Mathematical model establishment of the rotating laser vertical error using spherical triangles method

The article analyzes the composition of the Rotating Laser vertical error based on the vertical plane working principle of the rotating laser and build a three-dimensional coordinate system based on a vertical plane established by optical axes of two collimators which is symmetrically distributed in ±β° relative to horizontal axis. Using the sine and cosine theorems of spherical triangles, the formula of the inclination error of the vertical level plane of the rotating laser is deduced. Using the formation characteristics of cone-angle error, the formula of cone-angle error of horizontal level plane is used as of vertical rotating plane. Finally, we build a mathematical model of the vertical error