• 전기학회논문지
• /
• 제56권2호
• /
• pp.374-382
• /
• 2007

Robot mobility and intelligence become more important for robots to be used in various fields other than automation. The main purpose of providing mobility to a robot is to extend the robot's manipulability. In this paper, we introduce a small humanoid robot that can autonomously play golf as an example of incorporating robot intelligence, mobility, and manipulability. The robot has 12 degrees of freedom for legs and has various basic walking patterns. It can move to a desired position and change orientation by combining the basic waking patterns. The robot has a color CCD camera and can extract coordinates of the objects in the environments. The small humanoid robot has 8 degrees of freedom for arms and can play golf autonomously with two kinds of dexterous swing motions. Kinematic analysis of the robot arms, vision data processing for the recognition of the environments, algorithm for playing robotic golf have been performed or proposed. The experimental results show that the robot can play golf autonomously.

• 한국운동역학회지
• /
• 제22권1호
• /
• pp.75-82
• /
• 2012

The purpose of this study was to suggest the proper shaft and head fitting methods of the golf club to increase the flight distance of the golf ball. Rotations per minute of the golf ball(RPM), ratio of Ball speed to club head speed(T-Ratio) and launch angle right after impact(LA), which are directly related to ball flight distance, were measured using Spectra with shutter speed of 1/1000sec at the constant head speed of 95mph which was controlled by robot golf swing machine. In order to investigate the effect of club shaft to the 3 selected variables, 10 shafts were used to make ten test clubs with one controlled club head which is the most commonly used by golf players. To measure the effect of the club head to the 3 selected variables, 6 golf club heads which are most commonly used by golfers were selected to make 6 test clubs with a controlled shaft which is one of the best known by players. The shafts and the heads were identified by statistical analysis to increase or decrease the RPM, T-ratio and LA. A proper fitting method of the selected shafts and the club head was suggested to increase the ball flight distance in golf.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2005년도 춘계학술대회 논문집
• /
• pp.2011-2014
• /
• 2005

The purpose of this study is to compare the modal parameters of a newly developed soft golf club prototype, which is designed to be lighter than regular golf clubs, with those of a regular commercial golf club. The modal tests were performed with two kinds of boundary conditions. The first condition was free-free condition and the second was fixed-free condition. An impact hammer and a Fast Fourier Transform analyzer were used to obtain modal data. From the results, it was found out that the modal characteristics of the soft golf club prototype were close to those of the regular golf club although the weight of the soft club was lighter. Therefore, the soft golf club is expected to be able to convey similar feel to the golfers even with lighter weight. This would enable elderly golfers to swing easily with the soft golf club with same skill which they acquired with regular golf clubs but with reduced load to their muscles.

• 한국운동역학회지
• /
• 제20권4호
• /
• pp.487-495
• /
• 2010

The purpose of this study was conducted to make a comparative biomechanical analysis of X-factor and X-factor stretch during driver and iron swing. The subjects were composed of 10 professional golfers with more than 10 years career. The result was as follows: First, the analysis of the back swing with driver and iron swing showed no differences statistically between both the timing in horizontal rotating of shoulder and hip, the time required for X-factor stretch also showed no differences statistically. Second, the back swing with a driver swing showed more maximum horizontal rotation of shoulder and hip joint than the back swing with an iron swing, but the twist of shoulder and hip that was X-factor stretch angle showed no difference. Third, the GRF of the max value for the left and right foot during shoulder and hip horizontal rotation of back swing showed no differences statistically in the movement of driver and iron swing during the back swing, and the GRF of X-factor stretch for the left and right foot showed no differences statistically in driver and iron swing. Therefore the result of this research showed that the operation of torso(X-factor stretch) and weight shifting were similar although the horizontal rotation of body was different during the driver and iron swing.

• 대한정형외과스포츠의학회지
• /
• 제3권1호
• /
• pp.15-21
• /
• 2004

Golf has become an increasingly a popular sports for young and older ages. It has benefits of walking exercise and enjoyment of sports . However, golf is considered to be a moderate risk activity for sports injury due to traumatic origin and overuse. Golf injuries primarily affect the dorsolumbar sites , upper extremity(elbow, shoulder, wrist) and lower extremity (knee, hip, ankle). Ajustment of golf swing and conditioning programmes for preventing injuries which include muscular strengthening, flexibility and a short pregame warm up help to reduce the incidence of injury.

• 한국운동역학회지
• /
• 제21권4호
• /
• pp.411-420
• /
• 2011

The purpose of this investigation was to determine whether correlations exist between balance and impact velocity, angular position, and maximum velocity of a club during drive swing. Twelve skilled golfers were recruited in this study. They were asked to perform ten swing trials and two trials were selected for analysis. Balance parameters were calculated via the force platform while kinematic variables were determined by using the Qualisys system. The results of the present study demonstrated that the average of COP velocity was faster in the medio-lateral direction rather than the anterio-posterior direction. Also, left foot's COP velocity and free torque were greater than the right foot's before impact. The range of the right foot's COP in the anterio-posterior direction before impact were correlated with the club velocity and angular position at impact. There was a negative correlation between the left foot's COP velocity before the impact and the velocity at impact. Additionally, the range and RMS of the left foot's free torque affected on the club angular position at impact and the maximum velocity at release, respectively. Finally, a negative correlation existed between the range of the right foot's free torque after the impact and club's maximum velocity at release.

• 한국운동역학회지
• /
• 제15권4호
• /
• pp.97-104
• /
• 2005

Previous studies of kinematic analysis of golf swing usually dealt with variations vertically. The purpose of the study was to examine the horizontal hip joints motion of the fifteen male professional golfers during driver swinging. Kinematic variables were calculated by the Kwon3D motion analysis program. Paired t-tests and one-way ANOVA were used to compare the hip height, distance, displacement, and position differences. Results showed that there were no hip height changes and no hip height differences between left and right hip from address to impact. The axis of the backswing was braced right hip, the axis of the downswing was moving left hip. Hips position at the top of the backswing showed that hips move to target prior to hands, which means the sequential motion of the chain linked body segments. From address to impact, left hip moving distance was longer than right hip(p<.001), but during the whole swing, right hip moving distance was longer than left hip(p<.001). Hip rotation angle to target line was $-48.14{\pm}9.32^{\circ}$ at top of the backswing, $40.88{\pm}8.44^{\circ}$ at impact, and $104.70{\pm}8.14^{\circ}$ at finish.

• The Journal of Korean Physical Therapy
• /
• 제34권4호
• /
• pp.149-154
• /
• 2022

Purpose: The purpose of this study was to investigate effects of the modified bent arm tornado exercise on weight shift movement and muscle activity of the impact section in the top of the drive swing. Methods: Twenty subjects were divided professional golfer group and amateur golf group. Subjects were required to complete following modified bent arm tornado exercise. The activity and weight shift of the gluteus group and lower extremity muscles between the two groups were measured and the Wilcoxon rank test was analyzed. Results: The distribution of weight shift in the professional golfer group was higher than that of the amateur golfer group (p<0.05). During the golf downswing of the professional golfer group, muscle activation of the lower extremities was higher than that of the amateur golfer group (p<0.05). The distribution of weight shift after exercise by the amateur golfer group was higher than before (p<0.05). Conclusion: We could confirm was increased significantly of muscle activity and weight shift by applying modified bent arm tornado exercise through this study. This result suggests that exercise is needed to improve weight shift.

• 한국운동역학회지
• /
• 제19권2호
• /
• pp.273-286
• /
• 2009

본 연구는 고등학교 여자선수들을 대상으로 3차원 영상분석을 이용하여 스윙시 나타나는 각 신체분절 및 클럽의 직임을 운동학적 및 운동역학적 변인들을 산출하여 성공과 실패시에 대한 중요변인들을 비교 분석함으로써 정량적 자료의 추출과 더불어 정성적 평가를 하는데 목적이 있다. 운동학적 변인으로써 위치변화, 속도, 각도에 대한 3차원 분석과 지면반력에 대한 분석을 하였다. 그 결과 스윙시 클럽헤드는 어드레스와 톱스윙시 전후 이동(X축)이 매우 적게 나타남으로써 안정적 스윙이 유지 되는 것으로 나타났다. 또한 좌우방향(Y)의 신체중심이동속도는 성공적인 스윙 동작 시 실패동작시보다 임팩트시 매우 빠른 속도를 나타냄으로써 운동량 증가에 많은 기여를 하였으며 코킹각은 톱스윙에서부터 임팩트까지의 성공시가 코킹각을 더 크게 풀어 줌으로써 임팩트시 선속도 증가에 영향을 주어 비거리 증가에 유리하게 작용할 것으로 판단된다. 지면반력(GRF)은 전후방(X축)과 좌우방향(Y축)에서 안정적인 지지율로 나타남으로써 성공적 스윙으로 연결된 것으로 나타났다.

• 한국운동역학회지
• /
• 제12권2호
• /
• pp.259-278
• /
• 2002

본 연구에서는 볼 구질의 변화에 따른 스윙 동작의 운동학적인 변인을 3차원적으로 비교 분석하여 스윙 동작의 운동역학적인 원리를 제시하며, 볼 구질이 다른 스윙 동작의 차이점을 밝히는 데 목적이 있으며, 프로골퍼로 경력 3년 이상의 남자 선수 7명을 대상으로 스트레이트 성공, 페이드 성공과 실패로 구분하여 골프 스윙의 운동학적 변인들을 과학적으로 제시하기 위해 비교 분석한 결과 다음과 같은 결론을 얻었다. 페이드 성공시에는 임팩트를 지나서도 계속 손목의 각도가 근소한 차이로 줄어드는 것으로 나타났고 실패시에는 각 프레임의 각도가 규칙적으로 변하지 않게 나타났다. 이는 스트레이트 성공과 페이드 성공에 대한 손목각도의 차이가 영향을 미치는 것으로 나타나 다른 요인과 손목각도와의 관계를 분석하는 것이 필요하다고 하겠다. 페이드 실패의 경우는 임팩트시의 몸통 비틀림각도가 성공때 보다 작아지면서 클럽헤드가 오픈되지 못한 것으로 나타났다. 골프스윙의 형태의 변화로 인하여 어깨관절의 회전력을 더 많이 사용하여 파워을 증진시키기 위한 동작이며, 골프 스윙에서 어깨회전 운동은 축을 중심으로 회전하기 때문에 어깨회전각도의 차이는 없는 것으로 나타났다. 스트레이트 성공시 보다 페이드 성공시에 고관절의 회전각도가 점진적으로 일정하게 각이 커졌다. 이는 고관절의 회전을 더 크게 하여 지연히팅을 보다 자연스럽게 한 것으로 나타났다. 페이드 볼 구사시 임팩트 존에서 클럽의 페이스가 닫히는 것과 팔의 자연스러운 롤링 동작을 억제시키는 것으로 나타났다. 본 연구에서는 구질 변화에 따른 골프 스윙 동작을 스트레이트 성공, 페이드 성공과 실패시로 구분하여 운동학적 변인들을 3차원 동작 분석을 통하여 경기력 향사에 도움이 되고자 하였으며 앞으로 많은 연구자들이 각 종목에 있어서 경기력 향상을 위한 역학적인 분석이 계속 진행되어져야 할 것이다.