Volume 9, No. 1
Relationship between jump length and the position angle in ski jumping
Razmerje med dolžino skoka in kotom skakalca pri smučarskih skokih
Abstract (English)
Using a simple physical model of ski jumping the current study investigates the relationship between a ski jumper's position angle during the flight phase and the jump length as well as other physics variables. The physical parameters of the jump (velocity, current drag, jump length) were calculated taking into account height of the jumping hill, inclination of the outrun, and position of the system jumper-skis during the flight phase. The analysis of the jump curve was made on the basis of the angle between the flight trajectory of the common centre of gravity and the x-axis (?). For the analysis of the jumper’s position during the flight phase the angle between the upper part of the body and the flight trajectory of the common centre of gravity of the body (() was chosen. In the computer simulation of the jump length two variants of the course of the angle ( were used. The flight velocity was very similar in both variants. Immediately after take-off, the resultant velocity v(t) and its horizontal component vx(t) slightly decreased. After that the resultant velocity increased constantly due to the constant increase in the vertical component vy(t). Due to the current drag the horizontal flight component vx(t) decreased constantly during the entire flight phase. The current drag FD(t) and lift components FL(t) rose to a greater extent in the changeable ski jumper’s position angle (.
Keywords (English)
ski jumping, physical model, computer simulation, position angle
Abstract (Slovenian)
Cilj raziskave je bil z enostavnim fizikalnim modelom smučarskega skoka ugotoviti povezanost med skakalčevim kotom med fazo leta in dolžino skoka ter nekaterimi drugimi fizikalnimi parametri. Fizikalni parametri skoka (hitrost, sila upora, dolžina skoka) so bili izračunani z upoštevanjem višine skakalnice, nagiba pristajalnega dela skakalnice in pozicije sistemska skakalec - smuči med fazo leta. Analiza krivulje skoka je bila narejena na osnovi kota med linijo leta glede na skupno težišče in x-osjo (?). Za analizo pozicije skakalca med letom je bil izbran kot med zgornjim delom telesa in linijo leta glede na skupno težišče telesa (?). V računalniški simulaciji dolžine skoka smo uporabili dve varianti kota ?. Hitrost leta je bila je bila v obeh različicah podobna. Takoj po vzletu sta se hitrost v(t) in njena horizontalna komponenta vx(t) nekoliko zmanjšali. Temu sledi stalno naraščanje hitrosti, ki gre na račun stalnega povečevanja njene vertikalne komponente vy(t). Horizontalna komponenta leta vx(t) je zaradi sile upora skozi celoten let stalno upadala. Komponenti sil upora FD(t) in dviga FL(t) s spreminjanjem kota pozicije skakalca ??narašč
Keywords (Slovenian)
smučarski skoki, fizikalen model, računalniška simulacija, kot skakalca
