Tota Mizuno

Computer Input System Using Eye Glances

We have developed a real-time Eye Glance input interface using a Web camera to capture eye gaze inputs. In previous studies, an eye control input interface was developed using an electro-oculograph (EOG) amplified by AC coupling. Our proposed Eye Gesture input interface used a combination of eye movements and did not require the restriction of head movement, unlike conventional eye gaze input methods. However, this method required an input start operation before capturing could commence. This led us to propose the Eye Glance input method that uses a combination of contradirectional eye movements as inputs and avoids the need for start operations. This method required the use of electrodes, which were uncomfortable to attach. The interface was therefore changed to a camera that used facial pictures to record eye movements to realize an improved noncontact and low-restraint interface. The Eye Glance input method measures the directional movement and time required by the eye to move a specified distance using optical flow with OpenCV from Intel. In this study, we analyzed the waveform obtained from eye movements using a purpose-built detection algorithm. In addition, we examined the reasons for detecting a waveform when eye movements failed.

Color influences on human beings evaluated by nasal skin temperature

Since colors affect human beings both physiologically and mentally, various studies have been conducted about the infl uences of color. Most of the studies have been focused on the psychological aspects. In this study, we investigated the infl uences of color physiologically by the use of infrared thermography. With this technique, the subjects wear no devices, and objective values are expected to be obtained to evaluate the infl uences of color. Nasal skin temperatures were measured by infrared thermography under yellow, red, and blue illuminations. A significant temperature change was observed under red illumination.

Driver's drowsiness inhibition by subcutaneous stimulation based on SNS activity

The overall aim of the study is to develop the ambient drowsiness control programs based on driver’s physiological states. this study is developed and verified of a system that controls a driver’s drowsiness a stimulus that is too small to be noticed by a driver. Most studies on driver drowsiness have focused on the detection or evaluation of psychological states in some way. Our system assumes that a small change in temperature affects peripheral thermoreceptors and that afferent fibers transmit this stimulus to the cerebral center via the spinal nerves. To evaluate the system, we constructed a virtual reality system for automobile driving using an experimental method described in our previous studies. In this study, drowsiness was controlled by our system, and the effectiveness of the system was tested. The results suggest that this is an efficient method for controlling driver drowsiness.

Analysis of 1/f fluctuation of keystroke dynamics and heart rate variability

Mental stress has been an issue in modern society. Several studies have investigated the detection of mental stress using physiological indices. However, measurement of these indices would itself impart a certain level of stress to subjects. The temporal dynamics of key typing are called “keystroke dynamics”. Keystroke dynamics show variations with psychological subtlety. The objective of this study was to develop a technique for ambient, unconscious measurement of mental stress based on keystroke dynamics. The relationship between fluctuations in keystroke dynamics and cardiac activity, in the form of heart rate variability, was analyzed. Intervals between key strokes were measured while using a computer under conditions of auditory stimulus or cognitive stress was determined. Power exponent β of the regression curve of the power spectrum for the time series of inter-stroke time (IST), and the power spectrum density of the high-frequency component (HF) for the time series of the R-R interval extracted from electrocardiography were calculated. As a result, the power spectrum of IST approached 1/f with auditory stimulus or cognitive stress, and a significant correlation existed between β and HF.

Study of eye-glance input interface

Optical measurement devices for eye movements are generally expensive and it is often necessary to restrict user head movements when various eye-gaze input interfaces are used. Previously, we proposed a novel eye-gesture input interface that utilized electrooculography amplified via an AC coupling that does not require a head mounted display[1]. Instead, combinations of eye-gaze displacement direction were used as the selection criteria. When used, this interface showed a success rate approximately 97.2%, but it was necessary for the user to declare his or her intention to perform an eye gesture by blinking or pressing an enter key. In this paper, we propose a novel eye-glance input interface that can consistently recognize glance behavior without a prior declaration, and provide a decision algorithm that we believe is suitable for eye-glance input interfaces such as small smartphone screens. In experiments using our improved eye-glance input interface, we achieved a detection rate of approximately 93% and a direction determination success rate of approximately 79.3%. A smartphone screen design for use with the eye-glance input interface is also proposed.

Physiological and Psychological Evaluation by Skin Potential Activity Measurement Using Steering Wheel While Driving

This paper proposes a new method for practical skin potential activity (SPA) measurement while driving a car by installing electrodes on the outer periphery of the steering wheel. Evaluating the psychophysiological state of the driver while driving is important for accident prevention. We investigated whether the physiological and psychological state of the driver can be evaluated by measuring SPA while driving. Therefore, we have devised a way to measure SPA measurement by installing electrodes in a handle. Electrodes are made of tin foil and are placed along the outer periphery of the wheel considering that their position while driving is not fixed. The potential difference is increased by changing the impedance through changing the width of electrodes. Moreover we try to experiment using this environment. An experiment to investigate the possibility of measuring SPA using the conventional and the proposed methods were conducted with five healthy adult males. A physical stimulus was applied to the forearm of the subjects. It was found that the proposed method could measure SPA, even though the result was slightly smaller than that of the conventional method of affixing electrodes directly on hands.

Development of a Glasses-Like Wearable Device to Measure Nasal Skin Temperature

Since nasal skin temperature is said to provide a good reflection of autonomic nerve activity, nasal skin temperature measurements have been used to assess various human physiological and psychological states, such as pleasant and unpleasant emotions, alertness levels, and mental work load (MWL). In addition, nasal skin temperature has the advantage of enabling non-contact measurement, using such as thermography and radiation thermometers.However, a problem exists with approaches using these device because it is difficult to make accurate assessments if the test subject moves during measurement.

Autonomous reconfiguration of robot shape by using Q-learning

A modular robot can be built with a shape and function that matches the working environment. We developed a four-arm modular robot system which can be configured in a planar structure. A learning mechanism is incorporated in each module constituting the robot. We aim to control the overall shape of the robot by an accumulation of the autonomous actions resulting from the individual learning functions. Considering that the overall shape of a modular robot depends on the learning conditions in each module, this control method can be treated as a dispersion control learning method. The learning object is cooperative motion between adjacent modules. The learning process proceeds based on Q-learning by trial and error. We confirmed the effectiveness of the proposed technique by computer simulation.

Discrimination of Eye Blinks and Eye Movements as Features for Image Analysis of the Around Ocular Region for Use as an Input Interface

This paper examines an input method for ocular analysis that incorporates eye-motion and eye-blink features to enable an eye-controlled input interface that functions independent of gaze-position measurement. This was achieved by analyzing the visible light in images captured without using special equipment. We propose applying two methods. One method detects eye motions using optical flow. The other method classifies voluntary eye blinks. The experimental evaluations assessed both identification algorithms simultaneously. Both algorithms were also examined for applicability in an input interface. The results have been consolidated and evaluated. This paper concludes by considering of the future of this topic.

Estimating autonomic nerve activity using variance of thermal face images

In this paper, we propose a novel method for evaluating mental workload (MWL) using variances in facial temperature. Moreover, our method aims to evaluate autonomic nerve activity using single facial thermal imaging. The autonomic nervous system is active under MWL. In previous studies, temperature differences between the nasal and forehead portions of the face were used in MWL evaluation and estimation. Hence, nasal skin temperature (NST) is said to be a reliable indicator of autonomic nerve activity. In addition, autonomic nerve activity has little effect on forehead temperature; thus, temperature differences between the nasal and forehead portions of the face have also been demonstrated to be a good indicator of autonomic nerve activity (along with other physiological indicators such as EEG and heart rate). However, these approaches have not considered temperature changes in other parts of the face. Thus, we propose novel method using variances in temperature for the entire face. Our proposed method enables capture of other parts of the face for temperature monitoring, thereby increasing evaluation and estimation accuracy at higher sensitivity levels than conventional methods. Finally, we also examined whether further high-precision evaluation and estimation was feasible. Our results proved that our proposed method is a highly accurate evaluation method compared with results obtained in previous studies using NST.