• 한국운동역학회지
• /
• 제24권4호
• /
• pp.317-327
• /
• 2014

As a single subject study, it was purposed to investigate kinematic differences between Yang Hak Seon vault (i.e., handspring forward and salto forward straight with triple twist, Yang-1 vault hereafter) and Tsukahara $1260^{\circ}$ twist with salto forward straight (Yang-2 vault hereafter) in gymnastics. Yang Hak-Seon (23 years, 160 cm, and 52 kg) voluntarily participated in this study. Motion capture system, consisting of fourteen cameras, were used to measure Yang-2 vault with the sampling rate of 200 Hz. Twenty six reflective markers were placed on major anatomical points of 15 body segments. Successful two trials of Yang-2 vault were collected and analyzed for the comparison. Compared Yang-1 results were based on the previous study of Park and Song (2012). Results indicated superior linear kinematics of Yang-1 vault to those of Yang-2 vault before the touchdown of vault table. However, Yang-2 vault revealed superior angular kinematics to Yang 1 vault showing more trunk twist angle (a triple and a half twist) and its faster angular velocity during the airborne. The Yang 2 vault could has advantage of increasing angular motion than Yang 1 vault as a result of a half turn off the springboard onto the vault table and a sequential touchdown of the hands.

• 한국운동역학회지
• /
• 제28권2호
• /
• pp.69-78
• /
• 2018

Objective: The purpose of this study was to investigate the feasibility of a new vault technique through a kinematic comparison of the YANG Hak Seon and Yeo 2 vaults. Method: The photographic images of the YANG Hak Seon and Yeo 2 vaults were collected using a high-speed camera, and their kinematic characteristics were analyzed using three-dimensional image analysis. Results: During the post-flight phase of the Yeo 2 and YANG Hak Seon vaults, the time of flight, height of flight, and flight distance were similar. At the peak of the post-flight phase, the trunk rotation angle of the YANG Hak Seon vault rotated $457^{\circ}$ more than did the Yeo 2 vault. During the post-flight descending period, the twist velocity of the trunk was much faster with the YANG Hak Seon vault ($1,278^{\circ}/s$) than with the Yeo 2 vault ($1,016^{\circ}/s$). Conclusion: To succeed in the new technique, the average twist velocity during post-flight must be maintained at $1,058^{\circ}/s$ and the twist velocity must be increased from the ascending phase.

• 한국운동역학회지
• /
• 제26권3호
• /
• pp.243-248
• /
• 2016

Objective: The aim of this study was to determine the kinematical characteristics of somersault with twist in the Lou Yun and Akopian motions and to provide useful information to gymnastic athletes in men's vault. Method: The study subjects were 12 male adult top athletes. After 12 trials (7 Lou Yun and 5 Akopian trials) filmed by using two digital high-speed camcorders set at 90 frames/sec, kinematical data were collected through the direct linear transformation (DLT) method. The mean differences in biomechanical variables were compared during the second flight upward phase. The kinematic characteristics of somersault with twist in the Lou Yun and Akopian motions were identified. Results: In Lou Yun motion, the vertical release velocity through horse breaking was not difficult to obtain, so the athletes had enough time to prepare for the twist. Therefore, the Lou Yun motion has an advantage to make a cat twist in the pike posture. In the Akopian motion, obtaining the horizontal velocity through horse pushing was so easy that the Akopian athletes attained a large angular impulse and angular momentum. Therefore, the Akopian motion has an advantage to making a tilt twist in the body tilting posture. Conclusion: This study suggests that gymnastic athletes should control their body segment movements in order to increase the twisting angular velocity of the whole body, which requires regulation of the longitudinal moment of inertia of the body. Moreover, athletes should prepare for the shoulder and hip twists early in order to make the landing position in advance.

• 한국운동역학회지
• /
• 제15권4호
• /
• pp.143-151
• /
• 2005

This study was conducted to investigate the technical factors of Cuervo forward straight vaults with single twist, single and half twists, and double twists actually performed by three execellent male gymnasts participated in artistic gymnastics competition of 2003 summer Universiade in Daegu and the 85th National Sports Festival in Cheongju. To accomplish the research goals the Cuervo vaults of three gymnasts were filmed by using three digital camcorders set by 60 Hz, and data were collected through the DLT method of three dimensional cinematography. The kinematic and kinetic variables as each phasic time, CM displacement velocity, release angle inclination angle hip joint angle landing angle, average horse reaction force average moment arm average torque, whoe body's total remote local angular momentum were analyzed, so the following conclusions were reached. Generally to perform the better Cuervo vault, a gymnast should touch down on the board with the great horizontal velocity of the whole body through the fast run-up, and touch down on the horse by decreasing the horizontal displacement of the whole body during the preflight, so raise CM height gradually within a short horse contact time. He should increase the horse reaction force through checking the horizontal velocity of the whole body effectively and the inclination angular displacement of the handstand, if so he can have the large vertical velocity of the whole body. By using the acquired the velocity and the angular momentum of the whole body, he can vault himself higher and twist sufficiently, then he can get better if the body could be tilted by swinging both arms and perform the cat twist with a little flexions at hip joints. According to the above outcomes we can judge that the best athletes is LuBin, the better is YTY, and the next is JSM.

• 한국운동역학회지
• /
• 제16권4호
• /
• pp.165-173
• /
• 2006

The purpose of this study was to analyze Yurchenko's 900 degree twist technique between the highly scored and the lowly scored subjects during the 2003 TaeGu Universiad Championship. The following results was obtained by analyzing horizontal, vertical and resultant velocities on 1st, 2nd, 3rd and 4th phases. The highly scored subject took longer total performance time but shorter time in 2nd and 300 phases. The highly scored subject also took longer performance time in 4th phase. In the board contact phase the highly scored subject had bigger elbow joint angle and shoulder joint angle. The highly scored subject had longer flying time and had more higher vertical height but lower horizontal and resultant velocities on 4th phase.

• 한국운동역학회지
• /
• 제13권3호
• /
• pp.81-98
• /
• 2003

The purpose of this study is to closely examine kinematic characteristics by jump phase of Li Xiaopeng motion in horse vaulting and provide the training data. In doing so, as a result of analyzing kinematic variables through 3-dimensional cinematographic using the high-speed video camera to Li Xiaopeng motion first performed at the men's vault competition at the 14th Busan Asian Games, the following conclusion was obtained. 1. It was indicated that at the post-flight, the increase of flight time and height and twisting rotational velocity has a decisive effect on the increase of twist displacement. And Li Xiaopeng motion showed longer flight time and higher flight height than Ropez motion with the same twist displacement of entire movement. Also the rotational displacement of the trunk at peak of COG was much short of $360^{\circ}$(one rotation) but twist displacement showed $606^{\circ}$. Likewise, Li Xiaopeng motion was indicated to concentrate on twist movement in the early flight. 2. It was indicated that at the landing, Li Xiaopeng motion gets the hip to move back, the trunk to stand up and the horizontal velocity of COG to slow down. This is thought to be the performance of sufficient landing, resulting from large security of rotational displacement of airborne and twist displacement. 3. It was indicated that at the board contact, Li Xiaopeng motion made a rapid rotation uprighting the trunk to recover slowing velocity caused by jumping with the horse in the back, and has already twisted the trunk nearly close to $40^{\circ}$ at board contact. Under the premise that elasticity is generated without the change of the feet contacting the board, it will give an aid to the rotation and twist of pre-flight. Thus, in the round-oH phase, the tap of waist according to the fraction and extension of hip joint and arm push is thought to be very important. 4. It was indicated that at the pre-flight, Li Xiaopeng motion showed bigger movement than the techniques of precedented studies rushing to the horse, and overcomes the concern of relatively low power of jump through the rapid rotation of the trunk. Li Xiaopeng motion secured much twist distance, increased rotational distance with the trunk bent forward, resulting in the effect of rushing to the horse. 5. At horse contact, Li Xiaopeng motion makes a short-time contact, and maintains horse take-off angle close to vertical, contributing to the increase of post-flight time and height. This is thought to be resulted from rapid move toward movement direction along with the rotational velocity of trunk rapidly earned prior to horse contact, and little shave of rotation axis according to twist motion because of effective twist in the same direction.

• 한국산학기술학회논문지
• /
• 제21권2호
• /
• pp.167-174
• /
• 2020

본 연구는 세계적인 선수를 대상으로 남자 기계체조 도마 종목에서 로페즈 기술을 수행했을 때 성공 동작과 실패 동작에 따라 운동학적 차이를 비교 분석하였다. 연구대상은 올림픽 금메달리스트 YHS 선수(나이: 27세, 신장: 160cm, 체중: 53kg중)이였고, 14대의 적외선 고속카메라를 이용하여 도마 동작을 촬영하였다. 원하는 동작 자료획득과 분석을 위해 19mm 반사 마커 26개를 해부학적 주요지점에 부착시켰고, 15개 분절 신체모델을 사용하여 운동학적 변인 계산을 실시하였다. 분석 결과 첫째, 구름판 접촉구간에서 성공 동작의 소요시간이 실패 동작보다 길었으며, 성공 동작은 슬관절의 가동범위를 실패 동작보다 크게 하였다. 둘째, 제1비약에서 성공 동작과 실패 동작의 소요시간은 동일하였다. 성공 동작은 실패 동작보다 짧은 수평이동을 했으며, 높은 수직위치와 도마 착지각을 보였다. 셋째, 도마 접촉구간에서 성공 동작의 소요시간이 실패 동작보다 짧았다. 성공 동작은 도마접촉 순간에 실패 동작보다 좌측 견관절각을 크게 하였다. 넷째, 제2비약에서는 성공 동작의 소요시간이 실패 동작보다 길었으며, 긴 수평이동을 나타냈다. 성공 동작은 도마이륙 순간 우측 견관절각을 크게 하였고, 비틀기 각속도는 빨랐다. 종합하면 YHS 선수가 안정적인 로페즈 기술을 구사하기 위해서는 도마접촉 순간에 높은 자세로 진입하여 도마이륙 순간에서는 우측 견관절각을 크게하여 빠른 비틀기 각속도를 만들어야 한다. 최대높이와 착지 순간에서는 좌·우견관절각을 작게하여 관성모멘트를 줄이고 신체중심을 낮춰야 할 필요가 있다.