本研究欲探討感測元件數量如何改變預測垂直地面反作用力 (vGRF) 曲線及足底壓力中心 (CoP) 座標之準確度。實驗招募10名健康參與者進行舒適走路及跑步，記錄步態著地期間，測力板之vGRF和Pedar-X system之原始壓力值。以皮爾森相關係數 (PCC) 及方均根誤差 (RMSE) 比較分別由3、5、7、9、11、13、15、17個感測元件組成的八種配置，與黃金標準所測得之vGRF曲線和CoP座標的關係變化。結果顯示不論何種軸向或動作型態，各數量配置與黃金標準之vGRF曲線相關係數及 CoP方均根誤差隨感測元件數量增加而升高與降低，超過11個之後，再增添感測元件已無法明顯提升預測步態動力學參數的能力。本結果在科技應用上可供足底壓力偵測產品的功能性開發使用，開發者可以依據準確度需求選取感測元件；學術上則填補文獻中在感測元件數量選擇未有共識的缺口。

The purpose of this study was to define the effect of the pressure sensor amount on accuracy of predicting vertical ground reaction force (vGRF) and center of pressure (CoP) during gait. Ten healthy participants walked and ran at self-selected speed. Pressure values of all sensor of Pedar-X system and vGRF measured by the force plate during stance phase were recorded. Eight sensor layouts were established and vGRF curves and CoP trajectories between each layout, Pedar-X system and the force plate were compared using Pearson’s correlation coef-ficient (PCC) and root mean square error (RMSE) respectively. The results showed that PCC grew with the amount of sensor and RMSE decreased as sensor increased, and 11 sensors was the stop point. 13, 15 and 17 sensors were no longer able to improve the ability in predicting gait kinetic parameters. This finding can be used for application of plantar pressure detection, developers can select the sensor amount according to required accuracy; as for academic, it fills in the lack of agreement in sensor amount selecting in pervious literature.

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