent the given tangential surface by the partial surface. Also, a stereoscopic, head-tracking visual system was implemented to realize the combined presentation of visual information and the partial surface. As an example of the applications of the environment, a task of writing characters was simulated. From the observation of the performance of the task, the presentation of the partial surface was proved to have an effect on decreasing blur and dragging in written characters.

During recent years, the use of virtual reality technology has become widespread and popular. However, to further broaden the application of virtual reality, more sophisticated and realistic virtual worlds need to be developed. Traditionally, most virtual worlds are generated using three-dimensional (3D) computer graphics incorporating 3D geometric models and various rendering software. However, if 3D models become very complex, the delay time caused by rendering calculations makes it difficult for the user to be able to interact with the virtual world. Also, the production of realistic 3D computer graphics is very cost and labor intensive. From a very practical point of view, it is clear that we need some alternate approaches to realize a truly realistic virtual world. In this paper, the authors introduce an alternate method of generating virtual worlds other than 3D computer graphics. The method discussed here is to generate virtual worlds by processing 2D real images taken by video cameras. For this purpose, a special video camera system that can record image data indexed by position data was developed. Using recorded image data indexed by position data we are able to experience the virtual image world interactively. This method has become realistic due to advances in multimedia computers capable of handling large image data. A tested prototype of this kind of system is discussed in some depth, along with the capability and limitations of this prototype system.

The sand play technique (Sandspiel) has often been used in psychological treatments. The primary purpose of this study was to construct a practical virtual environment to support the application of this technique with computers. The prototype application called “Virtual Sand Box” was developed to test the Sand Play Technique in the diagnosis and treatment of autistic patients. The display system and input device are discussed. A detailed description is also provided for how a virtual environment was constructed to cater input systems into output systems in order to facilitate manipulation tasks for the user. Experimental results gave insight into the feasibility and advantages of applying virtual reality technology to clinical medicine, particularly with respect to the diagnosis of the people with psychological and psychiatric sicknesses such as autism and neurosis.