両大腿切断スイマーのための自由形アームストロークの最適化シミュレーション

抄録

For the competitive swimmers with physical disability, the optimized stroke of crawl swimming has not been clarified yet, and may be different from that of able-bodied swimmers. The objectives of this study was to solve computationally the arm stroke of the crawl swimming that maximized the swimming speed for swimmers with bilateral transfemoral amputation, and to investigate the features of the optimized stroke. The optimized stroke was obtained by the optimization method with Particle Swarm Optimization (PSO) algorithm and the swimming human simulation model. In this method, the design variables were the upper limb joint angles, represented by five degrees-of-freedom (three at the shoulder joint and two at the elbow joint), and the fastest stroke was obtained as the optimized stroke. When the stroke cycle was 1.0 s and the palmar flexion angle at the catch phase was 35 degrees, the swimming speed became fastest. In the short stroke cycles, the optimized stroke was the motion pulling and pushing the water near the trunk with the elbow bending. In the long stroke cycles, the optimized stroke was the motion pushing the water towards the outside of the body. These strokes were thought to reduce the moment which raises the body, by pushing the water shallowly.