V带与轮槽接触面间周向摩擦力与拉力不共线，导致V带实际运动轨迹并非理论圆弧。为描绘V带真实运动轨迹，实验设计了3种测量方法，讨论了各方法的精确性、操作性，并利用距离传感器法测定了不同转速条件下V带的真实运动轨迹，为准确计算V带当量摩擦系数影响角γ以及当量摩擦系数μ-V提供了有效途径。

The real trajectory of V belt is not a theoretic arc due to deviation of circumferential friction from tension of the belt. Three techniques for measuring the belt trajectory during V-belt drive course were proposed; also the accuracy and the operability were analyzed. The range sensor was applied to measure the real trajectory of different speed V belt. The purpose was to provide effective approaches for acquire the real trajectory of V belt, and furthermore, the accurate calculation of the slope angle γ and equivalent coefficient of friction μ-V.