For the Construction of surface: development of two intersecting cones connected by a plane curve with an automatic plotter, the position of the connected, plane of the two cones should first be exactly calculated. 用自动绘图机绘制接口为平面曲线的两圆锥表面展开图,先要准确计算接口平面的位置,再按接口展开的曲线方程,编制两圆锥相交后的表面展开的绘图程序。