High Speed Motion Tracking for Weightlifting based on Correlation Coefficient Template Matching
Gihan Kuruppu, Saluka Ranasinghe Kodituwakku, U.A.J. Pinidiyaarachchi · 2013
Tracking of motion in weightlifting is a challenging task. This paper presents a method for tracking Weightlifting bar movement of an athlete. The proposed method uses three different template creation techniques for tracking and applies Wilcoxon Signed rank test to evaluate the results. The method was tested with normally captured data (30fps) and data captured in slow motion (100fps) separately. For the normally captured data, combined dynamic templates method has the highest accuracy of 95% in tracking the trajectory. For slow motion data Wilcoxon Signed Rank generated equal results for all three template creation methods. A sport is a competitive physical activity which contributes to the improvement of physical, social and psychological aspects of life. It also gives entertainment to the participants. Competitiveness of sports is ever increasing and every professional athlete's ultimate aim is winning an international medal like an Olympic gold medal. Therefore, athletes try to improve their techniques in order achieve this goal. Developed countries spend large amounts of money to develop their athlete's techniques. On the contrary, developing countries such as Sri Lanka cannot spend that much of money to improve sports techniques. Therefore such countries need low cost new technologies as an alternative. The invention of computers has greatly modernized and improved the world of athletics. Computer technology allows for increased accuracy in different sporting events and can be used to correct athlete's bio-mechanics techniques which are difficult to evaluate using naked eye. Weightlifting is a power sport that is carried out in less than one minute and the athletes need highly accurate technique for reaching their targets. The two competition lifts in order are the and the Clean and Jerk. This research work mainly concentrates on the snatch. The Snatch requires the dragging of the bar from the bottom to top in 6 phases (1). Main 3 phases are depicted in Figure 1. Bar moving trajectory and other variant features such as bar travelling distance and velocity can track athlete's technical errors(2)(3)(4).