Satoshi Yoshinari

Hokkaido Research Organization | HRO

For the evaluation of the usability and the physical burden of using products, average values of various biological information such as muscle activity measured by electromyogram (EMG) or energy metabolic rate are estimated. However, the force to be applied to a products and the posture are sometimes different because of difference of individuals a...

Manual handling is one of the factors that increase the risk of upper limb disorders. Especially, most of workers in Japanese primary industries still do such operations in high risk. The purpose of this study is to reduce upper limb burden during manual handling in primary industries. We performed work observation and simulated work experiment wit...

Electromyography computed tomography (EMG-CT) method is proposed for visualizing the individual muscle activities in the human forearm. An EMG conduction model was formulated for reverse-estimation of muscle activities using EMG signals obtained with multi surface electrodes. The optimization process was calculated using sequential quadratic progra...

This paper describes an innovative passive element for assistive device and its application. S-FRP is an elastic composite consisting of FRP and rubber. S-FRP provides restoring force in 3 dimension. A prototype of S-FRP and its basic characteristics are shown. Moreover, a prototype of KEIROKA-assistive suit using S-FRP for supporting back bend mot...

Many assistive technologies to reduce work load have been proposed. However, the effects of these technologies are not sufficiently verified from a long-term standpoint. In this study, we tried to evaluate the influence of long-term farm work using a passive power assist suit on the physical function by daily measurement of physical fitness.

We developed real-time living activity measurement system that monitored heart beat information and the bodily movement from a photoplethysmography and a acceleration sensor. The outside optical noise reduction technique was performed by the pulse luminescence of LED and high-pass filter proccess. Discerning the basic motion running, walking, and w...

Bio-absorbable granules originated from animal bone were easily prepared by using high velocity rotation- crushing apparatuses. Frozen bovine bone, porcine bone and human femoral bone were crushed together with saline ice for 1 min under 12,000 rpm-rotation number of a stainless-blade in a stainless vessel or a ZrO2-blade in a ZrO2 vessel. The crus...

Our purpose in this study is to achieve an independent life and a social involvement for the elderly using KEIROKA (fatigue-reduction) Technology which makes it possible to improve the quality of chores and occupations by removing excessive strain and tiredness. Along the way, various assistant technologies for work and task supports have been sugg...

Snow shoveling is generally considered to be undesirable type of exercise from the reasons of requirement of higher cardiovascular function. The upper body takes the deep flexion posture by the snow-lifting work, and load concentrates on a spinal column and the back. To overcome the posture load, a modified handle was designed. This handle has S-sh...

Human hand achieves complex and various actions with cooperative activities of muscles in the forearm. Muscles' activity measurements are available to evaluate the work efficiency of human hands operations and quantify the degree of disease related in the hands. Surface electromyography (EMG) is a generally used method for the measurement using som...

A method for gait analysis using wearable acceleration sensors and gyro sensors is proposed in this work. The volunteers wore small sensor unit that included a tri-axial acceleration sensor and three mono-axis gyro sensors. The angular velocity data measured by gyro sensors were used to estimate the translational acceleration during gait. The trans...

Measurements by surface electromyography (sEMG) are noninvasive and simple to apply to obtain signals of muscle action potentials. However, the sEMG potentials of muscles near the electrode are superimposed. This paper develops a method measuring individual muscle activity and imaginary joint moment of forearm muscles using sEMG distribution and a...

Farmers and farm workers face some of the highest risks of work-related musculoskeletal injury caused by forward bending posture of the crop work or the heavy weight transportation. Therefore we performed biomechanical assessment for identifying risk factors involved in agricultural manual work. In this study, we developed the prototype personal we...

A method for gait analysis using wearable acceleration sensors and gyro sensors is proposed in this work. The volunteers wore sensor units that included a tri-axis acceleration sensor and three single axis gyro sensors. The angular velocity data measured by the gyro sensors were used to estimate the translational acceleration in the gait analysis....

Measurements by surface electromyography (sEMG) are noninvasive and simple to apply to obtain signals of muscle action potentials. However, the sEMG potentials of muscles near the electrode are superimposed, called "crosstalk". This paper develops a method measuring individual muscle activity of forearm muscles using sEMG distribution and a conduct...

Determining muscle forces of the finger during heavy work is important for an understanding and prevention of tenosynovitis. Electromyography is one index of muscle activity. Measurements by surface electromyography (sEMG) are noninvasive and simple to apply to obtain signals of muscle action potentials. The sEMG potentials of muscles near the elec...

A novel method for measuring human gait posture using wearable sensor units is proposed. The sensor units consist of a tri-axial acceleration sensor and three gyro sensors aligned on three axes. The acceleration and angular velocity during walking were measured with seven sensor units worn on the abdomen and the lower limb segments (both thighs, sh...

This work proposes a method for measuring human gait posture using wearable sensors. The sensor used consist of a tri-axial acceleration sensor and three gyro sensors aligned on three axes. These are worn on the abdomen and the lower limb segments (both thighs, both shanks and both feet) to measure acceleration and angular velocity during walking....

Surface electromyography (sEMG) is commonly used to measure muscle activity because of easy application. Advantages of sEMG measurements include noninvasiveness and no pain. However, there are also problems with the sEMG technique when the activities of individual muscles are measured. The measurement of activity of individual muscles in the forear...

Determining muscle forces of the finger during heavy work is important for an understanding and prevention of tenosynovitis. Electromyography is one index of muscle activity. Measurements by surface electromyography (sEMG) are noninvasive and simple to apply to obtain signals of muscle action potentials. The sEMG potentials of muscles near the elec...

This work proposes a method that can measure the three-dimensional positions of joint centers for hip, knee and ankle using wearable acceleration and gyro sensors. Healthy volunteers wore small sensor unit that included a tri-axis acceleration sensor and three single axis gyro sensors. Acceleration data from acceleration sensors and angular velocit...

For the process of product design and development, a technological tool, which quantitatively evaluates the usability of human for the product in advance, has been investigated and developed in the field of design engineering. The computer manikin is expected in order to design welfare products considering the physical performance of the human user...

It is difficult to drive a wheelchair through snow, because of swamping caster tire. In this study, we developed a prototype of a motorized crawler with a drive assist unit that can be installed in a standard manual wheelchair. The user can operate the crawler's steering and pitching with a handlebar, therefore the unit has a high performance on sn...

Low back pain is one of the most serious diseases in a work. It is important to prevent low back pain. In order to predict the muscle force in the lifting work, the musculoskeletal model was developed in this study. Twenty-four major muscles in a truncus and femurs were selected. Five lifting motions were measured by two video cameras. The successi...

This paper describes a method of numerical analysis of muscle force in a human upper limb during flexion of the forearm joint. Muscles were modeled by a straight line from the origin to the insertion. The optimization method of sequential quadratic programming was applied to this analysis. Restrictions in the object function of the optimization met...

Considering the human upper limb from the viewpoint of mechanics, every degree of freedom of motion is actuated and controlled by more than two muscles. In this paper we describe a method of numerical analysis of muscle force in a human upper limb during pronation-supination of the forearm joint. Because no muscle force can be calculated from only...

Observing the human upper limb from the point of view of mechanics, every degree of freedom of motion is actuated and controlled by more than two muscles. Many biomechanical researchers have investigated the principles of the complex workings of human muscles using a mechanomathematical model, to obtain more knowledge about the musculoskeletal syst...