著者

木下 まどか 藤井 範久

出版者

バイオメカニズム学会

雑誌

バイオメカニズム (ISSN:13487116)

巻号頁・発行日

vol.22, pp.143-154, 2014 (Released:2017-02-15)

参考文献数

12

被引用文献数

1

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本研究の目的は, テコンドーの前回し蹴りを三次元動作分析することで, テコンドー特有の 「速い」 かつ 「早い」 蹴り動作について知見を得ることであった. そこで, 蹴り脚のキックスピードに対する下胴および蹴り脚各関節の運動におけるキネマティクス的貢献を算出した. その結果, インパクト時の膝関節伸展動作による貢献はキックスピードの約60%を占めていた. 上位群は下胴左回旋, 股関節屈曲角速度を適切なタイミングで大きくすることにより, 膝関節伸展に作用する膝関節力を生成していた. したがって, 膝関節伸展動作による貢献を増加させ, 「速い」 かつ 「早い」 蹴り動作を行うために, 下胴および股関節の動きが重要であると推察された.

著者

山崎 信寿

出版者

バイオメカニズム学会

雑誌

バイオメカニズム (ISSN:13487116)

巻号頁・発行日

vol.10, pp.85-95, 1990-09-10 (Released:2016-12-05)

被引用文献数

1

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Bipedal dinosaurs are huge and curious animals that have short forelimbs, powerful hindlimbs, and a long and heavy tail. The restoration of their posture and locomotion is difficult because of the lack of resemblant living animals. In this study, we paid attention to the harmony between animal motion and body shape, and conversely estimated the posture and locomotion of the bipedal dinosaurs from the characteristics of the body proportions using a computer simulation method. The mathematical model was constructed by the three-dimensional rigid link system with the following fourteen segments: head, neck, thorax, pelvis, upper arms, forearms, thighs, shanks, bottom tail, and top tail. An axis of the central body segments rotates about the vertical axis with a constant pitch angle defined by the initial posture. Each limb moves in the sagittal plane of the thorax or pelvis segment. Body weight is supported by the lumbar joint. Both torque spring and damper element are attached in each joint to prevent large relative rotation. Nonlinear elasticity is given in the knee and elbow joints to avoid hyper-extension of the joint. Using these assumptions, we can deduce seventeen simultaneous second-order differential equations. The numerical calculation of the oscillation mode was performed by using the fourth-order Runge-Kutta method. By means of this method, we analyzed Allosaurus, which was a typical bipedal dinosaur in the Jurassic period. The length of each segment was estimated from measured data of fossil skeletons. Other physical parameters, such as weight, moment of inertia and center of mass of each segment, were calculated geometrically from the restored shape. The torque spring and damper elements of each joint were referred from living animals. The numerical calculations were performed by assuming several body proportions and postures. The following results were obtained: Stability and walking speed with erect posture are inferior to the horizontal posture. The long and heavy tail is useful to obtain harmonic motion and greater speed. But the weight of the short forelimbs has almost no effects on the locomotion. The narrow distance between the hip joints increases the walking speed and decreases the swing of the body. The walking speed calculated by the stride of fossil pit and the oscillation frequency of the hindlimbs is 5.6km/h, which is within the speed range of mammals. Consequently, we can reconstruct the walking of Allosaurus, which held its trunk and tail horizontal and moved stably at almost mammalian speed.

著者

山崎 信寿

出版者

バイオメカニズム学会

雑誌

バイオメカニズム (ISSN:13487116)

巻号頁・発行日

vol.10, pp.85-95, 1990

被引用文献数

6 1

---

Bipedal dinosaurs are huge and curious animals that have short forelimbs, powerful hindlimbs, and a long and heavy tail. The restoration of their posture and locomotion is difficult because of the lack of resemblant living animals. In this study, we paid attention to the harmony between animal motion and body shape, and conversely estimated the posture and locomotion of the bipedal dinosaurs from the characteristics of the body proportions using a computer simulation method. The mathematical model was constructed by the three-dimensional rigid link system with the following fourteen segments: head, neck, thorax, pelvis, upper arms, forearms, thighs, shanks, bottom tail, and top tail. An axis of the central body segments rotates about the vertical axis with a constant pitch angle defined by the initial posture. Each limb moves in the sagittal plane of the thorax or pelvis segment. Body weight is supported by the lumbar joint. Both torque spring and damper element are attached in each joint to prevent large relative rotation. Nonlinear elasticity is given in the knee and elbow joints to avoid hyper-extension of the joint. Using these assumptions, we can deduce seventeen simultaneous second-order differential equations. The numerical calculation of the oscillation mode was performed by using the fourth-order Runge-Kutta method. By means of this method, we analyzed Allosaurus, which was a typical bipedal dinosaur in the Jurassic period. The length of each segment was estimated from measured data of fossil skeletons. Other physical parameters, such as weight, moment of inertia and center of mass of each segment, were calculated geometrically from the restored shape. The torque spring and damper elements of each joint were referred from living animals. The numerical calculations were performed by assuming several body proportions and postures. The following results were obtained: Stability and walking speed with erect posture are inferior to the horizontal posture. The long and heavy tail is useful to obtain harmonic motion and greater speed. But the weight of the short forelimbs has almost no effects on the locomotion. The narrow distance between the hip joints increases the walking speed and decreases the swing of the body. The walking speed calculated by the stride of fossil pit and the oscillation frequency of the hindlimbs is 5.6km/h, which is within the speed range of mammals. Consequently, we can reconstruct the walking of Allosaurus, which held its trunk and tail horizontal and moved stably at almost mammalian speed.

著者

田中 惣治 山本 澄子

出版者

バイオメカニズム学会

雑誌

バイオメカニズム (ISSN:13487116)

巻号頁・発行日

vol.23, pp.107-117, 2016 (Released:2017-08-01)

参考文献数

9

被引用文献数

9 2

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麻痺側立脚期の膝関節の動きにより片麻痺者の歩行パターンを分類し, 歩行パターンの違いにより歩行時の下肢筋活動と運動力学的特徴が異なるか, 三次元動作分析装置と表面筋電計を用いて分析した. 回復期片麻痺者35名を対象とし, 歩行時の膝関節と下腿傾斜角度から, 健常者の膝の動きと近い健常膝群 (15名), 荷重応答期と単脚支持期にそれぞれ膝関節が伸展する初期膝伸展群 (5名) と中期膝伸展群 (15名) に分類した. 結果, 健常膝群は荷重応答期で腓腹筋の筋活動を抑えながら前脛骨筋が働くため十分な背屈モーメントを発揮し, 踵ロッカーが機能した. 中期膝伸展群は荷重応答期で腓腹筋の筋活動が大きいため背屈モーメントが十分に発揮されず, 踵ロッカー機能が低下しており, 初期膝伸展群は荷重応答期で前脛骨筋の筋活動が小さく背屈モーメントが発揮されないことから, 踵ロッカーが機能しないことが明らかになった.

著者

高林 知也 江玉 睦明 横山 絵里花 徳永 由太 久保 雅義

出版者

バイオメカニズム学会

雑誌

バイオメカニズム (ISSN:13487116)

巻号頁・発行日

vol.23, pp.67-73, 2016 (Released:2017-08-01)

参考文献数

32

被引用文献数

1

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ウィンドラス機構 (WM) とは歩行時の蹴り出し時の推進力を生み出す足部機能のひとつであり, 効率的な歩行を実現するために重要な役割を担っている. しかし, 走行におけるWMはいまだ明らかとなっていない. 本研究は, 走行と歩行の動作様式の違いがWMにおよぼす影響を検証した. 対象は健常成人男性9名とし, 課題動作はトレッドミル上での走行と歩行とした. 解析項目として, WMの指標である内側縦アーチ角度と母趾背屈角度を立脚期で算出した. 走行と歩行で内側縦アーチ角度最小値は変化がみられなかったが (157.4±6.0°, 156.9±4.9°), 走行は歩行と比較して母趾背屈角度ピーク値が有意に低値を示した (32.9±7.3°, 39.9±9.0°; p<0.05). 本研究結果より, 走行時のWMの役割は限局的である可能性が示唆された.

著者

高橋 良輔 金子 文成 柴田 恵理子 松田 直樹

出版者

バイオメカニズム学会

雑誌

バイオメカニズム (ISSN:13487116)

巻号頁・発行日

vol.24, pp.59-67, 2018 (Released:2019-09-01)

参考文献数

28

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本研究の目的は, 肩関節外旋運動反復トレーニングが肩関節外転運動中の棘下筋を支配する皮質脊髄路興奮性を増大させるのか明らかにすることである. 外旋反復運動をトレーニング課題として, その前後に外転運動中の皮質脊髄路興奮性を経頭蓋磁気刺激による運動誘発電位で評価した. 外旋反復運動は15分毎に100回を3セット実施した. 運動誘発電位は外旋運動反復トレーニング前に2回, 各トレーニング直後, そして3回目のトレーニング直後から30分後と60分後に測定した. 棘下筋の運動誘発電位振幅は3回目のトレーニング直後から60分後まで有意に増大した. 本研究結果から, 肩関節外旋運動反復トレーニングによって, トレーニングと異なる運動である肩関節外転運動中に棘下筋を支配する皮質脊髄路興奮性が持続的に増大することが示された.

著者

板谷 厚 小野 誠司 木塚 朝博

出版者

バイオメカニズム学会

雑誌

バイオメカニズム (ISSN:13487116)

巻号頁・発行日

vol.25, pp.33-44, 2020 (Released:2021-07-16)

参考文献数

27

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本研究は, 男子大学野球部員20名を対象者とし, 盗塁をモデル化したスプリント走 (投手の投球動画を見て打者方向への投球だと判断した時点でスタートし10 mを全力疾走する) 24試技を実施した. スプリント走タイムとスタート時の投球方向予測の確信度をvisual analog scaleにて測定した. 各対象者のタイムと確信度は総じて負の相関関係にあり, 確信度が高いほどタイムは短縮する傾向にあった. したがって, 盗塁のような予測をともなうプレーは予測が外れ失敗するリスクはつきものだが, 判断に確信をもつことでパフォーマンスは向上し, 成功の可能性を高めることが示唆された.

著者

金原 秀行 岩本 正実

出版者

バイオメカニズム学会

雑誌

バイオメカニズム (ISSN:13487116)

巻号頁・発行日

vol.22, pp.189-199, 2014 (Released:2017-02-15)

参考文献数

24

被引用文献数

1 2

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アメフトは, 軽度の外傷性脳損傷 (MTBI) が最も多く発生する競技といわれている. 我々は頭部の角加速度の大きさとその持続時間に基づいた脳傷害評価指標RIC36とPRHIC36を提案している. 本研究ではアメフト衝撃時の頭部の加速度データを取得し, スポーツにおけるMTBIを対象とした脳傷害評価指標の妥当性と有用性について示す. 頭部の衝撃挙動についてよく検証された人体有限要素 (FE) モデルを用いて, アメフト衝撃時の頭部挙動を再現し, 頭蓋内の脳ひずみを予測した. 頭部挙動と脳ひずみの関係を調査した結果, RIC36とPRHIC36は脳ひずみから推定される脳損傷率と強い相関を示した.

著者

竹田 仰

出版者

バイオメカニズム学会

雑誌

バイオメカニズム (ISSN:13487116)

巻号頁・発行日

vol.12, pp.265-279, 1994-08-10 (Released:2016-12-05)

参考文献数

28

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This paper reports on a virtual training environment developed using virtual reality technology with force and visual image feedback capability. In our system: (1) A light and safe force-display implemented using a pneumatic rubber actuator is available. It has a wide range of motion and large driving force comparable to those of human joints and muscle. (2) The trainee's muscle characteristics can be measured. (3) The parameters of the training environment (e. g. spring constant, weight of dumbbell) can be changed easily so as to obtain an environment best fitting the characteristics of human muscle. In order to accomplish the above purposes, a system must be capable of freely generating and controlling the physical and psychological elements of a training environment. For the first step, applying virtual reality techniques, we are developing a computer controlled training system which can generate and control various audio/visual images and forces to be applied to the trainee. Currently, however, we have decided to limit the scope of implementation to the upper extremity as the training target, and to visual images for the environmental information. The trainee using this system wears a force-display which can apply force to his/her upper extremity and a head mount display through which he/she can see the virtual world, a room with wall, windows, etc., in which a spring and a dumbbell are placed in the room. The trainee can "use" these sporting goods and can feel forces on his/her upper extremity as if he/she were actually exercising using them. By measuring the trainee's muscle characteristics and setting them in the system's computer before starting a training session, an improved training environment results. In addition, in the case of rehabilitation, the system can provide information such as video images of rehabilitation history data, which can help increase the trainee's motivation for attending the exercise. In our system, an important role is played by the actuators which are attached to the force-display to generate various reaction forces. An actuator serving those purposes should be safe, small, light, and capable of high force output. As human muscle of the upper extremity is much stronger than the muscle of the fingers, an actuator with high output is very desirable. It is also important that the apparatus not feel unpleasant to the trainee when he/she wears the force-display. For these reasons, we have chosen a pneumatically controlled rubber actuator.

著者

平野 剛 那須 大毅 小幡 哲史 木下 博

出版者

バイオメカニズム学会

雑誌

バイオメカニズム (ISSN:13487116)

巻号頁・発行日

vol.22, pp.27-36, 2014 (Released:2017-02-15)

参考文献数

13

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ホルン演奏時の表情筋の制御様式と熟達度によるその違いを調べるために2つの実験を行った. 第1実験では熟達奏者にさまざまな音を演奏させ, 音が鳴る直前と音が鳴っているときの表情筋の活動と唇周りの皮膚表面の動きを計測した. その結果, 音が鳴る直前の活動強度と音が鳴っているときの活動強度の間に差はみられなかった. また計測されたほとんどの筋で演奏する音量が大きいほど, また演奏する音の高さが高いほど筋活動量は高くなった. 一方で口唇周りの皮膚表面の動きは, 演奏する音量, 音の高さにかかわらず一定だった. この結果から, 熟達ホルン奏者は意図した音に応じて, 音が鳴る直前から広範囲の表情筋の活動を共同的に制御し, 振動する唇の張力や質量を変化させていることが示唆された. 第2実験では熟達奏者と未熟達奏者の2群に分けて, 表情筋の活動の違いを検討した. その結果, 連続しない1つの音を演奏する課題では活動量に違いはみられないが, 異なる音の高さを連続して演奏する課題では, 上唇に付着する筋に活動量の違いが見られた. 上唇に付着する筋の活動は, 複雑な演奏を行うときに重要な役割を果たし, その制御には長期的な訓練を要することが示唆された.

著者

広瀬 茂男 梅谷 陽二

出版者

バイオメカニズム学会

雑誌

バイオメカニズム (ISSN:13487116)

巻号頁・発行日

vol.5, pp.242-250, 1980-05-25 (Released:2016-12-05)

被引用文献数

3 7

著者

眞鍋 芳明 桜井 健一 岩壁 達男 尾縣 貢

出版者

バイオメカニズム学会

雑誌

バイオメカニズム

巻号頁・発行日

vol.19, pp.69-80, 2008

被引用文献数

1

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<p>本研究の目的は, スクワットトレーニングにおける運動速度を含むトレーニングプロトコルの違いが筋断面積, 筋力および運動パフォーマンスに与える影響を検証することである. 被検者を高重量・低回数負荷で行うStrength群, 5秒間かけて下降および挙上を行うSlow群, そして軽重量を用いて全運動範囲において最大速度で行うSpeed群の3群に分け, 6~8週間のトレーニング前後に身体組成, 筋力および運動パフォーマンステストを実施した. その結果, Slow群においては筋肥大が確認されたものの, 運動パフォーマンスは向上せず, Strength群およびSpeed群においては, 身体組成においては変化が認められなかったが, 跳躍および30m疾走パフォーマンスの向上が認められた.</p>

著者

増田 正 遠藤 博史 武田 常広

出版者

バイオメカニズム学会

雑誌

バイオメカニズム (ISSN:13487116)

巻号頁・発行日

vol.15, pp.63-73, 2000-06-15 (Released:2016-12-05)

参考文献数

17

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In recent years SQUID (Superconducting Quantum Interference Device) technology has developed rapidly in both sensitivity and number of recording channels. Biomagnetic measurements based on SQUID technology are considered to have great potential in the analysis of brain and heart functions. They are also applicable to skeletal muscles and may provide a new method for diagnosing neuromuscular functions. To clarify the capability for biomagnetic measurements, the magnetic recording technique was applied to the vastus lateralis and the vastus medialis of three healthy male adults. Magnetic fields were measured with a 64-channel SQUID system. Discharges of single motor units were simultaneously detected by surface electromyography under a weak voluntary contraction. The magnetic signals were averaged for 64 to 158 times at the zero-crossings in the surface electromyogram. Six motor units were detected in the three subjects. The isofield maps of magnetic fields showed current sources arising from the motor endplate regions and spreading in opposite directions to the tendons. A current octupole moving along muscle fibers explains these magnetic fields. Because the magnitude of the magnetic fields is directly proportional to the intensity of the currents in the muscle fibers and is independent of the conductivity of the surrounding medium under certain conditions, it is possible to calculate the intensity of the currents in the muscle fibers. To improve the accuracy of such calculations, a model of the muscle fiber action currents was developed, taking into consideration the intensity and duration of the current source. A magnetic field was calculated from an octupole current model. The measured magnetomyographic signal waveform was deconvoluted with the calculated magnetic field signal produced by a single muscle fiber. The area of the deconvoluted waveform represents the number of active muscle fibers, which was estimated at 708 to 1,791 (average 1,088±480) for the six motor units detected. These numbers were 6.5 times larger than those estimated from the intensity of the current source alone without considering its duration, and were close to the invasively obtained values. The number of muscle fibers contained in a muscle or a motor unit has until now been estimated only by an anatomical method. Noninvasive magnetic measurement should therefore contribute to the diagnosis of neuromuscular diseases that cause the decrement or shrinkage of muscle fibers.

著者

山崎 信寿 高橋 直己

出版者

バイオメカニズム学会

雑誌

バイオメカニズム

巻号頁・発行日

no.17, pp.235-244, 2004-08-25

被引用文献数

5

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Body care motions apply a large amount of stress on caregivers' muscles and spines, so most of them suffer from low back pain. One of the major factors of low back pain is the low back muscular load to keep the deep flexion posture. This study concerned development of a suit-type back muscle supporter named "the care suit," which reduces low back load. Elastic fiber belts (support lines) are arranged on the back and leg parts of the suit. The support lines are relaxed so as not to interfere with daily trunk motion, arm motion, walking, and sitting motion, but to exert tensile force and extension moment in the deep flexion posture. The care suit is a two-piece design to improve comfort and convenience. To optimize the layout of the support lines we developed a small reel-type device to measure body surface deformation. As the result of measurement by this device and a system for posture measurement during several motions, the back support lines are arranged in an x-shape from the side neck point to the point internally dividing the Jacoby-line at a ratio of 1 to 2. The leg support lines branch at the rear face of the thigh and are attached to the apex of the patella. The maximum tension of support lines is limited by the user's shoulder pain to 140 N for males and 85 N for females. The effect of the care suit was evaluated by electromyograms of back muscles. The action potential in the deep flexion posture was 25% decreased. In comparison with the conventional corset, the effect of the care suit for back muscle was equal, but the care suit is superior in that it does not interfere with flexion motion. The lumbar joint muscular moment during a diaper change operation was calculated from body posture through a rigid body link model. The results of this calculation showed that the stored load during the operation was decreased by 30% by the care suit. Furthermore the summation of intervertebral disk compressive force was reduced by 15% during the operation. Therefore the care suit is effective for reduction of not only continuous muscular load but also spinal load. Practical use by caregivers also resulted in good evaluations as it reduced continuous muscle load for a diaper change operation, bed making operation, etc. Conclusively, the low back load during body care motions can be reduced by the care suit developed in this research. This care suit is under patent application.

著者

高西 淳夫 谷 知之 田名瀬 崇 加藤 一郎

出版者

バイオメカニズム学会

雑誌

バイオメカニズム

巻号頁・発行日

vol.10, pp.71-81, 1990

被引用文献数

5 1

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Numerous studies on the neurophysiology and anatomy of the control system of mastication have been done, but most of them are only qualitative, not quantitative and dynamic. The authors believe that the mechanism of mastication can be analyzed quantitatively using a mathematical model and that an artificial mastication system can be developed on the basis of the results. The purpose of this study was to develop a 3 DOF (degrees of freedom) artificial mandible model WJ (Waseda Jaw)-2 and to simulate mandible motion in mastication. We hypothesized that a mandible modeled as a rigid body has 4DOF because the left and right condylar paths are constrained by the kinematic axis. The WJ-2 has 3DOF since the thrust movement along the kinematic axis is so small that it can be negligible. Artificial muscle actuators (AMAs) using DC servo motors drive the WJ-2. The WJ-2 has four kinds of AMAs: the m-colliant. (to open), the m-masseter (to close), the m-pterygoideus lateralis (to move forward), and the m-temporalis post. (to move backward). They are assigned around the jaw with reference to the anatomic data and the authors' computer simulation. We decided that the incisal point tracing shown by Gysi is the target motion of the WJ-2. It consists of 4-phases. Phase 1 is the opening phase, 2 is the turning phase (opening to closing), 3 is the closing phase, and 4 is the occlusal phase. The authors considered that the incisal point tracing can be drawn by fixing the working side condyle, moving the balancing side condyle, and rotating the jaw around the kinematic axis. The authors have determined that there are 2 levels of control systems in mastication. One is the muscle control system of each masseter muscle, which is the lower-level system. The other is the mastication control system, the upper-level system, which supervises and controls the muscle control systems. The muscle control system controls the muscle by position and velocity feedback of the muscle spindle. Feedback gain is variable. The mastication control system creates movement patterns of the mandible, sends it to the muscle control system, and supervises jaw reflexes. The control sequence of the WJ-2 is also divided into 4 phases according to Gysi's theory. The change from the occlusal to the opening is under the control of a normal position pattern. The jaw opening reflex and unloading reflex are used when accidents occur in mastication. And the WJ-2 has the function that the maximum mandible opening position changes adaptively as food is deformed. The authors conducted a mastication experiment with food. As a result, the WJ-2 realized mandible movement that suits Gysi's 4-phase theory and realized mastication movement that matches deformation of food.

著者

藤本 浩志 滝田 久芳 有田 道生 小金沢 鋼一 加藤 一郎

出版者

バイオメカニズム学会

雑誌

バイオメカニズム

巻号頁・発行日

vol.9, pp.241-251, 1988

被引用文献数

4 3

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Conventional A/K prostheses have been designed only for level walking, so A/K amputees have been compelled to walk on stairs with unnatural posture. To expand A/K amputees' daily mobility, the goal of this study is to develop an A/K prosthesis which allows amputees to ascend/descend stairs as well as to walk on a flat surface. The WLP-8 R developed in our study featured a mechanism that can generate a powerful moment at the joints large enough to ascend the stairs. First, this paper presents the Hydraulic/Electric Hybrid Actuator composed of a hydraulic power assembly and an electric power assembly to realize level and stairs walking. In level and downstairs walking, the amputee can walk only with the hydraulic power assembly that generates the extension moment of knee joint during a swing phase using the hydraulic power which has been previously accumulated by the passive rotation of the two joints (knee and ankle) during the last stance phase. So no additional power system is necessary as to realize level and downstairs walking. In upstairs walking, the amputee can walk using the Hydraulic/Electric Hybrid Actuator. The electric power is transmitted through the ball-screw driven by the DC motor to the piston-rod of the knee joint, which has also been pushed up by the hydraulic power as well as level walking so that the knee joint is extended by the combined powerful force of hydraulic and electric power. Second, the Automatic Dorsal-Flexion Mechanism that improves the posture during level walking is described. Third, the construction of the WLP-8 R system is described. Performance of amputees wearing the WLP-8 R and walking is described and discussed. Two A/K amputees could walk on a flat surface and stairs like normal subjects. These walking experiments confirmed the applicability of this system.

著者

阿江 通良 宮下 憲 飯干 明

出版者

バイオメカニズム学会

雑誌

バイオメカニズム

巻号頁・発行日

vol.9, pp.105-113, 1988

被引用文献数

3 2

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The purposes of this study were to analyze energy flows between lower limb segments during a cycle of sprinting and to clarify the characteristics of two different running motions, starting dash and sprinting at a constant speed, by comparing their energy flows. Three male sprinters dashed 20m and ran 100m giving their full effort. They were filmed at the 1-step and 5-step points after the start and at the 80m mark of the 100m sprint with a motion-picture camera. Ground reaction force data were simultaneously sampled at 500Hz. Digitized x and y coordinates of the body marks were smoothed by a digital filter cutting off at 8Hz for the start dash and 10Hz for sprinting. A 14-segment link modelling was used to compute linear and angular kinematics, joint forces, and net muscle moments. Joint force and muscle moment powers (abbreviated JP and MP) were computed as defined by Robertson and Winter (1980). Analysis and comparison of energy flow in a starting dash and sprinting at a constant speed revealed that: 1) Magnitude of energy flow by JP was much greater than that of MP in sprinting, while the difference in power level of JP and MP was less 1 step after the start. 2) In the early recovery period of sprinting, energy in the lower limb flowed from the trunk toward the foot, and it flowed in the reverse direction in the late recovery period. In the support period, the muscles at the ankle and knee joints absorbed most of the energy. Energy flowed from the trunk and thigh to the shank in the first half of the support period, and from the foot to the shank and from the trunk to the shank through the thigh in the second half. 3) In the recovery period of the starting dash energy flowed in the same manner as in sprinting. However, in the support period, the energy flowed from the foot to the thigh and the trunk. Notable was energy flow from the opposite thigh (i.e., the recovery thigh) to the trunk. From the viewpoint of energy flow patterns in the lower limb, a starting dash may be characterized as the running motion that accumulates as much mechanical energy in the trunk as possible through the generation of energy by the knee joint muscles and the transfer of energy to the trunk from the leg, especially the opposite leg at the support stage. Sprinting at constant speed may be characterized as the running motion to redistribute the energy between the body segments and the trunk with the minimum loss of energy.

著者

荻原 直道 工内 毅郎 中務 真人

出版者

バイオメカニズム学会

雑誌

バイオメカニズム

巻号頁・発行日

no.18, pp.35-44, 2006-09-15

被引用文献数

1

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ヒトの精密把握能力の形態的基盤の進化を明らかにするためには,ヒトと最も近縁なチンパンジー手部構造の形態と機能の関係を理解することが不可欠である.このためCTおよび屍体解剖により取得した形態学的情報を元に,チンパンジーの手部筋骨格系の数理モデルを構築した.本モデルを用いてチンパンジーの形態に規定される精密把握能力を生体力学的に推定し,ヒトの手と比較した結果,特に第1背側骨間筋の付着位置の違いが,ヒトに特徴的な優れた把握能力に大きく寄与していることが示唆された.

著者

広川 俊二 松村 公志

出版者

バイオメカニズム学会

雑誌

バイオメカニズム

巻号頁・発行日

vol.11, pp.153-165, 1992

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The anterior-posterior displacement of the tibia elicited by the loading of the quadriceps and hamstring muscles was determined as a function of joint angle and muscle load using the data collected from five fresh cadaver knees with a highly accurate computerized radio-graphic technique. A two-dimensional mathematical model, taking into account movements and forces of the patellofemoral and tibiofemoral joints in the sagittal plane, was described and a computer simulation was performed to verify the experimental results. The simulated and experimental results closely coincided. Both the results demonstrated that quadriceps contraction can result in an anterior displacement of the tibia in the range of 0°to 40°of flexion, and in a posterior displacement in the range of 80°to 120°of flexion. However, hamstrings contraction always causes a posterior displacement of the tibia, irrespective of knee flexion angle. Thus it was concluded that quadriceps contraction has a direct impact on ACL stress, as hamstring contraction does on PCL stress. It was further concluded, however, that the absolute magnitudes of both the cruciate ligaments were not so much influenced by the thigh muscles' contraction as they were influenced by knee flexion angle, a conclusion that throws into question the assessment of cruciate ligament stresses by anterior-posterior displacement of the tibia. Some useful parameters that serve as a function of knee flexion angle were also introduced through the simulation: contact force and slipping ratio of the patellofemoral and tibiofemoral joints, variation of the patellar ligament force, and thigh muscle length. There is a linear relationship between quadriceps muscle force and patellofemoral contact force, whereas there is little relationship between quadriceps muscle force and tibiofemoral contact force. A semilinear relationship is observed between knee flexion angle and patello-femoral contact force. The tibiofemoral contact force shows a bell-shaped pattern against knee flexion angle. Variation of the patellofemoral slipping ratio shows a complex form in which the glide and roll of the patella on the femur take place in the opposite direction for 0°to 95°of knee flexion while glide and roll take place in the same direction for more than 95°of flexion. Variation of tibiofemoral slipping ratio shows that the femur mainly glides on the same position of the tibia between 30°and 90°of knee flexion. Linear relationships do exist between knee flexion angle and, respectively, quadriceps length and hamstrings length. Patellar ligament force varies from a similar value to about 60% of the quadriceps force as the knee flexes.

著者

長谷 和徳 西口 純也 山崎 信寿

出版者

バイオメカニズム学会

雑誌

バイオメカニズム

巻号頁・発行日

vol.15, pp.187-198, 2000

被引用文献数

20 6

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Many computer simulation studies of human bipedal walking have been conducted in the field of biomechanics. The musculo-skeletal systems in previous models, however, have been simplified two-dimensionally, and theoretical methods in robotics have been applied for the motor control mechanisms. The purpose of this study was to develop a more precise simulation model of human walking in order to improve the practicability of the simulation method. As a result, a model was created in which the musculo-skeletal system of the entire body is modeled three-dimensionally, and a mechanism for motor control was constructed by a neuronal system model having a hierarchical structure. The inertial properties of the entire human body were represented by a three-dimensional , 14-rigid-link system. These links include the feet, calves, thighs, pelvis, lower lumbar region, upper lumbar region, thorax, upper arms, and forearms. The body's dynamic model is driven by 42 muscles for the entire body. The arrangement of each muscle was represented as a series of line segments, the direction of which changes according to joint angle. Energy consumption, including heat production, in the muscle was calculated from the generating tension. The hierarchical neuronal system includes three levels. First, at the highest level, there is a neuronal system corresponding to the higher center level. The function of adjusting changes in walking pattern is assumed to exist at this system level. The model was expressed by a computational multi-layered neural network. Second, at the middle level , there is a neuronal system corresponding to the spinal cord level. This neuronal system, representing a rhythm-generation mechanism, was modeled as a network system consisting of neural oscillators. They generate the neuronal stimulus combined for each degree of freedom by receiving nonspecific stimulus from the higher center and feedback signals from the somatic senses. Each neural oscillator is mathematically expressed by two differential equations. Third, at the lowest level, there is a neuronal system corresponding to the peripheral level. The neuronal system divides the combined neuronal stimulus from the neural oscillator into the neuronal stimulus to each muscle. The model is mathematically represented as an optimization problem. The simulated walking pattern was continuous and stable. The walking pattern closely agrees with actual human walking in terms not only of joint movement but also of muscle activities and energy consumption. In order to investigate the effects of higher center system functioning in adjusting walking patterns, we compared a walking pattern generated by a model incorporating a higher center system with the patterns obtained from a model without the higher center system, in terms of robustness of mechanical perturbation. Although the model without the higher center system could not stabilize its walking pattern and finally fell down, the model with the higher center system could perform continuous walking without falling down.