Design and Implementation of a Digital Videogrammetry System Applied to Jumping Sportsmen Analysis

Abstract

This paper presents the design and implementation of a system for kinematic and kinetic analysis of vertical jump. The system is based on the use of techniques of videogrammetry and digital image processing to register the sequence of the movement executed. An application program for the registering and processing of data obtained through the camera, using the tools of digital image processing and the user interface GUI offered by Matlab, was designed and developed. A bidimensional biomechanical model of the lower limbs is available by the program, which, from five referenced anatomical points, determines the values of distance, speed, acceleration, strength, power and joint angles of the lower limbs, along the implementation of jump. There were pilot tests carried out with five subjects using a vertical jump protocol, in order to compare the curves delivered by the software with the curves which were found theoretically in the literature and obtained data by another measurement system. In spite of the limitations of the system related to the analysis of two-dimensional vertical jump, it was possible to obtain satisfactory results with reference to other methods currently used and to specific measuring equipment.