APPLICATION OF COMPARATIVE METHOD FOR KINEMATICSANALYSIS OF MOVING ACTIVITIES

  • Frantisek Zahalka

Abstract

INTRODUCTION - It is possible to describe movement of the body with the basic physical issue like is time, trajectory and velocity. One of the possibilities how to characterize this issue is application of kinematics analysis. The analysis is achieved from video record with adding plane coordinates of important points or segments. Kinematics analysis based on the computer processed videorecords offers big amount of useful information like is trajectory in individual axes or planes, velocity of the points, or angles of the whole segments. All this information is useful only after a proper selection and after processing into the interpretation form. There is necessary to look for the mutual relations between the stimulation ( for example training ) and the moving structure which is influenced with this stimulation. These relations can influence the movement by itself, training of the movement and also it's cultivation. Therefore we must use this method, which can create a model allowing comparation of chosen variables ( real movement - ideal model situation ). Principe of this method is an mtegration of the time axis towards the inportant point of the movement activity. It can be for example the moment when the legs are leaving the floor, or when the , hands are leaving the equipment. With the I repeating comparison we can see the same and the different trajectories or ver locities of individual segments. Used I equipment is Consport Motion Analyzator which is based on the similar principle as motion analyzator APAS. This equipment used video system PAL ( 25 frameslsec ) , and computer system PC. RESULTS - Method of comparative kinematics analysis is based on comparison of measurable results of moving activity. We can compare good or wrong attempt visually during the exercising or later from video record, but there isn't already necessary to make complicated kinematics analysis. If we value the attempts which are qualitatively comparable an expert can already see the basic differences; but without mutual relations. Visual comparison is immediate but kinematics analysis allowed to save all obtained information and later to use them for comparison. To look for the wider connections of causes of movement exercise is sensible only in the area of moving exercises which are possible to qualify as better or worst attempts. Therefore the principle problem for application of this method is the choice of suitable dates. We have to record for every subject at least twice concrete movement activity and then we can use it as "individual model". Only then it is possible to compare these 'models" between each other and to reveal differences. Also it is necessary to unite all these activities in the same moment which is for this movement for many reasons decisive. This method is used mainly at the branch of sports gymnastics especially for processing of results from the European championship. CONCLUSION - By the comparing we are able to appoint different style of a performance or we can find mistakes during the moving exercise. It is possible to create an individual model of every exercise and to use this model to compare intra-individual characteristics of moving activity.
Section
Equipment / Instrumentation