Tangent vector-based Archimedes spiral real-time interpolation method and equipment in numerical control system

The invention discloses an Archimedes spiral real-time interpolation method and equipment based on tangent vectors in a numerical control system, and relates to a real-time interpolation method and equipment in the numerical control system. In order to solve the problem that a chord length fitting mode is directly adopted for real-time interpolation of the Archimedes spiral at present, so that a large chord height error exists in a result, and then a large error exists for the Archimedes spiral, and the machining precision is reduced, the invention provides a real-time interpolation method for the Archimedes spiral. According to the method, the longest pulse axis is divided according to the Archimedes spiral section needing to be interpolated, the Archimedes spiral section needing to be interpolated is subjected to interpolation region division, then pulse remainders in the x direction and the y direction are compared, the absolute value of the pulse remainder of which axis is larger than 0.5 is judged, pulse