武術發勁動作之電腦模擬最佳化分析

Abstract

本研究採用電腦模擬最佳化分析法，對武術發勁動作進行分析，探討在經過最佳化計算後所產生的人體發勁動作的變化。研究以三維動作分析系統進行實驗，收集一位武術教練定步雙按發勁動作的運動學資料。再以AnyBody Modeling System建構簡易之二維人體肢段模型，匯入實驗所得運動學資料驅動模型後，給定腕關節水平加速度總和最大作為目標函數，同時限制肌力活化總和最大值小於100%的最大肌力為邊界條件，進行最佳化計算，探討該名研究對象在最佳化後之發勁動作所產生的關節動作改變。研究發現，經過最佳化計算後，腕關節的水平速度與加速度在峰值都增加，模型在動作前期呈現身體前移的動作，腕關節在短暫停頓之後，動作後期出現下肢蹬伸與上身放長的動作，使腕關節再前移，主動施力矩總和的最大值增加。同時，最佳化之後也提升了關節動作的協調程度。AnyBody軟體能經過最佳化計算產生數學上的最佳動作，然而此動作的可行性還需要受試者的實際驗證，此外，本研究僅從二維模型進行探討，若可以三維模型執行此一動作最佳化的預測，預期將有更佳之結果。The study implemented the optimization of the “Fa-Jin” technique in martial art by computer simulation and discussed the change of human movement after optimizing. The kinematic data of one martial art coach in “Fa-Jin” movement were collected by a 3D dimensional motion analysis system. The study built a 2D simple human model by AnyBody Modeling System and drove the model by importing the kinematic data from the experiment. The optimized calculation was carried out by setting the objective function which was the maximal summation of forward acceleration of the wrist and setting the boundary condition which the summation of muscle activities was smaller than 100% of the force. The movement changes of the model were discussed. The results showed that the peak values of both forward velocity and acceleration of the wrist improved after optimizing. In the first half phase, the body segment of model moved forward and then made a very small pause in the wrist. In the second half phase, all segments extended to move the wrist forward again. Moreover, the maximum of the summation of torques in joints increased. The coordination of joints was also improved. AnyBody software predicted the optimal movement by mathematic methods, however, the reality of the optimal movement still needed to be verified in real experiment. Furthermore, the better result was expected by the establishment of 3D full-body model.