The twentieth century was what we call a machine-centered century. The twenty-first century is a human-centered century in every respect, with scientific technologies that are friendly to humans and the natural and social environments of humans being valued. Therefore, research, development, and deployment of advanced scientific technologies may no longer be determined solely by technological communities, and issues whose solutions have been carried over to the twenty-first century may not be solved by the technologies of only one specific field. For example, tie-ups and cooperation with human and social scientists are greatly needed, since the issues can no longer be solved by the scientific efforts of research and development alone. It is no exaggeration to say that such issues today affect all aspects of social technologies. Therefore, these issues can no longer be solved by conventional solutions. Matured technologies that have brought happiness to humans are among interdisciplinary scientific areas, and the mounting issues to be solved in the twenty-first century cannot be fully understood by conventional technological frameworks; the nature of scientific technology issues that we need to understand is obviously changing. Research focused on Kansei is expected to be the solution to these issues with the greatest potential. Meanwhile, it is only recently that interest in Kansei values has rapidly heightened as the Ministry of Economy, Trade and Industry launched the "Kansei Value Creation Initiative." However, it is true that we have many issues to solve including the development of new viewpoints in defining the universal characteristics of Kansei values, detailed guidelines for future research, etc. Kansei engineering originally evolved as a way to "introduce human 'Kansei' into manufacturing." The recent trend indicates that the development of Kansei engineering is expanding beyond manufacture and design and is widening into relevant fields, creating one of the most conspicuous features of Kansei engineering. This trend can also be felt by presentations made at the recent annual conferences of the Japan Society of Kansei Engineering. It is needless to say, therefore, that some kind of interdisciplinary development is necessary to find a mechanism for creating Kansei values, which is as important as the Kansei values themselves. The first part of this paper describes the general history of Kansei and the basic stance and concept of Kansei research. The second discusses the significance and roles of creating Kansei values in Kansei engineering and also provides basic ideas that will serve as future guidelines, with its positioning in mind debating from many aspects. The third part of this paper shows that the concept of Kansei/Affective value creation is an essential tool for the decision making, for example, in the field of marketing. It is shown that the Kansei/Affective information provides an important role for the decision making. Some illustrative examples are shown to demonstrate the effect of Kansei information. And, finally, the paper will provide a summary of KEER2010 held in Paris in March 2010 to describe the world trend of Kansei engineering research.

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"Iyashi" is a term that everyone often hears of in Japan. When people get depressed or feel down, they usually want "Iyashi" so as to gain satisfied or peaceful mind. However, in consideration of the various usage and different meanings of Iyashi in the past, what and how feeling or mood, obtained from the various Iyashi methods, affects to the minds? In this report, the effect of Iyashi to the peoples' minds are analyzed, and the relationship between the means of Iyashi and the effects to the minds will be discussed for the possible application in the engineering fields.

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In soccer, the knuckling shot is a kicking technique in which no or slight rotations are applied to the ball, thereby making it move irregularly. However, the technical characteristics of knuckling shots are still unclear, and considerable analysis is required. In this study, we have investigated the swing characteristics of the kicking leg and analyzed the impact process of the kicking foot in order to elucidate the technical characteristics of the knuckling shot. The tendency to impact with the heel pushed out towards the inside of the foot was considered. The angle of attack in the knuckling shot (4°) was smaller than those in the straight and curve shots (20° and 33°, respectively) and was believed to be a factor for balls with smaller rotational frequencies. As a result, in the knuckling shot, reduced angles of attack between the face and swing vectors at impact surfaces and the primarily translational motions at ball impacts are fundamental and important characteristics.

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The configuration of soccer balls has closely approached a perfect round shape by not only reducing a number of panels but also by eliminating roughness of the panel joints by thermal bonding process recently. Therefore, in a non-rotating or low-rotating moving shot, a soccer ball drops and curves by the change of wake flow, which is called a knuckle ball effect. It is said that the cause of the swerving ball on no rotating shoot of the soccer ball depends on the outbreak of the vortex occurred in the wake. However, it is not grasped the timing among the vortex outbreak and the swerving of balls. In this study, the velocity fluctuation of the ball wake was measured with hot wire probe and the oscillation of the ball was measured with three components load cell. And also the asymmetric configuration of the ball panel against moving direction was investigated as a factor to bring unexpected change of the ball orbit. The results show that the position change of the tail of vortex ring affects the swerving of the balls and that the low-rotating ball changes its face against the moving direction and it produces irregular lateral force.

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Accurate method to measure aerodynamic force on spinning soccer ball is studied. To get smooth rotation of soccer ball in wind tunnel flow, rotation shaft was inserted in the ball after filled with a foaming urethane agent, to keep sphere shape of the ball. Static balance around rotation shaft is hold kept using some weight balances. But, dynamic balance around this shaft is not enough to continue wind tunnel experiment for aerodynamic force measurement.

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With tunnel experiments for aerodynamic force of spinning baseball ball are conducted for various direction of spinning axes. The characteristic side force results in opposite direction by seam arrangements, which we call 2-seam or 4-seam balls.

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For the understanding of a pitched baseball trajectory, flight angle, spin rate, and spin axis are very important factors which are desired to measure exactly. In a measurement of the baseball spin using a high speed video camera, it is difficult to evaluate exactly through an automated image processing, because of the extremely poor quality of a ball image captured in the outdoors. In order to correct the erroneous results obtained through the automated image processing, a smoothing spline technique is introduced. From the derivatives of the smoothed ball Eulerian angles, an accurate ball spin vector (i.e. spin rate and spin axis) is attained. For the sake of the verification of the automated image processing result, an application program which supports to perform the manual image processing easily and exactly has been developed. Concerning an analysis of the spin vector for pitched baseball images, automated and manual image processing results coincide considerably with each other.

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In this paper, we constructed a motion measurement system using the triaxial gyro and acceleration sensor as a means of measuring the motion. The pitching form and the ball initial rate at the baseball were measured by using this system.Next,the relation between measured motion parameters and ball initial rate was examined. As a result, we found that there are significant differences in the movement of the upper limb between experienced and inexperienced person. The parameters that affect improvement of the ball initial rate were extracted !) in the experienced group and 4 in the inexperienced group.

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The aim of this study was to investigate the trade-off relation between the speed and accuracy of a pitched baseball. To do this, the initial velocity of the ball at release and the distance between the arrival position of pitched ball and the target were measured at the four different subjective effort levels. Three baseball pitchers each performed 2 sets of 6 pitches at subjective effort levels of 100%, 90%, 70%, and 50%; in each of the sets, the target was set at a different height above home plate. Each pitcher threw 48 pitches in total. The pitching motion and trajectory of the ball were videotaped with a high-speed video camera and normal video camera, respectively, and analyzed by three-dimensional direct linear transformation. The following results were obtained. Although there were individual differences between participants, the initial velocity of each pitched ball at subjective effort levels of 100%, 90%, and 70% was over 90% of the participant's maximum velocity, and in general, the accuracy of the pitch and initial velocity of the ball at release had a trade-off relation: accuracy increased with decreasing initial velocity. However, at the 50% subjective effort level, the opposite relation was observed: accuracy decreased with decreasing initial velocity. As the subjective effort level was reduced, all the participants changed their pitching motion at a certain subjective effort level. This change in pitching motion possibly caused the pitchers to change their technique for releasing the ball, and consequently the trade-off relation no longer held.

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We propose an effective non-contact and non-attached technique for detecting sports motion by measuring the current, which is approximately of the order of sub-picoamperes, generated because of a change in the capacitance between a given electrode and the human body. A theoretical model is proposed for the electrostatic induction current generated because of a change in the electric potential of the subject's body due to foot motions. We apply the proposed technique to determine the time for which an athlete's foot remains in contact with the ground and off the ground during pitching and batting motions while playing baseball. Thus, we can quantitatively estimate the time for which an athlete's foot is in contact with the ground and off the ground on the basis of the time at which peaks were observed in the waveforms of the electrostatic induction current.

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A shuttlecock which has an open conical shape is a high-drag projectile used in the sport of badminton, and the shape of the shuttlecock makes it aerodynamically stable. In the present study, measurements of aerodynamic forces and flow visualization experiments are carried out in order to investigate the relationship between fluid forces and vortex behavior around a shuttlecock at high Reynolds numbers. And the effect of shuttlecock deformation on aerodynamic properties was also investigated because it is presumed that aerodynamic forces are affected by the deformation of shuttlecock skirt. The drag coefficient for the shuttlecock with no gap is significantly smaller than that for the ordinary shuttlecock (with gap). For the ordinary shuttlecock, the air flows through the gap in the shuttlecock skirt, and this flow is related to high aerodynamic drag.

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We performed wind-tunnel experiments with two Archery arrows (X10, A/C/E) without mechanical support on JAXA's Magnetic Suspension & Balance System. We measured the relation between Reynolds number and drag coefficient, as well as we checked the relation between drag coefficient, lift coefficient and pitching-moment coefficient with the angle of attack. We found that the vanes impose a lift force and increase the orientational stability. In the available range of Reynolds (0.3 × 10^4 < Re < 2.5 × 10^), the boundary layer on the arrow shaft remained laminar. We compared these results with experiments of arrows in free flight which we recorded with two high-speed video cameras. We also compared the results of XlO's aerodynamic propertie with A/C/E's.

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Four components load cell by air suspension method is developed. 20 time's sensitive sensor and mirror for reflection of sensor infrared rays made good improvements for linearity and resolution. Calibration result with this interference toward another direction was obtained. Performance check of this load cell was conducted for aerodynamic characteristics of high speed spinning golf ball in the wind tunnel flow.

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Shuttlecock used in a badminton match is light mass, which is strongly influenced by air resistance and the wing of the skirt can be easily broken. The highest initial velocity of the shuttlecock exceeds 300km/hr for a professional badminton player. In this study, new insertion equipment and the motion control system were proposed, and an exercise machine for badminton, used to project the shuttlecock at high speeds (over 42m/s), has been developed. The mechanism of the shuttlecock launcher in this machine was achieved using the friction force between two turn rollers and the shuttlecock. The results of the launcher experiments using the badminton machine show that the machine can project the feather shuttlecock at the maximum flight distance of about 11.5m, with a standard error of about 0.32m and the highest initial speeds being 52.8m/s. In addition, the launcher performance of the badminton machine was improved by having produced the launching device which supplied many shuttlecocks continually.

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We are developing a system to confirm 3-D coordinate (X(t), Y(t), Z(t)) of golf ball flight trajectory by using video camera image. Information of tilt θ(t) and pan φ(t) angles of the camera are detected by two rotary encoder. The absolute distance r(t) from the camera to a golf ball will be detected in relation to the number of pixel area of a golf ball on the screen. Zooming mechanism is included in this system and some trials were conducted to include zooming mechanism.

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This paper proposes a measuring device that uses carrier phase positioning GPS and accelerometers for pitch and stride measurement of athletes. In this system, Synchronize the timing of the ground contact measured by accelerometer and position information measured by GPS to measure the pitch and stride. In this paper, System summary and method of detecting contact with the ground using the accelerometer. And measurement principles of carrier phase positioning GPS and experiments that evaluate the precision and accuracy of carrier phase positioning GPS. Matching of position data and ground contact data, pitch and stride measurement using this system are described.

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This paper deals with the motion analysis of skiing turn using joint angle and gliding velocity of skier. The joint angle is calculated from the 3D orientation estimated using the information of the orientation measurement system. The gliding velocity is estimated from GPS receiver output, accelerometer output and 3D orientation. The measurement experiment has conducted by skier attached the measurement systems. The hip joint angle and the gliding velocity of skidding turn and carving turn have estimated by sensor fusion. The joint angle and the gliding velocity have indicated the difference motion on these turns. Furthermore, the motion analysis using both the joint angle and the gliding velocity has indicated the motion timing at switchover and change of turns. The result of motion analysis using the joint angle and the gliding velocity has obtained more major features than the results of motion analysis using each one. The proposed motion analysis method can be used to evaluate quantitatively the skill.

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The acceleration in the loading motorcycle steering wheel on non-pavement road was measured. The maximum acceleration increases from 85m/s^2 to 142 m/s^2 when the running speed increases from 10 to 20 km/h, and the average acceleration has increased from 13.2 m/s^2 to 26.1 m/s^2 similarly, too. The maximum acceleration has decreased from 131 m/s^2 to 52 m/s^2 when the tire inflation pressure of the loading motorcycle is decreased from 950kPa to 200kPa. Moreover, the average acceleration has decreased from 24.6 m/s^2 to 12.4 m/s^2, too. The number of cyclocross tires has decreased from 125 m/s^2 to 57.5 m/s when the tire inflation pressure is decreased from 600kPa to 200kPa The maximum acceleration decreased decreasing in the result tire air pressure that did the front wheel fall test from 120mm in height, and a tendency almost similar to the real run test was shown. When the cyclocross frame made of CFRP was used, both maximum accelerations and the average accelerations indicated a high value from the steel frame. As for the maximum acceleration, it decreases, and it has been understood to decrease from the loading motorcycle running in 20 km/h running on non-pavement road, installing the tire for the cyclocross in the cyclo made of CFRP crossing frame compared with, and adjusting the tire inflation pressure to 200kPa 15.1 m/s^2 of 40% decrease in average acceleration of the former 1/3 of the former 43.4 m/s^2.

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BACKGROUND: In previous biomechanics studies on triple Jump, constructed by hop, step and jump, have not revealed the joint power in lower limb in these three jumps at a time. The purpose of the present study was to clarify the characteristics of joint power of the three lower limb in support period. METHODS' Subjects were six male athletes triple jumpers. They tried triple jump with maximal effort outdoor, and their jumping motions were videotaped using 3D motion capture device (200Hz). RESULT: The joint power output in the lower limb has showed a common pattern in the support phases in three jumps. The work in knee joint was especially more negative than that in other joints. It was suggested that eccentric contractions in each of the support period. There was no significant correlation relationship between touchdown angle and work in step and jump phase.

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The purpose of this study is to investigate the effect on jumping motion in changing takeoff-angle. The subjects were two male university students (23yrs, 179.0cm, 74.8kg and 21yrs, 169.3cm, 66kg). They performed vertical jump and three kinds of takeoff-angle standing long jumps on a force platform. The motion is simultaneously recorded by a High speed camera (125fps). The results are as follows. The ankle joint angle is same in jumping motion between both subjects and every different takeoff-angle. The knee joint angle is different between subjects. Subject A changed the max flexion time in jumping motion, but subject B didn't change. As the subject jump lower, the knee joint torque is smaller, and the hip joint torque is larger. To change takeoff-angle, Subject A adjusts the timing of joint flexion, but subject B adjusts the different way from subject A.

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Recent years have seen a worldwide increase in people participating in Nordic walking (NW). This trend has led to abundant research in NW. A high exercise effect for NW is recognized now. However, there are few studies focused on the various joint loads for NW. The purpose of this study is to compare the joint load for NW to ordinary walking (OW) on a level ground and for going up and down stairs. 3D inverse dynamics was used to calculate joint reaction force and joint moment. Then, the joint forces (compression and shear) at each of the lumbar spine, hip, knee and ankle joints were calculated using the Software for Interactive Musculoskeletal Modeling (SIMM). It was found that NW reduces the load of the lumbar spine and lower limb joints compared with OW on a level ground and going up stairs, but not going down stairs.

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This paper describes the relation between the motion of the human lower leg and force applied to the knee joint using the dynamic model of a human lower leg. The dynamic model was built using links, joints, and a muscle model. The muscle model consists of a contractile element, an elastic element, and a viscous element. The dynamic model was validated through the comparison of the simulated and experimental results. The force applied to the knee joint was investigated with changing the angle of the knee joint and the contraction length and time of the contractile element in the simulations. The simulated results demonstrated that the bending of the knee joint for shock relaxation not only decreased the vertical force applied to the knee joint but also increased the horizontal force. This fact suggests that the bending of the knee may cause the cruciate ligament injury. The simulated results of actively controlling the contractile element indicated that both forces could be reduced by choosing the appropriate combination of contraction length and time.

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The purpose of this study was to investigate the effect on back load during lifting movement by varying lower limb and trunk posture. Seven subjects performed lifting movements with four conditions, using two foot positions (Odeg, 60deg), and two trunk postures (Neutral, Stoop). 3D kinematics and kinetics data were recorded. Significant decreases in peak right bending angle at L4/L5 and T9/T10 joint were found when subjects rotate right hip joint externally. Stoop posture decreases peak joint reaction force for pelvis longitudinal axis but increases peak left bending toque. To perform lifting movement safely, it is recommended that you rotate hip joint externally and keep trunk neutrally.

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The purposes of this study were to investigate effects of conditions on knee joint load during cutting movement, and to compare them during experiment, and to examine what condition pose a risk for knee injury. Three experiments were performed by 6 male graduate students: control, slow and fast speed, 45 degree direction, toe in and toe out cutting .Knee joint forces and moments were calculated by Inverse dynamics. During fast speed, peak posterior force was greater than low speed. During toe-out, peak abduction moment was lower than toe-out and control cutting. It was suggested that in toe out cutting, the risk of knee injury is decreased by greater peak abduction moment with comparison of toe in and control cutting.

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The purpose of this study was to examine the relationship between the position of COG and response time on 3 experiment conditions setting right, center and left position of COG with flexing 60 degree angle at hip and knee joint. Six subjects kept the assigned posture on a forceplate until LED signal. After the signal, each subject moved to left or right as quickly as possible. RESPONCE TIME was defined as the interval time from the LEDsignal to kick-foot off (kick-foot was the opposite leg from movement direction). MOVEMENT TIME was defined as the interval time from the LED signal to the time that COG shifted 40% of height form the midpoint of initial second metatarsal in the lateral direction. In the result, MOVEMENTTIME were shortened on condition that COG shifted the position for movement direction.

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Many players can have a huge amount of bewildering information for golf swings by golf magazines and books. However, there is no particular swing for each club. The purpose of this study was to understand characteristic of golf swing using three different clubs: driver, five-iron, and nine-iron. Two right-handed female professional golfers used their own clubs to hit standard golf balls in our laboratory. The swing motions were recorded using a 3D optical motion capturing system with 250Hz frame rate. The results showed that there was a similar timing between the three clubs tested, but kinematics and the club head speed were different depending on the three different clubs used. However, the maximum acceleration of club head appeared at same time, and tendencies of hip rotation until just before impact were similar.

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The purpose of this study was to investigate the characteristics of the golf swing motion associated with the club head acceleration in driver shot. The subjects were 8 female professional golfers and they performed 10 shots with own driver in a laboratory. During the performing the driver shot, 3D coordinates of body and club landmarks were obtained using the motion capture system with operating at 250 fps. We found that the energy in the club head was mainly consisted of the transitional kinetic energy, and the effect of the rotational kinetic energy and potential energy were small. The maximal value of the changing rate of head speed and left wrist speed was significantly greater in professional group (p<0.01). In professional group, the speed of wrist, elbow, and shoulder decreased rapidly after achieving a peak. It was suggested that the head speed could be accelerated by decelerating joint speed in impact.

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We proposed wireless sensor monitoring system of club velocity and attitude during a golf swing. Club attitude and shaft head velocity during golf swing are calculated from wireless sensor system including accelerometers and gyroscopes. To estimate the precision of parameters from sensor system, the same parameters are calculated from motion capture system (VICON). Additionally, we also evaluated azimuth of shaft head velocity and angular velocity defined by cross product of club long axis and shaft head velocity.

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Backhand drive in table tennis is getting more important in recent years because the rally is becoming speedy. Its coaching method, however, has yet to be established due to the lack of basis motion data. In order to obtain kinematic features in backhand drive for evidence-based coaching, we compared four different backhand-drive motions with an emphasis on speed or control and with top or back spins of the ball. Experiments using five experienced table-tennis players and an optical motion capture system revealed that the angular velocity of the elbow supination and extension should be increased in case of speed emphasis, and the elbow joint valgus would be necessary in case of backspin ball, demonstrating the importance of the elbow joint motion in backhand drive.

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The purpose of this study was to investigate the relationship between angular velocity of the bat and movements of upper limbs. Nine hitters performed free-batting practice. An electromagnetic tracking device was used to record three dimensional kinematic data of the thorax, the humerus and the forearm of the both side and the bat. The results showed that sequential rotation, in order of the thorax, the shoulder, the elbow and forearm, was observed on the lead arm for all subjects. All joint range of motion on the push arm were larger than that on the lead arm. There was a significant correlation between swing angular velocity and shoulder range of motion for horizontal abduction on the lead arm. No correlation was founded between the rolling angular velocity and body movements, indicating that the magunitude of the rolling angular velocity is not associated with the range of each joint motion and the timing of sequential action.

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The purpose of this study was to clarify the kinetic role of the upper limbs under conditions of different hitting-point heights in the baseball T-batting motion through inverse kinetic analysis. Twenty-three collegiate male baseball players' motion were captured with VICON MX system (12-camera, 250Hz), and kinetic data at each hand were collected by using an instrumented bat equipped with 28 strain gauges (lOOOHz). Three heights of hitting point (high, middle, low) were set according to the baseball rules. The joint torques and works of the upper limbs were divided into the values caused by horizontal and vertical component offerees exerted on the bat by each hand. The results show that (1) the hitting point motion of bat were modified mainly with translational movement of the bat, and a significant difference occurs in the forces of each hand in the vertical direction under the height conditions, (2) the barrel side upper limb contributes to adjust the bat height from the analysis of joint torques caused by horizontal component of bat force, (3) shoulder joints are great contributors to adjust the bat height in the down swing phase from the analysis of joint torques caused by vertical component of bat forces, and (4) the role of elbow joint of the barrel-side upper limb is to control the bat head movement because the work done by the joint was negative values.

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The purpose of this study was to investigate the effectiveness of the torso and upper extremity rotation for producing the bat-swing velocity in baseball batting. Seventeen male collegiate baseball players were asked to perform the batting trials using a batting-tee. Three-dimensional kinematic data were recorded by an optical motion capture system operating at 500Hz. The rigid link model consisting of five segments (pelvis, thorax, shoulder girdle, upper extremity and bat) developed to calculate the contribution of the torso and upper extremity rotation to producing the bat-swing velocity. In the early swing phase, the contribution of the pelvic rotation around the vertical axis was larger than the rotation of other segments. In the late swing phase, the contribution of the rotation of the upper extremity relative to the shoulder girdle and the bat relative to the upper extremity around the vertical axis were large.

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The hockey sticks have been developed under traditional and empirical ways. Nowadays players must take a low stance to hit a ball strongly because the sweet spot of the conventional stick locates about 180mm apart from the tip. The purpose of this study is to develop a new hockey stick considering the players' motion. We found that the mass distribution of the stick affects on the position of the sweet spot. Owing to this knowledge we designed a new shape stick that had the sweet spot rather near tip. A newly designed stick and a conventional shape stick were made of wood to be compared each other. It is also revealed that the new stick is very easy to handle on ball keeping and other handling motions.

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It is important to find an aortic aneurysm in early stage. Imaging examinations can find the aortic aneurysm, however they are not used for screening because of high cost. On the other hand, pulse wave can be measured easily. The aim of this study is to propose an easy method to find the aortic aneurysm using pulse wave. The basic theory is based on the wave of reactance silencer. The relation between the pressure transfer function of pulse wave and the expansion of artery was formulated. The computer simulation model of whole human artery was constructed. The transmission loss of pulse wave is increased by increase of the inner radius of aortic aneurysm. The frequency interval of local minimum values of the transmission function is decreased by increase of the length of aortic aneurysm or decrease of the Young's modulus. The method to find the aortic aneurysm from the pressure transfer function between brachial and anterior tibial arteries was investigated theoretically. This method can be used for diagnosis of aortic aneurysm.

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Blood pressure monitoring in daily life is important from a perspective of lifestyle-related diseases prevention. Conventional ambulatory blood pressure monitoring (ABPM) device can measure blood pressure at regular interval for 24 hours. However, it is limited by long measuring time, low sampling rate, and constrained posture. We developed a wearable sensor for monitoring a continuous blood pressure using the pulse wave velocity method. Results of exercise test by an ergometer show its effectiveness. A mobile software in a smart phone is in charge of controlling data acquisition, displaying general information and signals for real-time monitoring, and sending data to the database server. In this paper, we report sensor development and discuss pilot study results in a hospital.

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It proposed the index value of the open Cho rate and the open Cho angle where the spread foot is simply judged without using X rays, and the relation to other diseases is investigated. As a result on subjects, 37% or more in open, 15 degrees or more reached the index value, and the pain by hallux valgus and the pain of the second metatarsal bone were often the cases in open. It seems to be necessary that some treatment with in-sole are required at the early stage to prevent from the injury if the decrease of horizontal arch is found.

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Sleep is necessary for human health and acttivities. Recently, the sleep problems have become matters of public concern. There is a report that 20 percent of Japanese people have sleep problems. Therefore, the topic of sleep problems have been taken up by the media and increased the number of topics about bedding and bedroom. In particular, pillow have received much attention of many people. The clinical reports showed that pillow is one of the factor for sleep problems. And this report says that sleep problems are related to the height of the pillow. However, there is little for engineering approach about sleep problems and pillow. In this study, stress distribution analysis was done for clarifying mechanical relation of the pillow and cervical vertebrae on spine position. The experiment used 2 dimensional and 3 dimensional photoelastic method. Specimen model was prepared by reference to clinical report. The experimental results shows that concentration notably appeared near the first and sixth cervical vertebrae.

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The purpose of this study is to develop a 3D kinematic model of the index finger for estimating the flexion and extension movements. High-resolution MRI scans were used in conjunction with CAD software to determine the three-dimensional moment arms for the muscles and tendons passing the interphalangeal and metacarpophalangeal joints of the index finger. The moment arms for each tendon or muscle were expressed with reference to the joint center. The results were presented at five or six different postures of the index finger. The results were presented for five or six different angles of joint flexion for a single tendon or muscle. The moment arms of tendons at the MP joint had results similar to those presented by An et al. or Fowler. Muscles at the MP joint had moment arms deviating from those presented by An et al. or Fowler.

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The purpose of this study is to investigate the functional posture of the index finger with the surface EMG (electromyography) in order to define the rest state of the index finger. The variation of EMG responses of muscles driving the index finger actions was statically or dynamically measured at some postures of the index finger. The three finger postures were defined in the experiment. Whether the functional posture of the index finger can be determined with the variation of surface EMG of muscles of the index finger was investigated. It was suggested that it is possible to distinguish the functional posture of the index finger with the surface EMG of two or more muscles statically.

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Prediction of injured body regions and injury severity from available accident data can lead to more appropriate and hastier emergency care for traffic accident casualties. The objective of this study was to develop a method to obtain the injury prediction equations by utilizing accident database consisting of numerous computer simulation results. Vehicle acceleration waveforms in frontal collision accidents were estimated using vehicle characteristics based on statistical analysis of full-wrap frontal collision test results in JNCAP and NHTSA. The estimated vehicle acceleration waveforms were found to be valid by comparing the injury value time responses and the movement of the occupant with those obtained in JNCAP.

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To evaluate the dynamic behavior of human body at landing, a link model, a musculoskeletal model or multi-degrees-of-freedom model are generally used. In this study, the relation of these models is investigated. The movements of the reference points on the body and the floor reaction force were measured at landing. A four-degrees-of-freedom (4-dof) model is constructed and the parameters are identified such as to reconstruct the measured reaction force. And a four-link (4-link) model is also constructed and the joint forces and the moments are obtained by the inverse dynamics. It was shown that the joint reaction force from the 4-dof model and the vertical component of the joint reaction force from 4-link model agreed well. The joint reaction force from the link model is constructed by the joint forces and the muscle forces, so that the joint reaction force from the M-dof model can evaluate the joint force and the muscle force.

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We examined the stress distribution occurring in a two-dimensional sagittal gelatin model using optical stress analysis to make clear the mechanism of the intracranial damage in the shaken baby syndrome (SBS). We modified Holbourn's model and added the lateral ventricle. The device consisted of rotation table, green light source, polarizer, gelatin model and high-speed polarized camera. The model oscillated rotationally in the sagittal direction with 60 degrees of central angle and 2-3Hz of frequency. The average peak values of linear acceleration, angular velocity and acceleration in flexion were 1.7G, 3.5rad/sec and 183.4rad/sec^2, respectively. In color image sequence for major polarization axis direction indicating stress generations, color changes occurred clearly in frontoparietal region near by brain surface just before full flexion. We consider the results may be important for explaining the mechanism of brain injuries in the SBS such as subdural hemorrhage or brain damage.

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Recently, the improvement of ride comfort is essential for vehicle designs to add commodity value. A technique to well predict the ride comfort for vehicle passengers is strongly required from the above viewpoint. Vibration comfort such as fatigue and motion sickness are essential elements of ride comfort. It is known experimentally that the ride comfort is influenced by dynamic characteristics of the passenger in the lateral and roll direction at low-frequencies. This paper investigates the modeling of a seated human body by MBD approach for the basis of comfort evaluation. For that, we aim to reproduce the response of the human body in the lateral and roll direction simultaneously.

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This paper describes sheep's head voxel model from CT and MRI images. Hard tissue such as skull was represented from CT images, soft tissue such as brain was represented from MRI images. The sheep model consist of nine hundred thousand voxels holistically.

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