• 한국콘텐츠학회논문지
• /
• 제9권12호
• /
• pp.364-375
• /
• 2009

본 연구는 하지 저항운동 시 고령자 보행의 하지분절과 관절의 운동학적 차이를 분석하여 낙상예방을 위한 기초자료를 제공하는데 있다. 이를 위해 70대 이상 80세 이하의 여성 고령자 7명을 선정하여 3차원 영상분석을 실시하였다. 하지 분절과 관절의 3차원 위치좌표를 얻기 위해 ProReflex MCU(Qualisys, Sweden) 카메라를 사용하여, 100Hz/s로 촬영하였다. 촬영된 영상은 QTM(Qualisys, Sweden) 프로그램을 이용하여 위치좌표에 대한 원자료(raw data)를 얻었으며, Matlab 6.5 프로그램을 이용하여 3차원 각도를 산출한 결과, 다음과 같은 결론을 얻었다. 대퇴와 하퇴분절의 굴곡과 신전은 E5에서 운동 후 굴곡의 움직임이 크게 나타났으며, 발 분절은 E4에서 외번을 보이면서 통계적 차이를 나타냈다. 무릎관절은 운동 후 E4에서 굴곡을 보였고, 발목관절은 E3에서 내번, E4에서 외번의 움직임을 나타내면서 통계적인 차이(p<.05)를 보였다.

• 한국운동역학회지
• /
• 제17권2호
• /
• pp.61-73
• /
• 2007

The purpose of this study was to investigate the influence of the muscular endurance on the kinematic factors during a prolonged run. Subjects, 12 males, who were divided into three groups(lower group, general group, and in higher group) after measuring the lower limb's muscular endurance previously. They were asked toe run on the treadmill at 7.4km/h of speed. To analyze the kinematics parameters of the trunk during running, the ProReflex MCU Camera(Qualisys, Sweden) were used. All parameters were sampled from 5 minute, 40 minute, and 60 minute moments during running. An ANOVA with Repeated Measure was used to test the statistic significance between and within groups for all parameters determined with SPSS 11.0. Significance was defined as p<.05. The conclusions were as follows; There was significantly difference within(lapse of running time) groups in the take-off and minimum knee angle event of swing phase of the trunk flexion and extension. In conclusion, the muscular endurance affected on movement of the trunk during a prolonged run. In addition, it showed that there was significant difference in the energy consumption by lapse of running time. Therefore, it seems to be relationships between the muscular endurance and running efficiency.

• 한국운동역학회지
• /
• 제26권1호
• /
• pp.51-69
• /
• 2016

Objective: The purpose of this study is to suggest new terminology for the ninety-five hand techniques based on the significance of their angular momentum, determined by analyzing each technique's influence or impact on the compartmentalized angular momentum of the trunk, upper arm, and forearm in the Taekwondo Poomsae. Method: An athlete who won the 2014 World Taekwondo Poomsae championship was selected and agreed to participate in the data collection phase of our investigation. The video data was collected using eight infrared cameras (Oqus 300, Qualysis, Sweden) and the Qualisys Track Manager software (Qualisys, Sweden). The angular momentum of each movement was then calculated using the Matlab R2009a software (The Mathworks, Inc., USA). Results: The classification of the ninety-five hand techniques in the Taekwondo Poomsae based on the significance of each segment's momentum is as follows. Makgi (blocking) is classified into fourteen categories, jireugi (punching) is classified into three categories, chigi (hitting) was classified into six categories, palgupchigi (elbow hitting) was classified into four categories, and jjireugi (thrusting) was classified two categories. Conclusion: This study offers a new approach, based on a biomechanical method, to the classification of the hand techniques that reflect kinesthetic motions in the Taekwondo Poomsae.

• 한국운동역학회지
• /
• 제16권2호
• /
• pp.21-24
• /
• 2006

The purpose of this paper is to diagnose the errors by comparing putting motion with the single pendulum pattern applicable to putting in golf skill and order prescription that correct errors of putting. In the modern-day game of golf, putting remains the key to shooting low scores, and the ability to hole putts can turn a good round into a great round A semi-golfer, subject(sex female, age 20yrs, mass 94.3kg, height 1.65m) who has troubles to do putting is chosen. Six cameras, ProReflex MCU240(240Hz) made by Qualisys company is used to capture putting motion and data is processed by QTM(Qualisys Track Manager) and Mathematica 5.0. The result that differentiates the putting and the single pendulum pattern is acquired To make the pattern of subject's putting to the single pendulum pattern quasi-equal, one tries to lower center of mass gradually. As a result of it, one has a similar pattern like the single pendulum Conclusively, to lower C.O.M one orders prescriptions that increase the weight and length of a putter and lower C.O.M subject's segment. Further improvements to the study could be to train a subject according to prescriptions and to monitor putting again. It will probably be necessary to simulate putting motions and to research relations for body shapes and putting patterns in order to establish suitable putting-motions.

• 대한안전경영과학회지
• /
• 제12권4호
• /
• pp.81-86
• /
• 2010

Despite the importance of cycling postures during cycling performances, there has been a very little research investigating cycling postures and pedaling rate for particularly concerning domestic cyclists. The aim of this study was to analyze correlations and effects between cycling postures and pedaling rate in track cycling. Twelve male racing cyclists (six racing and university cyclists) participated in this research. For this study, seven infrared cameras (Qualisys ProReflex MCU-240s) were used for collecting data and these were processed via QTM (Qualisys Tracker Manager) software. It appeared that pedaling rate had correlations with regard to a shoulder angle (R=-.601) and displacement between shoulder joints(R= -.637), but a knee (R=-.601) and ankle angle (R=.667). Moreover, two multiple regression equations of pedaling rate for cycling postures were significant and R2 of the first order equation y (pedaling rate) = 0.039x (knee angle) - 1.068 was less than the second order equation y = 0.006x2 - 1.287x + 69.674. In conclusion, cycling postures affected the pedaling rate. Further study should be researched on postures in relation to air resistance in a wind tunnel.

• 한국콘텐츠학회논문지
• /
• 제7권4호
• /
• pp.234-240
• /
• 2007

이 연구는 철봉 몸굽혀 휘돌기 동작의 최적 모델을 구축하는 것이다. 연구 대상자는 국가대표 남자체조선수(나이 18세, 신장 153cm, 질량 48kg) 1명을 선정하였고, K대학교 체조장에 기 설치된 Spieth사의 철봉을 이용하여 실험하였다. 먼저 대상자에게 연구의 목적과 주의 사항을 주지시키고 사전 서면동의를 받은 후 실험을 실시하였다. 인체를 2분절로 모형화한 몸 굽혀 휘돌기 동작의 영상분석을 위하여 Qualisys사의 카메라(MCU-240) 6대와 소프트웨어인 QTM(Qualisys Track Mannager)을 사용하였다. 이 동작을 이중진자(HAT/total leg)로 모형화하고 라그랑지 운동방정식의 파라메터에 실험에서 획득한 수치를 입력하여 시뮬레이션하였다. 데이터 처리와 모델(미분 연립 방정식)의 해는 Mathematicas5.0으로 프로그래밍하여 구하였다. 분석변인에 대한 모델치와 실험치의 비교 결과는 첫째, 철봉의 최대변위는 모델치(약 0.18 m)가 실험치(약 0.16 m)보다 약 0.02m 더 크게 나타났다. 둘째, 분절1(HAT)의 각변위 패턴은 모두 증가곡선을 보였으나 변곡점의 차이가 나타났다. 셋째, 분절2(total leg)의 각변위 패턴은 전반적으로 유사하게 나타났으나 최대 각은 약 $4^{\circ}$ 차이를 보였다. 결론적으로 실험치와 일치하는 최적모델을 도출하지는 못하였지만 라그랑지 모델을 통한 시뮬레이션의 가능성을 제시하였다. 향후 제한된 2분절 모형을 3, 4분절 모델로 확장하고 생체물성(근골격계)을 정확하게 표현하는 물리적 도구를 개발하는 연구와 인체시스템을 근골격계와 근신경계을 통합한 모델구축이 이루어져야 하겠다.

• 한국운동역학회지
• /
• 제15권3호
• /
• pp.143-152
• /
• 2005

The purpose of this study was to predict the failure or success of the Snatch-lifting trial as a consequence of the stand-up phase simulated in Kane's equation of motion that was effective for the dynamic analysis of multi-segment. This experiment was a case study in which one male athlete (age: 23yrs, height: 154.4cm, weight: 64.5kg) from K University was selected The system of a simulation included a multi-segment system that had one degree of freedom and one generalized coordinate for the shank segment angle. The reference frame was fixed by the Nonlinear Trans formation (NLT) method in order to set up a fixed Cartesian coordinate system in space. A weightlifter lifted a 90kg-barbell that was 75% of subject's maximum lifting capability (120kg). For this study, six cameras (Qualisys Proreflex MCU240s) and two force-plates (Kistler 9286AAs) were used for collecting data. The motion tracks of 11 land markers were attached on the major joints of the body and barbell. The sampling rates of cameras and force-plates were set up 100Hz and 1000Hz, respectively. Data were processed via the Qualisys Track manager (QTM) software. Landmark positions and force-plate amplitudes were simultaneously integrated by Qualisys system The coordinate data were filtered using a fourth-order Butterworth low pass filtering with an estimated optimum cut-off frequency of 9Hz calculated with Andrew & Yu's formula. The input data of the model were derived from experimental data processed in Matlab6.5 and the solution of a model made in Kane's method was solved in Matematica5.0. The conclusions were as follows; 1. The torque motor of the shank with 246Nm from this experiment could lift a maximum barbell weight (158.98kg) which was about 246 times as much as subject's body weight (64.5kg). 2. The torque motor with 166.5 Nm, simulated by angular displacement of the shank matched to the experimental result, could lift a maximum barbell weight (90kg) which was about 1.4 times as much as subject's body weight (64.5kg). 3. Comparing subject's maximum barbell weight (120kg) with a modeling maximum barbell weight (155.51kg) and with an experimental maximum barbell weight (90kg), the differences between these were about +35.7kg and -30kg. These results strongly suggest that if the maximum barbell weight is decided, coaches will be able to provide further knowledge and information to weightlifters for the performance improvement and then prevent injuries from training of weightlifters. It hopes to apply Kane's method to other sports skill as well as weightlifting to simulate its motion in the future study.

• 한국운동역학회지
• /
• 제31권4호
• /
• pp.241-248
• /
• 2021

Objective: The purpose of this study was to investigate the difference in muscle strength, kinematics, and kinetics between injured and non-injured sides of the leg after Achilles Tendon Rupture surgery during walking and running. Method: The subjects (n=11; age = 30.63 ± 5.69 yrs; height = 172.00 ± 4.47 cm; mass = 77.00 ± 11.34 kg; time lapse from surgery = 29.81 ± 10.27 months) who experienced Achilles Tendon Rupture (ATR) surgery participated in this study. The walking and running trials were collected using infrared cameras (Oqus 300, Qualisys, Sweden, 100 Hz) on instrumented treadmill (Bertec, U.S.A., 1,000 Hz) and analyzed by using QTM (Qualisys Track Manager Ver. 2.15; Qualisys, U.S.A). The measured data were processed using Visual 3D (C-motion Inc., U.S.A.). The cutoff frequencies were set as 6 Hz and 12 Hz for walking and running kinematics respectively, while 100 Hz was used for force plate data. Results: In ATR group, muscle strength there were no difference between affected and unaffected sides (p> .05). In kinematic analysis, subjects showed greater ROM of knee joint flexion-extension in affected side compared to that of unaffected side during walking while smaller ROM of ankle dorsi-plantar and peak knee flexion were observed during running (p< .05). In kinetic analysis, subjects showed lower knee extension moment (running at 2.2 m/s) and positive ankle plantar-flexion power (running at 2.2 m/s, 3.3 m/s) in affected side compared to that of unaffected side (p< .05). This lower positive ankle joint power during a propulsive phase of running is related to slower ankle joint velocity in affected side of the subjects (p< .05). Conclusion: This study aimed to investigate the functional evaluation of the individuals after Achilles tendon rupture surgery through biomechanical analysis during walking and running trials. Based on the findings, greater reduction in dynamic joint function (i.e. lower positive ankle joint power) was found in the affected side of the leg compared to the unaffected side during running while there were no meaningful differences in ankle muscle strength and walking biomechanics. Therefore, before returning to daily life and sports activities, biomechanical analysis using more dynamic movements such as running and jumping trials followed by current clinical evaluations would be helpful in preventing Achilles tendon re-rupture or secondary injury.

• 한국운동역학회지
• /
• 제14권3호
• /
• pp.1-15
• /
• 2004

The purpose of this study was to investigate the kinematic variables of the upper part of the body for 8 elderly men during walking. For this study, kinematic data were collected using a six-camera (240Hz) Qualisys ProReflex system. The room coordinate system was right-handed and fixed in space, with righted orthogonal segment coordinate systems defined for the head, trunk, and pelvis. Based on a rigid body model, reflective marker triads were attached on the 3 segments. Three-dimensional Cartesian coordinates for each marker were determined at the time of recording using a nonlinear transformation(NLT) technique with ProReflex software (Qualisys, Inc.). Coordinate data were low-pass filtered using a fourth-order Butterworth with cutoff frequency of 6Hz. Three-dimensional angles of the head, trunk, and pelvis segment were determined using a Cardan method. On the basis of each segment angle, angle-angle plot used to estimated the movement coordinations between segments. The conclusions were as follows; (1) During the support phase of walking, the elderly people generally kept their, head the flexional and abductional posture. Particularly, the elderly displayed little internal/external rotation. (2) The elderly people showed extensional and external rotation postures in the trunk movement. Particularly, It showed the change from adduction into abduction at the heel contact event of the stance phase. (3) The elderly people showed almost same pelvis movement from the flexion into extension, from the abduction into adduction, and from internal rotation into external rotation at the mid stance and toe off of the stance phase.

• 한국운동역학회지
• /
• 제26권2호
• /
• pp.221-228
• /
• 2016

Objective: The purpose of this study was to investigate differences in gait parameters and symmetry between walking speed by using the Froude number and preferred walking speed. Method: Fifty adults (age: $21.0{\pm}1.7years$, body weight: $71.0{\pm}9.2kg$, height: $1.75{\pm}0.07m$, leg length: $0.89{\pm}0.05m$) participated in this study. Leg length-applied walking speed was calculated by using the Froude number, defined as Fr = ${\upsilon}^2$/gL, where v is the velocity, g is the gravitational acceleration, and L is the leg length. Video data were collected by using eight infrared cameras (Oqus 300, Qualysis, Sweden) and the Qualisys Track Manager software (Qualisys, Sweden), with a 200-Hz sampling frequency during two-speed walking (preferred walking speed [PS] and leg length-applied walking speed [LS]) on a treadmill (Instrumented Treadmill, Bertec, USA). The step length, stride length, support percentage, cadence, lower joint angle, range of motion (ROM), and symmetry index were then calculated by using the Matlab R2009a software. Results: Step and stride lengths were greater in LS than in PS (p < 0.05). The right single-support percentage was greater in LS than in PS (p < 0.05). The hip joint angle at heel contact and toe-off were greater in LS than in PS (p < 0.05). The hip and knee joint ROM were greater in LS than in PS (p < 0.05). Conclusion: Based on our findings, we suggest that increased walking speed had a significant effect on step length, stride length, support percentage, and lower joint ROM.