Simulation study to elucidate the mechanism of ollie jump in skateboarding

抄録

In skateboarding as a sports event, the riders compete in difficulty and completeness of acrobatic motions called “tricks”. As a basic trick, Ollie is performed popularly. However, the basic mechanical principle of the Ollie has not been discussed to date, especially for the Ollie jump (the jumping phase of Ollie). The objective of this study was to elucidate the mechanism of Ollie jump in skateboarding. A simulation model was firstly constructed on a multibody dynamics analysis platform. Next, an experiment using an actual rider was conducted to acquire the motion of the feet during the Ollie jump. By inputting the acquired motion of the feet into the model, a simulation of Ollie jump was carried out. In addition, a parameter study with respect to the geometry of the skateboard and the motion of the rider’s feet was conducted. It was found that the simulated Ollie jump was successful since the skateboard reached a sufficient height and became sufficiently horizontal at the peak height. It was also found that the Ollie jump can be divided into five stages from the mechanical point of view. From the parameter study, it was found that large kick angle of the deck or large distance between two trucks of the deck might cause difficulty in the contact of the tail and the ground, while small kick angle or small distance between two trucks might result in excessive rotating angle of the deck. In addition, three important points for a successful Ollie jump were found to be, to produce sufficiently fast rotational movement of the skateboard around the rear wheels, to separate both feet from the deck before the tail of the deck hits the ground, and to separate the rear foot from the deck at the final stage.