Wearable Haptic Device Presenting Sensations of Fingertips to the Forearm.

Several existing haptic displays used in virtual reality (VR) environments present haptic sensations generated by the fingertips in the VR to actual fingertips. However, these devices face certain challenges, such as physical interference between the devices, particularly when multi-degree-of-freedom (DOF) force needs to be presented to multiple fingers. To address this issue, we propose a haptic presentation method that transmits haptic sensations generated by the fingertips in the VR, including the direction of the force, to the forearm.

Characterization of an Electrode-Type Tactile Display Using Electrical and Electrostatic Friction Stimuli.

Unlike tactile displays that use mechanical actuators, electrode-type tactile displays can be easily integrated and miniaturized because they consist of electrodes and insulators. Electrical tactile displays only require electrodes and use an electric current to stimulate vibration or pressure. Likewise, electrostatic friction tactile displays also only require electrodes and an insulator and can induce changes in friction between the display and a fingerpad.

Brain networks underlying the processing of sound symbolism related to softness perception.

Unlike the assumption of modern linguistics, there is non-arbitrary association between sound and meaning in sound symbolic words. Neuroimaging studies have suggested the unique contribution of the superior temporal sulcus to the processing of sound symbolism. However, because these findings are limited to the mapping between sound symbolism and visually presented objects, the processing of sound symbolic information may also involve the sensory-modality dependent mechanisms.

The Hanger Reflex: An Inexpensive and Non-invasive Therapeutic Modality for Dystonia and Neurological Disorders.

The hanger reflex is a phenomenon characterized by the involuntary rotation of the head when a wire hanger is worn around the head such that a force is applied to the frontal temporal area by the longer side of the hanger. The application of a shearing force on the skin is thought to be the cause of this phenomenon. Attempts have been made to treat cervical dystonia using equipment designed to induce the hanger reflex.

Assessment of Stickiness with Pressure Distribution Sensor Using Offset Magnetic Force.

The quantification of stickiness experienced upon touching a sticky or adhesive substance has attracted intense research attention, particularly for application to haptics, virtual reality, and human-computer interactions. Here, we develop and evaluate a device that quantifies the feeling of stickiness experienced upon touching an adhesive substance. Keeping in mind that a typical pressure distribution sensor can only measure a pressing force, but not a tensile force, in our setup, we apply an offset pressure to a pressure distribution sensor and measure the tensile force generated by an adhesive substance as the difference from the offset pressure.

Pilot feasibility study of a semi-automated three-dimensional scoring system for cervical dystonia.

The objective of this study is to test the feasibility of a semi-automated scoring system for the Toronto Western Spasmodic Torticollis Scale (TWSTRS) severity scale in patients with cervical dystonia. The TWSTRS requires training and experience. We previously developed a system to measure neck angle by analyzing three-dimensional position, obtained using Kinect, a marker-less three-dimensional depth sensor.

Fundamental Perceptual Characterization of an Integrated Tactile Display with Electrovibration and Electrical Stimuli.

Tactile displays have been widely studied for many decades. Although multiple tactile stimuli are more effective to improve the quality of the presented tactile sensation, most tactile displays provide a single tactile stimulus. An integrated tactile display with electrovibration and electrical stimuli is proposed herein.

Brain networks underlying tactile softness perception: A functional magnetic resonance imaging study.

Humans are adept at perceiving physical properties of an object through touch. Tangible object properties can be categorized into two types: macro-spatial properties, including shape and orientation; and material properties, such as roughness, softness, and temperature. Previous neuroimaging studies have shown that roughness and temperature are extracted at nodes of a network, such as that involving the parietal operculum and insula, which is different from the network engaged in processing macro-spatial properties.

Wearable Tactile Display Based on Thermal Expansion of Nichrome Wire.

A wearable tactile display needs to be compact and lightweight, and ideally should be able to present vibration, force, and temperature information to the hand. In many contexts spatially distributed tactile information is needed such as when identifying the shape of objects. In this paper, a multi-element tactile display is described based on the thermal expansion and contraction of nichrome wire.

Evaluation of Electrovibration Stimulation with a Narrow Electrode.

Recently, electrovibration tactile displays were studied and applied to several use cases by researchers. The high-resolution electrode for electrovibration stimulus will contribute to the presentation of a more realistic tactile sensation. However, the sizes of the electrodes that have been used thus far are of the millimeter-order.

Pilot Study of a Device to Induce the Hanger Reflex in Patients with Cervical Dystonia.

The hanger reflex (HR) is an involuntary head rotation that occurs in response to a clothes hanger encircling the head and compressing the unilateral fronto-temporal area. Here, we developed an elliptical device to induce the HR and examined its utility for the treatment of cervical dystonia (CD). The study included 19 patients with rotational-type CD.

Vibration Feedback Latency Affects Material Perception During Rod Tapping Interactions.

We investigated the effect of vibration feedback latency on material perception during a tapping interaction using a rod device. When a user taps a surface, the perception of the material can be modulated by providing a decaying sinusoidal vibration at the moment of contact. To achieve this haptic material augmentation on a touchscreen, a system that can measure the approach velocity and provide vibration with low latency is required.

Comparative Evaluation of Tactile Sensation by Electrical and Mechanical Stimulation.

An electrotactile display is a tactile interface that provides tactile perception by passing electrical current through the surface of the skin. It is actively used instead of mechanical tactile displays for tactile feedback because of several advantages such as its small and thin size, light weight, and high responsiveness. However, the similarities and differences between these sensations is still not clear.

Effect of Dynamic Temperature Stimulus to Plantar Surface of the Foot in the Standing Position.

We have previously found that a vertical force or tactile sensation occurs when the temperature of a participant's skin changes rapidly. In this illusion, upward motion, pressure, or force sensation is elicited when stimulus temperature rises rapidly, whereas in the opposite case, downward motion or pulling sensation is elicited. In this paper, we applied this phenomenon to the sole (plantar surface of the foot) to present the sensation of ground slope.

Rate of Hanger Reflex Occurrence: Unexpected Head Rotation on Fronto-temporal Head Compression.

When the head is encircled with a wire clothes hanger and the unilateral fronto-temporal region is compressed, the head rotates unexpectedly. As the mechanism is unclear, however, we have temporarily named this phenomenon as the "hanger reflex." We previously reported a case wherein this phenomenon was applied to treat cervical dystonia.

Tactile motion aftereffects produced by appropriate presentation for mechanoreceptors.

Tactile motion perception is one of the most important functions for realizing a delicate appreciation of the tactile world. To explore the neural dynamics of motion processing in the brain, the motion adaptation phenomenon can be a useful probe. Tactile motion aftereffects (MAE), however, have not been reported in a reproducible fashion, and the indistinctive outcomes of the previous studies can be ascribed to the non-optimal choice of adapting and testing stimuli.

Development of anthropomorphic multi-D.O.F. master-slave arm for mutual telexistence.

We developed a robotic arm for a master-slave system to support "mutual telexistence," which realizes remote dexterous manipulation tasks and close physical communication with other people using gestures. In this paper, we describe the specifications of the experimental setup of the master-slave arm to demonstrate the feasibility of the mutual telexistence concept. We developed the master arm of a telexistence robot for interpersonal communication.

Reaction of carbonyl compounds with trialkylsilyl phenylselenide and tributylstannyl hydride under radical conditions.

A novel method for the hydrosilylation of carbonyl compounds has been developed. When carbonyl compounds were allowed to react with trimethylsilyl phenylselenide and tributylstannyl hydride in the presence of a catalytic amount of AIBN as the radical initiator, hydrosilylation of the carbonyl compounds efficiently proceeded to give the corresponding silyl ethers in moderate to good yields. In the absence of carbonyl compounds, the triethylsilyl hydride was obtained by the reaction of PhSeSiEt(3) with Bu(3)SnH.