This paper describes the development and evaluation of a tactile hybrid interface of verbal and nonverbal communication, which informs Deaf-Blind people of their position and direction in real-time through the tactile sensation by Finger-Braille method. Finger-Braille is one of the great commonly used communication methods among the Deaf-Blind people in Japan. We psychologically show the subjects felt tactile stimulation transmitting by the interface as simultaneous stimulation, by measuring delay of stimulus signal between both hands caused by wireless connection and time discrimination threshold of both hands. We propose a new wayfinding system using the combination of verbal and nonverbal information using the proposed interface, and verify the feasibility of instructing the correct orientation by using tactile stimulation pattern through experiments.

View full abstract

This paper describes a haptic controller for force feedback system. It is necessary that the frequency of device control is higher than 1kHz. Standard PC environments, however, have no real time operating system, and PC also controls the virtual world simultaneously. Therefore, it is difficult to guarantee the quality of frequency. On the other side, a virtual wall is generally implemented in impedance control with spring-damper model. In the case of usual 1kHz control, high impedance virtual wall is oscillated. When we display very stiff virtual wall, we try to get the parameters of maximum stable impedance, but the virtual wall displayed with these parameters can not satisfy user's request. In this research,we have developed the High Definition Haptic Controller with SuperH4 processor, and put this controller between the PC and the haptic device for the function distribution and the quality of frequency. In order to realize high frequency of device control, the controller also complements haptic information from primitive geometry and impedance of virtual wall. The SPIDAR, wire driven haptic display, is implemented in this controller, and it realizes 10kHz control frequency. Consequently, it became possible to display a very hard and high-resolution virtual wall stably. This means that the High Definition Haptic Controller presents stable haptic and high quality sensation in the virtual environments.

View full abstract

In this paper, we introduce "network visual haptizing(NVH)" as a concept to display real world information using tactile pattern displays. "Network visual haptizing" is a concept that visual information is converted into tactile display information via network. A bidirectional NVH system on which we can touch the other's finger virtually is developed and the network communication results are shown. We also introduce "tactile skin" as a concept for transforming best suited haptic/tactile information from visual information, and several "tacltile skin"s are implemented on the NVH system.

View full abstract

It is necessary to ascertain the texture perception mechanism of humans in developing tactile devices that create or detect lifelike texture. In other words, we need to clarify what sort of information (stimulus) has to be combined and applied to the human skin to be recognized as texture of real material. In this paper, the relationship between object surface physicality and texture perception is discussed through multivariate analysis. We often quantified the tactile sense and texture perception through sensory evaluation. From the results, we built a model of the relationship. This model helps derive the tendency toward different types of texture such as metal, wood, plastic, fabric, etc., from object surface physicality; surface roughness, heat transfer property, and modulus of elasticity.

View full abstract

In this paper, a system integrated haptic and audio sensation called AudioHaptics was proposed. It can generate those senses by using not pre-recorded sound but a physical model and by using a haptic interface (HapticMaster) that is equipped with a speaker at the end effecter. By using this system, the user can recognize inner structure, hardness, and quality of material. By the way, we usually rely on visual sensation mainly on recognition of object, and it is known as visual dominance. In this paper, auditory and haptic sensations were focused on. In particular, the effect between auditory and haptic sensations on user's perception of the hardness of a virtual surface was investigated. As a result, haptic dominance was confirmed as using auditory and haptic sensation.

View full abstract

In order to investigate tactile perception characteristics of the human fingerpad for optimal designs of sensory substitution devices, we developed a small piezoelectric bimorph actuator whose frequency characteristics were kept flat in tactilely perceivable frequency range. The parameters for the design of the bimorph were determined by using a mechanical simulation model of the piezoelectric bimorph and the finger skin. To evaluate the performance of the bimorph, we measured frequency-displacement relationships when the fingerpad was vibrated by the piezoelectric bimorph. The experimental results showed that the frequency-displacement relationships were almost the same as the estimation obtained from the mechanical simulation model. The developed bimorph should be able to generate various but precise skin displacement patterns onto a fingerpad in accordance with the wave form of the input voltage to the bimorph.

View full abstract

This paper describes sensory integration using the Food Simulator. A taste of a food arises from mixture of auditory, chemical, and force sensation. The food simulator generates a food texture according to the force profile captured from a user's biting force of a real food. By development of the Food Simulator, we can extract only texture from taste. We experimented in sensory integration by displaying texture, sound, smell and taste. Our goal is to study integration among sensory modalities regarding a taste of a food.

View full abstract

Recently, various types of display system can present aural, visual and haptic information related to the position. Also, it is important to present olfactory information related to the position, and we focus on the spatiality of olfaction. Olfactory information consists of the kind and density of an odorous molecule. And, human can know the position of an odor source, by perceiving the density distribution of the odorous molecule. In this research, we constructed and evaluated wearable olfactory display to present the spatiality of olfaction at outdoor environment. By simulating density distribution of the odorous molecule based on diffusion equation, we generate two types of olfactory field which represented olfactory information related to the position. According to positions of user and odor source, our prototype system control density of odorous molecule and blow generated odor air to the user's nose. By using the proposed system, user can specify position of odor source in outdoor environment. Also, the user can feel as if he/she passed each other with the perfumed people.

View full abstract

Braille displays have been used to present symbolic information to blind person's finger tips. However, these displays could not convey schematic information such as figures. For the presentation of schematic information, we need to develop tactile display that consists of pin array of higher resolution. To attain higher resolution we propose a novel actuation mechanism using low melting point metal. The low melting point metal is used to fix each pin; usually, the pin is clutched because the metal is solid, once the metal is melted by a heater, the pin is released and pushed up or down using compressed air. We implemented prototype display devices that has 10x10 pin array, whose interval is 2mm and pin diameter is 0.5mm, actuated by the proposed mechanism, and evaluated the characteristics of the devices.

View full abstract

We propose a new encounter-typed haptic display which is constructed with three motors, three wires and three sliders. An end effector of the haptic display is held with the wires which are rolled by the motors, and the sliders which move the motors. When a fingertip measured by stereo camera touches on surface of a virtual model, the end effector exists in its position. Since the end effector mass is small, it is safe and its response is high. And since 5 flexibility is realized with three wires, the wires do not interfere to the operator's hand. So in the experiments, we checked its usefulness.

View full abstract

Recently, virtual reality technology has been able to provide realistic world with various sensations such as virtual, aural and haptic senses. However, human beings have olfactory sensation, which gather various kinds of external information and judge a situation out of them. So, it is important to transmit and present sense of smell in virtual environment and tele-existence. In this paper, we develop an olfactory transmission system, olfactory display and sensing system. By using three gas sensors and matching database, the sensing system can identified input smells and detect its intensity. By translating obtained olfactory information, user can get proper olfaction through the display system. Also we evaluate our prototype system in terms of response time and sensing precision.

View full abstract

Human anticipation property of a free-falling object was experimentally studied by using a VR system, and the obtained results were compared to the results in real environment. Twelve participants were required to answer the anticipated position of free-falling virtual object at the visual stimulus onset, which was given after a specific interval of the object disappearance. The anticipated position increased proportionally to the interval, while the interval was varied from 30 to 190 ms. However, the slopes of the regression lines, which represent the anticipated velocities of the subjects, were five times smaller than the actual velocities. This unexpected slowdown was independent from the distance in virtual space. Therefore, this slowdown appears to be caused by the internal process of the recognition and anticipation, not the physical limitation such as the eye movement velocity.

View full abstract

Digital archiving of cultural heritages has recently been broadening in the way of using them. However such digital contents are only shown in display, and cannot be touched. In this paper, we propose a system that displays textures of the digital contents on real objects via video-see-through HMD, so that we can touch the digital archives in the real world. The textures are deformed by an appropriate geometric transformation, and overlaid onto the deformable surface of the object in real time. For demonstrating the effectiveness of the proposed system, we develop a system that displays digitally scanned images of rare books on paper surface on blank books.

View full abstract

In order to represent different states of materials in a mathematical form, their precise dynamical analysis is given according to their physical characteristics including their irreversible transformation. The real time operation to their virtual materials by a saw-type edged tool is discussed for their force display system. On the basis of our previous studies, the practical analysis method with more degrees of freedom and less calculation is proposed for well attendance to the reality of cutting them by the saw-type edged tool. Consequently, it ensures the better real time simulation results in accordance with the experiences of their physical operation.

View full abstract

This paper proposes a design method of a dome type multi projection display "CyberDome" which presents a distortion-free, life-size, and stereoscopic images and is wide enough to cover the field of user's vision with a large hemi spherical screen. We have developed the software named "Projection Simulator" to design multi projector arrangements against a dome screen and to make multi images continuous and seamless by tuning parameters of projection model. We also have developed the algorithm to specify boundary areas of images and to make brightness correction filters. Actually we built a system with a dome screen of 8.25m diameter and 1 8 projectors, where many people can experience seamless, high-resolution stereoscopic images simultaneously, and we confirmed our design method.

View full abstract