论文利用法曲率、测地曲率的概念，结合空间曲线的投影柱面、投影曲线的性质，对测地曲率的几何意义给出了一个较详细的证明。
This work gives a detailed proof for the geometric meaning of geodesic curvature by using the definitions of normal curvature and geodesic curvature, and combining the characters of projective cylinder and projective cure.
