针对轴承用钢球表面缺陷检测的生产需求，以实现球面全展开为目标，提出球面螺旋线运动展开原理。首先，设计实现钢球全表面展开的倾斜轴锥面驱动体，并建立其锥面模型;分析展开过程中球面上一点的运动参数，建立钢球和驱动体的接触约束模型，采用迭代法求解拟合出驱动体锥面上接触点的运动轨迹模型;为保证钢球全表面展开，进一步分析球面上接触轨迹，利用弧长积分得到展开过程中球面上的接触轨迹曲线模型;最后通过仿真技术和物理样机试验对钢球展开过程进行分析测试，验证了理论分析结果的正确性。提出的球面展开理论及方法可以应用到高精密轴承球类滚动体的表面缺陷检测设备，也可对其他球类物体的检测提供理论参考。

According to the production requirements of surface defects detection of the steel ball used in bearings,the unfolding principle of spherical spiral line motion is proposed,aiming at unfolding the whole sphere surface. Firstly,the conical driving body with inclined shaft cone is designed which can make the whole surface unfolding of steel ball possible. Meanwhile the cone model is built. Secondly,the motion parameters of one point on the steel ball in the process of unfolding are analyzed,the contact constraint model between the steel ball and the driving body is established,and the motion trajectory model of the contact point on the driving cone is fitted and solved out by iterative method. Thirdly,in order to ensure the full unfolding of whole steel ball surface,the contact trajectory model is further analyzed,and by using arc integral,the contact trajectory curve model is obtained. Finally,through the simulation technology and the experiment of physical prototype,the unfolding process of steel ball is analyzed and tested,which verifies the validity of the theoretical analysis results. The principle and method of sphere surface unfolding can be applied to the surface defects detection equipment of rolling balls used in high precision bearings and can also provide theoretical reference for the detection of other spherical objects.