著者

高松 潤二 阿江 通良 藤井 範久

出版者

社団法人日本体育学会

雑誌

体育學研究 (ISSN:04846710)

巻号頁・発行日

vol.42, no.1, pp.19-29, 1997-05-10

被引用文献数

5

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The purpose of this study was to develop a DLT procedure using pan and tilt cameras (henceforth, panning DLT) for the collection of three-dimensional coordinates data in large measurement volumes. Two stationary VTR cameras and two pan and tilt VTR cameras were used to obtain images of two control volumes. Two control volumes were used to compare the accuracy of coordinates data taken from stationary DLT with that of panning DLT technique: control volume A (CV-A) was 1.25×10×5m^3, and control volume B (CV-B) was 1.25×5×3m^3 in dimension. Control points and a ball thrown in each control volume were videotaped. DLT parameters for panning technique were calculated as follows: (1) Relative coordinates of control points to reference points were calculated from the digitizer coordinates of the reference points and control points. (2) Digitizer coordinates of the reference points and target objects were digitized. (3) Virtual control points were reconstructed from the relative coordinates of the control points in each frame. (4) Virtual control points appeared in the view of each camera were selected and used for the calculation of DLT parameters. Three-dimensional coordinates of control points were computed, and RMS errors were compared between stationary and panning DLT techniques. In CV-A of large volume, RMS errors of control points in stationary and panning DLT techniques were 14.0 and 7.5mm, respectively, while in CV-B of small volume, there was no significant difference in RMS errors, 8.3 and 5.8mm, respectively. Vertical accelerations of a thrown ball computed with two techniques were 9.74 and 9.71m.s^<-2> in CV-A. These results reveal that panning DLT technique developed in this study can be adapted for the collection of three-dimensional coordinates data in large measurement volumes.

著者

伊藤 信之 新井 健之 深代 千代 阿江 通良

出版者

社団法人日本体育学会

雑誌

日本体育学会大会号

巻号頁・発行日

no.43, 1992-10-31

著者

阿江 通良 岡田 英孝 尾崎 哲郎 藤井 範久

出版者

バイオメカニズム学会

雑誌

バイオメカニズム学会誌 (ISSN:02850885)

巻号頁・発行日

vol.23, no.2, pp.112-121, 1999

被引用文献数

6 4

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The purpose of this study was to investigate motion patterns for elderly people stepping over obstacles with a videography by comparing with those of the young. Crossing speed, step length, and step frequency of the elderly were significantly smaller than those of the young. With an increase in obstacle heights, crossing speed and step frequency decreased in the elderly, but there was no significant change in those of the young. With increased obstacle heights, the elevation of the lead leg increased in both groups, depending more on the elevation of the thigh and the flexion of the hip and ankle joints for the elderly, and the elevation of the shank and knee flexion for the young. In the elderly, the range of motion for the upper arm was significantly smaller than that of the young, and the forward lean of the trunk increased after landing of the lead leg at high obstacle. This may have made the clearance of the trail leg easier.

著者

加藤 謙一 山中 任広 宮丸 凱史 阿江 通良

出版者

社団法人日本体育学会

雑誌

体育學研究 (ISSN:04846710)

巻号頁・発行日

vol.37, no.3, pp.291-304, 1992-12-01

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The purpose of this study was to investigate cross-sectionally the development of running speed, step frequency, step length, running form, and maximal anaerobic power (MAnP) in high school boys. Subjects were 134 high school boys ranging from fifteen to seventeen years of age. They participated in power tests including the 50 m dash, maximal bicycle pedalling, vertical jump and long jump. They were videotaped during the 50 m dash to analyze their running form.Variables analyzed were: 1) 50 m running time, running speed, step frequency and step length, 2)step time, support time and non-support time, 3) path of the whole body center of gravity (CG),4)maximal anaerobic power, vertical jump, and long jump. The results were summarized as follows; 1. The running time for 50 m decreased from 7.44 s to 7;14 s with age. Running speed increased from 7.70 m/s to 8.00 m/s with age. Step frequency increased, while step length and step length/body height ratio showed no significant change. The increase in running speed resulted, therefore, from the increase in step frequency rather than the step length. 2. MAnP increased from 766.0 W to 823.6 W with age, but no noticeable change occurred in the MAnP/body weight. 3. At each age, significant correlations were found between step frequency, step length,and step length/body height except step length/body height of fifteen year old boys. Furthermore, running speed and variables for physical fitness such as MAnP showed significant correlations. Running speed and MAnP/body weight showed a significant correlation for each age group. 4. The relationship between running speed and the CG motion indicated that it was important to shorten support time, increase step frequency and reduce the bouncing motion of the CG in order to improve running speed. The relationship between running speed and the motion of the lower limbs suggested that motion of the toe relative to the hip during support phase, forward motion of the free leg and backward swing motion of the toe prior to foot contact at high speed help to improve running speed. 5. Based on the averages and the standard deviations of variables examined for each age group, running performance was classified into five categories. Averages of step frequency, step length, step length/body height, MAnP/body weight, vertical jump and long jump for the categories were listed in Table 6. This will be useful to evaluate the running performance of students and teach sprint running in physical education classes.

著者

阿江 通良 藤井 範久

出版者

筑波大学

雑誌

基盤研究(C)

巻号頁・発行日

2002

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本研究では,小学1年生から6年生までの児童284名(男子141名,女子143名)の歩行動作の計測を行い動作データを収集した.得られたデータをもとに小学生の歩行動作の標準的動作パターンを作成した.また青年および高齢者の歩行動作と比較することにより,小学生の歩行動作の特徴を明らかにした.1.小学生の歩行動作の特徴歩行速度,ステップ長,ステップ頻度に関しては,以下の特徴が見られた。(1)学年とともに歩行速度・ステップ長,歩行比が大きくなり,ステップ頻度は小さくなった.また男子の方が女子より歩行比が大きく,ステップ頻度が小さかった.(2)歩行パターンは,学年とともにステップ頻度依存からステップ長依存に変わり,小学生以降さらにステップ長に依存していくと考えられる.また男子の方が女子よりステップ長に依存していた.また、動作に関しては,以下のような特徴が見られた.(1)支持期の股関節は男子の方が女子より伸展しており,これは体幹が起きており,R-on時の大腿の後傾が小さく,L-on時の前傾が大きいためであった.(2)男子より女子の方が膝関節,下腿および足の動作範囲が大きかった.2.小学生の歩行動作に関するデータベースの構築ステップ長,ステップ頻度,歩行速度,歩行比(ステップ長/ステップ頻度),kinematics(身体重心の軌跡,関節および部分角度など),kinetics(回復脚の関節トルクおよび関節トルクパワー)などを算出し,学年,性別に着目してまとめた.そして,身体各部の2次元座標をもとに標準的動作を学年,性別ごとに作成し,stick picturesで表示できるようにした.