Yeadon M R, Hiley M J
School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough LE11 3TU, UK.
School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough LE11 3TU, UK.
J Biomech. 2017 Jun 14;58:174-178. doi: 10.1016/j.jbiomech.2017.05.002. Epub 2017 May 16.
An angle-driven computer simulation model of aerial movement was used to determine the maximum amount of twist that could be produced in the second somersault of a double somersault on trampoline using asymmetrical movements of the arms and hips. Lower bounds were placed on the durations of arm and hip angle changes based on performances of a world trampoline champion whose inertia parameters were used in the simulations. The limiting movements were identified as the largest possible odd number of half twists for forward somersaulting takeoffs and even number of half twists for backward takeoffs. Simulations of these two limiting movements were found using simulated annealing optimisation to produce the required amounts of somersault, tilt and twist at landing after a flight time of 2.0s. Additional optimisations were then run to seek solutions with the arms less adducted during the twisting phase. It was found that 3½ twists could be produced in the second somersault of a forward piked double somersault with arms abducted 8° from full adduction during the twisting phase and that three twists could be produced in the second somersault of a backward straight double somersault with arms fully adducted to the body. These two movements are at the limits of performance for elite trampolinists.
使用一个角度驱动的空中运动计算机模拟模型，来确定在蹦床上进行双体前空翻的第二个空翻时，通过手臂和臀部的不对称运动能够产生的最大扭转量。基于一位世界蹦床冠军的表现，对手臂和臀部角度变化的持续时间设定了下限，该冠军的惯性参数用于模拟。对于向前空翻起跳，极限动作被确定为尽可能大的奇数个半扭转；对于向后起跳，则为偶数个半扭转。通过模拟退火优化找到这两种极限动作的模拟结果，以在飞行2.0秒后着陆时产生所需的空翻、倾斜和扭转量。然后进行额外的优化，以寻求在扭转阶段手臂内收较少的解决方案。结果发现，在前空翻屈体双体空翻的第二个空翻中，当扭转阶段手臂从完全内收外展8°时，可以产生3.5个扭转；在向后直体双体空翻的第二个空翻中，当手臂完全内收至身体时，可以产生三个扭转。这两种动作处于精英蹦床运动员的表现极限。
