Dynamic modelling of jump spinning and twisting in sport.

Dynamic modelling of jump spinning and twisting in sport. The study that has been addressed consists in the understanding and modeling of twists and rotations applied at a sporting level in certain fields. In particular, due to the complexity and completeness of the case, in the following paper the movement of a taekwondo athlete to perform a 540 ° hook kick was observed and through the comparison with what happens in other sports and in other fields, the mechanics are explained. This was done through the analysis of both the take-off part and the flight phase. During this analysis, a fundamental factor was found in the link with the conservation law of the angular momentum for both phases. The exploitation of this law, through the movement of the limbs by the performer, allows us to perform certain exercises that would otherwise be impossible. In particular, in the take-off phase these movements will generate reactions from the ground (point of contact), while, in the flight phase, they will give rise to a reorientation of the body in mid-air. Once the mechanics behind the exercise were explained, an analytical model was built to calculate the momentum momentum produced by the athlete's movement (momentum variation generated internally), and a physical model that simulated everything. After having validated the physical model, it was compared with the analytical one, finding a certain consistency. The modeling phase was followed by an analysis and implementation phase where a method was sought to improve the execution of the exercise through the use of an external mechanism. Once a point on which to act to obtain tangible results was found and to have a certain generalization of the phenomenon, several simulations were performed through the use of the physical model. The idea was to use a mechanism that applied an additional internal torque, generated at the most opportune moment, in order to increase the angular momentum at the take-off and generate more reactions from the ground, giving the athlete greater speed and time to exploit. In the simulations certain conditions were varied to see how the model behaved and to evaluate if the results were positive and the presence of an optimum point. The results of the implementation were successful leading to the generation of a greater moment of momentum in the take-off phase.